Entry level 3D printers
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1. Entry level 3D printers Usage and Benchmarking HAMK UNIVERSITY OF APPLIED SCIENCES Bachelor s thesis Kone ja tuotantotekniikka Mechanical Engineering Riihim ki 2014 Petri Heino ABSTRACT HAMK UNIVERSITY OF APPLIED SCIENCES HAMK Riihim ki Kone ja tuotantotekniikka Mechanical Engineering Author Petri Heino Year 2014 Subject of Bachelor s thesis Entry level 3D Printers ABSTRACT Keywords Pages This thesis was made as a primer for getting more involved and special ized in 3D printing The subject was proposed and the opportunity was provided by Aalto University s Digital Design Laboratory ADD located in the Otaniemi campus in Espoo city in Finland Ten different printers implementing four different 3D printing methods are introduced with the machine prices ranging from 2000 to 35000 The writing is based on two months of intensive use and testing The aim was to benchmark the printers and learn how to use them A lot of new knowledge was acguired and the differences between a 2000 printer and a 12000 one became apparent A well established base of knowledge was established for considerations of small series manufacturing with the printers and their correct use and maintenance 3D printers FDM FFF SLA SL Stereolithography Polyjet inkjet 3DP powder printing lamination 61 p f AM K TIIVISTELM H MEEN2. 17 Entry level 3D printers For this thesis three Ultimaker 2s were available for use They proved to be constant in accuracy and reliable if serviced prop erly Common problems in usage were e Nozzles getting blocked when doing filament changes The ABS or other residues block the extruder when print ing PLA because of lower extrusion temperature Improper extruder idler tension resulting in slippages when extruding Problems may appear at the end of the spool e Belts and bolts getting loose requiring periodical atten tion and tightening For belts adding tensioners might be necessary e Filament jams the filament wire getting stuck in the spool holder or tangled in itself Filaments degraded at the end of the spools if old materi al notable with PLA e Difficult nozzle change procedures Disassembling of the complete extruder assembly is required to change the nozzle Besides these obvious problems faced with this kind of machine the Ultimaker has proved to be able to produce good quality parts if serviced right and the used material was good as well Some filaments are much easier to print than others The Ulti makers would print without problems for tens of hours in a row 18 N level 3D printers The Ultimaker has it s positive sides and it s negative sides Printing simple geometries rather slowly would produce very satisfactory results reliably Correct prep
3. http mcortechnologies com 3d printers matrix 300 plus Stratasys uPrint SE n d uPrint SE Plus product page Accessed 9 10 2014 http www stratasys com 3d printers idea series uprint se plus Open3DP Blog 201la Salty parts blog post Accessed 9 10 2014 http open3dp me washington edu 2011 03 salty parts 3dp in salt AIPWorks Objet n d Objet Materials in Finnish Accessed 22 10 2014 http www aipworks fi objet materiaalit Open3DP Blog 2011b Salt printing Research report Accessed 9 10 2014 http open3dp me washington edu wp content uploads 2011 03 Salt Printing pdf 3D Systems press release 2012 Accessed 9 10 2014 http www 3dsystems com press releases 3d systems completes acguisition z corp and vidar ZPrinter 250 User Manual n d Available for online viewing as a Scribd upload Accessed 9 10 2014 https www scribd com doc 233066646 Z Printer 150 and 250 User Manual RepRap Wiki Powder Printer Recipes n d Accessed 10 10 2014 http reprap org wiki Powder Printer Recipes 3D Touch Ultrasonic support removal tank n d User guide and safety manual Available as a PDF file Accessed 10 10 2014 http cubify com en Products DDDTouch Objet 30 Manual n d Available as a PDF file Accessed 10 10 2014 http www ece ubc ca leos pdf tools objet manual pdf Aula J Oiongge T Koskinen H Isomaa T Kinnunen A Kon 41 4005 Loppuraportti 2014 21 3D tulostetun muovin materiaaliomi
4. 3D printers 5 CONCLUSIONS To start with there were 10 different 3D printers to experiment with 6 of them extrusion based 1 SL printer 3 inkjets and a sheet laminating one In reflection I spent most of my time experimenting with the 5 sub 10000 extrusion based printers spending countless hours wanting to get something done on them that they would not pro duce with default settings Besides the setbacks and unsatisfactory results with the cuboid tests 1 would conclude that these kinds of printers can still be really capable printers with experiences relating to using and building RepRap printers It is only a guestion of what is de manded of them and how well you know your machine and ma terials Possibly the Ultimaker could produce similar guality to the uPrint with the cuboids but it may reguire more experiment ing and possibly modifications to the printer Also in the sub 10000 range was the Form 1 The test results were really disappointing because the printer was perceived as a high precision printer What was learned is that the more expensive printers are really worth consideration but also have their problems Materials are expensive and modifications and repairs made by users are lim ited Time usage is a big factor here with industrial machines you spend less time on the machine but pay more whereas on the cheaper printers you spend more time but pay sufficiently less Finally by buil
5. AMMATTIKORKEAKOULU HAMK Riihim ki Kone ja tuotantotekniikka Mechanical Engineering Tekij Ty n nimi Petri Heino Vuosi 2014 Entry level 3D Printers TIIVISTELM Avainsanat Sivut T m p tt ty on tehty alustaksi erikoistumiselle 3D tulostimiin ja men etelmiin Aalto yliopiston Digital Design Laboratory ADD ehdotti ty n aihetta sek tarjosi tilaisuuden ja mahdollisuuden tehd ty t Digital Design Laboratory sijaitsee Otaniemen kampuksella Espoossa 10 erilaista tulostinta jotka k ytt v t 4 erilaista 3D tulostus menetelm esitell n Laitteiden hinnat ovat v lill 2000 35000 Kirjoitus perustuu kahden kuukauden intensiiviseen k ytt kokemukseen ja testaamiseen Tavoitteena oli benchmarkata tulostimet ja oppia k ytt m n niit Ty ss kertyi paljon uutta tietoa ja erot 2000 ja 35000 laitteen v lill tulivat varsin selviksi Ty ss kehittyi hyv tietopohja ja valmiuksia piensarjatuotantoa varten tu lostimia k ytt en Lis ksi tulostimien oikea k ytt ja huoltaminen nou sivat selke sti esiin ty t tehdess 3D tulostus Stereolithografia laminointi pulveritulostus pikavalmistus 6ls CONTENTS 1 ANTRO CON s sea do 1 1 1 an AAS maas cade esa TEN TS SEIN dd acon gg aan eae TN hawk maan utes 2 1 2 Terminology and technology maa lis 3 1 21 EXtUSIOn Das dla 4 1 2 2 Photopolymernzation Dis nina 5 1 2 3 Toei Ase ee sacs a dl
6. In the Form 1 printer as an example the build plat form is lowered into the resin The bottom of the tank is silicon coated plastic and a laser beam moved through mirrors inside the machine is directed through the bottom of the tank A scanning mask could be used instead of a scanning beam as in some visible light curing SL printers where a common house hold DLP projector could be used the LCD screen blocking light the dark places Entry level 3D printers 1 233 Inkjetting based The MJM Multi jet Modeling an inkjet printing method trade mark by 3D Systems and the PolyJet inkjet 3D printing meth od trademark by Stratasys brand names are both photopolymer izing as well as inkjetting based methods The polymer resin is jetted pushed by piezo actuators through small nozzles on to the build area There may be multiple sets of nozzles in rows of many as over 100 in the Objet printers for the ability to deposit different materials The resin may be heated up to reduce viscosity make it flow more easily A very thin layer of material is deposited with the inkjets and then a UV light is moved over the resin to cure it The next layer is printed directly on top of the last one 3DP is a method that implement powder and binder material to build parts Note that the term may also relate generally to any 3D printing method Gibson et al 2010 195 200 See also Wikipedia 3DP n d The Zcorp mach
7. Re 3D Gigabot 2000 2012 Extrusion Stratasys UPrint Plus 15 000 2010 SL FormLabs Form 1 3300 2013 Inkjet 3D Systems Thermojet 50 000 in Some MJM the 1990s time in 1990s Inkjet Stratasys Objet 30 Scholar 35 000 2012 PolyJet Inkjet Zcorp Zprint 250 currently 10 000 2010 3DP currently Projet 260 by 3D owned by 3D Systems Systems SDL Mcor Matrix 300 11 000 2010 Technologies Table 3 Materials processing equipment Machine manufacturer Machine Model Cost Year made estimate Stratasys WaveWash 2000 2012 estimate Stratasys WaterJet 2500 2012 estimate 16 Entry level 3D printers 3 1 Extrusion based printers The most common printers nowadays are the cheap desktop FFF or FDM called differently depending on the trademark and p printers with prices ranging from 500 to 2000 There are many companies manufacturing these printers and several different models were available for the thesis Luckily also a more experi enced one the uPrint SE was also available and this provides a good comparison point for the cheaper ones 3 1 1 Ultimaker 2 Figure 8 The Ultimaker 2 3D printer The Ultimaker is a commercial spinoff from the RepRap project that has been getting popular throughout the world It s based on the company s improved open source software and hardware and all the files and plans at least for the older machines can be found online
8. a de O 6 1 2 4 Sheet lamination processes ii ias iria 7 2 MATERIALS eos STARS 8 Dele Wire filament materials ici 8 2 1 1 Build platforms for filament materials ssossss neen 14 22 Powder matenalsmmasst tae E a v NV ssa Ema ao EE 15 2 37 o SSN SN A a N an 15 24 Liquid maten st ta eb ky 15 3 IMHE PRINTER Se o 16 Z1 Extrusionsbased Pride DA a dd 17 SAA MO Li diia 17 A A 21 BAS O Bee 22 Sole UPrint SE PlUS aiae Kaa R STS samma saa tavata osia 24 32 stereolithooraphy Formi Isommassa A AT ER 27 Dep EP a las eds e e e sid aaa Toe al 31 Sel OS A OS 31 332 VISIT O Sts n e E anon Tl had aa o Kaa Tasan haa jina van Tana kansa maana saa mia a 35 3 33 ZPIMEKIS Oman a ova RE NAN uk saas dasa 37 3 4 Sheet Lamination Mcor Matrix 30O ooooocnnnccnocococncoonnnoncconncconocnnn cono conan nccnnnos 39 4 BENCHMARKING THE PRINTER S cono 42 Mile PT K ITKEN E SAN KN haces ia Atsa 43 AAA Ultimaker cios 45 41 20 UPiint SE PS A 51 Adeg A A E E E E 53 4 1 4 Objet 30 Scholar OS 56 3 CONCEUSIONS KK N A Kas sa AN E E Naa 58 Ge SOURCES noina a Taas acc atte E ata Asada 59 Appendix 1 Printer specifications Appendix 2 Test round up Entry level 3D printers 1 INTRODUCTION 3D printing is a manufacturing technique that has also been called additive manufacturing and rapid prototyping It is a method of manufacturing parts by adding material to build up a work piece incrementally converse
9. because of the honeycomb structure making it rigid on the edges However if printing only the perimeters the outlines of objects much more flexible ob jects could be made Figure 7 Ball printed in flexible PLA Entry level 3D printers PVA Polyvinyl Alcohol Water soluble Extruded at 160 C to 170 C Will absorb moisture once opened and may require dry ing before usage Described to be used as a support material and supposedly will work best with PLA because it s extruded at lower temperatures ABS is extruded at 260 C and may cause degradation if prin ted on PVA Bilbycnc PVA Fact Sheet n d Nylon Polyamide Most Nylons are extruded at 240 C to 250 C Nylon will most certainly require removing moisture be fore printing to avoid air or water bubbles Flexible and durable material Printing on blue tape or a wooden surface is recommended by the manufacturer Taulman 3D n d See also Reprap Wiki Poly amide n d HIPS High Intensity Polystyrene The HIPS plastic is soluble in Limonene an organic solvent making it a possible support material for ABS RepRap Wiki HIPS n d 13 Entry level 3D printers 2 1 1 Build platforms for filament materials There are many methods to reach good adhesion to the surfaces but there is still room for improvement and the best ones are usu ally experimentally determined Not all plastics can be printed on the same surface C
10. deg 0 2mm T b 60 Printed without ABS juice deg and the outer cubes ended up brim bending and making a little round if compared to a flat surface 2 10 45 deg 0 1mm T b 45 White filament would deg and distort from heat too much brim and fail easily see figure 27 Black ABS would need machine fine tuning see figure 29 Finished parts need post processing after support removal sanding etc ABS Juice effective if made with suitable ABS See the table 5 for descriptions Figure 34 A tray of 10 cuboids in ABS freshly removed from printer Notice the amount of material oozing after layers suggesting either problems with the printer settings or the used material 50 Entry level 3D printers 4 1 2 UPrint SE Plus Printing with the uPrint was really straightforward and trouble free compared to the Ultimaker The only problem faced was that when the part was oriented as seen in figure 35 the software would generate bad toolpaths and not print it correctly Using auto orientate resulted in successful results as seen in figure 36 The connection points have a strong feel to them No further pro cessing or experimentation was needed Figure 35 Cuboid printed with uPrint SE Plus Figure 36 Uprint test settings and approximations Printer Materi Layer size Print Infill Tempe Other notes model al speed rature Up
11. oven at 400 C seemed feasible This has not yet been tried because there are electronics suspec tedly piezo elements embedded in the nozzle New nozzles cost around 1000 per piece plus service fees After the nozzle change recalibration of the axes has to be made because of minor changes in the nozzle positions One of the reasons adding up to the cause of blockage is clearly the price of materials Flushing the nozzles spends much of the material and doing this has been avoided at all costs 32 Entry level 3D printers Table 4 The Objet 30 Maintenance Schedule Program Objet 30 Manual n d 101 Task For More Information After every print job Clean the print heads See Cleaning the Print Clean the build tray and Heads on page 7 22 the surrounding area Weekly Perform the Pattern test See Pattern Test on page 7 24 Weekly Clean and inspect the See Cleaning and wiper ni a the Wiper on page 7 25 Weekly Restart the Objet30 printer computer and the server computer Monthly Clean the roller waste See Cleaning and ollector Replacing the Roller Waste Collector on page 7 28 Monthly and after Check the alignment of See Aligning the Print replacing print heads the print heads Heads on page 7 31 Every six months Replace the roller waste See Cleaning and collector Replacing the Roller Waste Collector on page 7 28 Every 500 h
12. plates may lead around 5 a Plus ABS 75 C material is to parts getting piece plate visible on printedon detached from machine ABS plate the plate interface then the actual part in ABS plastic on top of that ABS Juice a term coined on the RepRap forums and wiki for a mixture of ABS dissolved in Acetone and applied on glass plate 14 Entry level 3D printers 2 2 Powder materials Many different powder materials can be printed either by fusing or melting them together or by using a binder material The ZPrinter subject in this thesis uses a binder material to form ob jects in a special powder The powder is as suggested by it s Materials Safety Data Sheet mostly water with color additives whereas the powder is a mix ture of plaster and polymers supposedly PVA or other water solvent polymer or glue There have been records of people using alternative materials on their powder binder printers For example salt could be used RepRap Wiki Powder Printer Recipes n d 2 3 Printable waxes Waxes could be printed such as those used in the Thermojet printer The Thermojet uses waxes described as thermoplastics made out of Hydrocarbons Amides and Esters The machine is discontinued but there are newer commercial casting wax print ers on the market 3D Systems 1998 2 4 Liquid materials The stereolithography Form 1 and the inkjet printers Ob
13. to the previous one Forming means that the sheet is cut to the desired shape with a knife a laser beam by milling it or by other methods The bonded sheets may be almost any material ranging from pa per to ceramics to sheet metals Gibson et al 2010 207 210 X Y plotter Layer outline and cross hatch Laser Heated Roller Polymer Coated Excess Paper Material Material Supply Roll Figure 4 Schematic of one of the first commercialized lamination processes the Layer Object Manufacturing LOM process Gibson et al 2010 208 Entry level 3D printers 2 MATERIALS The used materials depend on the printing process as seen in the previous chapter Notable about the materials is that the price can vary a lot The used photopolymerizing resins have been getting considerably cheaper as the user base is getting wider and with more printer manufacturers entering the market This can also be seen on the wire filaments The industrial grade materials can be very close in chemistry to the ones used in the cheaper printers However the price difference can still be ten times It is also good to remember that neither of the two stand up to comparison if compared to the price of thermoplastics used in the injection molding industry where the material cost can be much lower in the range of only a few Euros 2 1 Wire filament materials The industrial grade spools come in sealed packag
14. transition temperatures for ABS are high er For example MatWeb has over 2400 different grades of ABS lis ted on their website There is no single universal form of ABS that you can get but it s properties are somewhat manufacturer and grade dependent MatWeb ABS n d PLA Polyactic Acid Biopolymer Extruded at 170 C to 220 C however some grades may need a higher temperature of 245 C to flow properly Notable properties of PLA are as fol lows easier to print than ABS because of less warping due to lower extrusion temperature and it is less demanding on the build platform Biodegradable material Harder surface than ABS Ex truder usually need less force on the idler pulley because of the hardness of the plastic to avoid digging in to the filament Mat Web PLA n d may degrade quite fast depending on the grade if the spool is opened from packaging and left unattended The materi al becomes very hard and fragile and impossible to print may be used as support material for ABS The supports can be removed by immersing the part in hot water for 48 hours or by using an ultrasonic washing tank with a solution of caustic soda for 3 hours 3D Touch Ultrasonic support removal tank n d 10 N level 3D printers Wood filament These filaments are mixtures of some ground wood material and PLA or some other plastic Extruder block ages may be experienced with smaller nozzle sizes Spools of wood filamen
15. was plastic The reasons for the skipping were investigated Firstly a too low belt tension was suspected but apparently the stepper motor drivers currents were not adjusted by the manufacturer This may have resulted in the motors skipping steps losing positional accuracy The motors would skip steps if loaded by hand when the printer was on While investigating the printer for faults it was clear that the stepper motor driver boards current trim pots had not been ad justed properly They were all in the same orientation in the middle of adjustment range 25 Entry level 3D printers 3 1 4 UPrint SE Plus Figure 3 uPrint SE Plus 3D Printer The uPrint SE Plus is an entry level industrial FDM printer It has an air circulation system to heat up the enclosed build plat form disposable build plates and a purging and nozzle wipe sys tem to keep the nozzles clean the nozzle is wiped against a met al brush periodically Entry level 3D printers Compared to Ultimaker for example the uPrint has more elec tronics and sensors in use which detect for example material misfeeds and failures This compared with the rigidity and it s custom made parts make it a guite different kind of a printer than the Ultimaker The printed supports make this printer a lot more versatile than the other FDM machines in this thesis It is possible to print al most any shapes with enough supports but this may be
16. 4 hours Manuals recommend that it would never be shut down It soon became apparent that servicing the machine is important The blade may get stuck if the assembly is dirty The glue deliv ery line might works badly if the deposition roller has any re mains of adhered glue on it 39 Entry level 3D printers Figure 25 Test piece tried with Mcor Several trials were made to try to print the thin object in Figure 25 with Imm features that were especially challenging to the Mcor Printing the object with the extrusion based machines or with the Form 1 printer presented practically no problems with it the Mcor was constantly failing Figure 26 Paper layers getting detached during printing 40 N level 3D printers After proper maintenance of the glue deposition head and the blade these similar problems were still present but lesser Prin touts have very different properties to the other printers The lay ers are easily detachable and the parts are fragile but can hold up to compressive forces Figure 27 A small gear of approximately 10mm in diameter printed with the Mcor showing easily separable layers However after the minor improvement in print quality after all around cleaning and maintenance every part tried on the printer would fail even the semi complex If paper objects are a must the printer should be investigated more but with the obtained results the printer se
17. 74 cm wide x 79 cm deep x 140 cm high Machine weight 166 kg Resolution 0 102mm minimum feature size 0 41mm Connection by Ethernet Mcor Matrix 300 Mcor technologies n d Build material standard A4 Paper Build Size A4 Paper 256 x 169 x 150 mm Resolution theoretically 0 1mm paper thickness Machine dimensions 950 x 700 x 800mm Machine weight 150kg Connection by Ethernet Title of thesis Appendix 2 Test round up Table 13 Cuboid test round up and weighted points 1 to 4 4 for best for test results Printer Accuracy Cost 10 ing costs Print Operation time Set up Suitability for mass time 10 10cuboids maintenance production of 10 pieces cuboids estimate time by points estimate build materials only
18. C Support material extruder 300 C and build chamber 75C Formlabs Form 1 Speed fast in x y Layer thickness 0 025mm 0 050mm or 0 100mm Build volume 125 x 125 x 165 mm Files transferred via USB connection to from a PC e Preform software has very good user interface but lacks machine settings such as laser beam power and speed settings that you might be interested in if you use custom resins Objet 30 Scholar Stratasys Objet 30 data sheet n d Speed fast in x y Build Resolution from Objet30 Pro datasheet X axis 600 dpi Y axis 600 dpi Z axis 900 dpi Size 82 5 x 62 x 59 cm Weight 93 kg Build Size 294 x 192 x 148 6 mm Layer Thickness Horizontal build layers down to 0 016mm Connection by Ethernet includes embedded computer Seen on the printer software the print area is kept at ambient tem perature of 31 C and the print heads are kept at around 73 C to 76 C during printing Title of thesis 3D Systems ThermoJet 3D Systems 2001 Build materials ThermoJet 2000 and ThermoJet 88 Thermo plastic Wax build material Resolution 300 x 400 x 600 DPI xyz Maximum model size 250 x 190 x 200 mm Machine dimensions W1 37 x D0 76 x Hl 12 m Machine weight 375kg Connection by Ethernet Zcorp ZPrinter 250 ZPrinter 250 User Manual n d 2 3 Build speed 2 4 layers per minute Build material zp 150 Powder with zb 63 Binder Build Size 185 x 236 x 132 mm Machine dimensions
19. S TJ88 Finnish pdf 3D Systems 2005 Material Safety Data Sheet in English Accessed 6 10 2014 http www 3dsystems com products datafiles thermojet msds 22647 S12 00 SDS TJ88 EU pdf 3D Systems 2001 Thermojet Datasheet Accessed 6 10 2014 http www 3dsystems com products datafiles thermojet datasheets TJ Pr DesignComm pdf GE Press Release 2014 GE Aviation Selects Auburn AL for High Volume Additive Manufacturing Facility Accessed 6 10 2014 http www geaviation com press other other 20140715 html Materialise Technologies amp Materials Overview n d Accessed 6 10 2014 http manufacturing materialise com all available materials Wikipedia 3DP n d Accessed 6 10 2014 http en wikipedia org wiki Powder bed and inkjet head 3D print ing 59 Entry level 3D printers Stratasys Objet 30 data sheet n d Accessed 6 10 2014 http www stratasys com media Main Secure System Spec Sheets SS PolyJet objet30 20pro 20brochure letter 20stratasys 20low 20res pdf MatWeb ABS n d ABS Property data page Accessed 6 10 2014 http www matweb com reference abspolymer aspx MatWeb PLA n d PLA Material overview Accessed 6 10 2014 http www matweb com search DataSheet aspx MatGUID ab96a4c0655c4018a8785ac4031b9278 Ultimaker n d Ultimaker 2 specifications Accessed 8 10 2014 https www ultimaker com products ultimaker 2 Taulman 3D n d 618 Material specification
20. The Objet printers work by depositing a very thin layer of resin on top of a previous layer and curing it with UV light Layers are deposited next to each other to build up parts There are two different nozzles each one with over 100 small holes in a row for jetting the resin The other nozzle is for the build material and the other for printing support materials 31 Entry level 3D printers The Scholar is a 3D printer marketed specially for educational use but it is almost identical to the Objet 24 and Objet 30 Pro versions The difference between different Objet machines is mostly in the availability of the materials The resolutions are the same but the build area varies a little and the layer thickness is thinner in more expensive machines Objet24 Objet30 Objet30 Pro Objet30 Scholar VeroWhitePlus RGD835 x X X X VeroGray RGD850 VeroBlackPlus RGD875 VeroBlue RGD840 DurusWhite RGD430 Endur RGD450 VeroClear RGD810 High Temperature RGD525 X X X x X x x x X X xXx x x x Rigid opague Scholar RGD240 X VeroDentPlus MED690 Objet MED610 Figure 20 Objet 30 materials availability AIPWorks Objet n d The machine for use had been standing for over a month without usage during the summer holidays This had caused the nozzles to get blocked most probably because of plastic polymerizing inside the nozzle rendering them useless Methods to open the nozzles were researched and burning them open in an
21. al jam with the spool getting tangled and while servicing the heater wire got broken because of too much bending A new one would cost around 35 Figure 10 The Ultimaker nozzle assembly showing the hot end and cold end with the cooler fan Not showing the heater and temperature resistor in the brass block below 20 Enti level 3D printers 3 1 2 3D Touch IEI SS Figure 11 The 3D Touch printer The 3D Touch is a discontinued but still a rather popular printer in Finnish schools It has it s own software tool path which is quite easy to use but it doesn t have many features for customiz ation The prints are very slow and the reasons are apparent The print er is set to periodically ooze and clean the nozzle by purging it to a special container by wiping it against a plastic plate The corner guard ball mentioned in chapter 2 1 took over 50 hours to print with the 3D Touch compared to the Ultimaker 2 which took 13 hours on it The build area is a sheet of laminated plywood It can be challen ging to find the best methods for proper adhesion to this surface Printing ABS is practically impossible because of parts getting detached and warping Entry level 3D printers 3 1 3 Gigabot Figure 12 The Gigabot printer Notice the missing extruder The printer had suffered from extruder meltdown and molten plastic is visible on the build platform The Gigabot was delivered as assembled from USA It
22. al produc tion methods with complicated designs especially in the aerospace industry Recently in the 2014 General Electronics Aviation division established a 50 Million Dollar additive manu facturing facility in USA GE Press Release 2014 There is a wide range of different additive manufacturing tech nologies besides the ones mentioned in this thesis but research ing all of them is out of the scope of this thesis and the technolo gies will be reviewed only briefly Interesting methods would be for example direct write methods including plasma ionization or deposition of powder metal through a nozzle that melts it at the same time with a laser beam The reader is suggested to research them online or to acquire for example the book Additive Manu facturing Technologies 2010 Gibson I Rosen D Stucker B E ISBN 978 1 4419 1120 9 Entry level 3D printers 1 2 Terminology and technology Several different abbreviations are commonly used in 3D printer technology some of which are reviewed here along with descrip tions of the technology Gibson et al 2010 See also Materialise n d As a general description initially the part being manufactured is modelled in a CAD program a 3D model is made and then this file is processed so that information for creating the part is made for the printer 3D models are universally somewhat standardized transferred to the 3D printer software in a stl forma
23. arations would be necessary if printing in ABS the build plate would have to be prepared with ABS juice to avoid warping Even with the ABS juice some very large parts could still warp too much and become bent Figure 9 Milling machine parts printed in ABS with the Ultimaker The biggest piece was bent about 3 mm from the middle after removal Heated bed at 100 C with ABS juice Entry level 3D printers The printer has only one nozzle but the Cura software is able to produce supports for the printed parts built with the same materi al as the actual part Printing with supports works but with too fine details removal becomes very work intensive and not worthwhile if done manu ally with sidecutters a knife and a file Usually every problem encountered with the prints came up with some change to the machine If there was a change of spool the new spool could get tangled If the material type was changed problems with the nozzle were encountered Therefore the Ulti maker might be best suitable for single purpose use and not as a 3D printing testbench Printing wood filament was tested on an Ultimaker The prints constantly got blocked with the original 0 4mm nozzle As a solution to this the nozzle had to be changed to a bigger one A decision was made to drill the nozzle to a bigger size This was done on a Bridgeport mill with a 0 6mm HSS drill After one month of use this same printer would suffer from materi
24. asured 16 to 16 1mm Connection points 1 1 weak on both to 1 9mm strongest with nozzle 0 6mm between parallel ones 3 4 Default 0 06mm T b 60 deg and Connection point between brim overhung cube much stronger than with 0 2mm layers The printed pieces measured 15 9mm each Connections 1 1mm on overhang and 1 4mm elsewhere 4 14 45 0 06mm T b 45 deg and Best quality PLA prints degrees brim reached measuring 16mm by sides and 1 3 to 1 5mm on connections Note that every print used 1 2mm for shell and bottom top thicknesses fill density 20 and 50mm s for speed except 40mm s for the last tests with very low layer size Lines setting was used for generating supports 2 The 60 degree support setting would generate support only for the flat sur face between the two cubes on the sides whereas 45 degree generates in also on the sides of the cubes See figure 25 Brim means printing a flat surface of one layer extending over the part to reach better surface adhesion 49 Entry level 3D printers Table 7 ABS test prints results on Ultimaker 2 Build platform was treated with ABS Acetone mixture and heated to 100 C Extruder temperature was 260 C for each test Each test was printed with both two printers one with white ABS and one with black Test Pieces Cube Layer Support Results at orien size s structures once tation 1 13 45
25. ding your own printer and spending time to learn how everything works you end up using less time to do maintenance or changes The selection of a suitable printer seems like a real personal and case dependent task All in all none of the printers that were reviewed gave com pletely satisfactory results As for my own persona opinion and view on continuing this work constructing my own printer seems like the best option cost and time wise either with a heav ily modified RepRap Ultimaker or similar extrusion based print er For anyone s particular solution time money and guality are the biggest guestions See attachment 2 for round up of the tests 58 Entry level 3D printers 6 SOURCES Additive Manufacturing Technologies 2010 Gibson I Rosen D Stucker B E ISBN 978 1 4419 1120 9 E book accessed through school network also available as a paper version GNU GPL 2007 General Public License Accessed 6 10 2014 http www gnu org copyleft gpl html GPL Violations Vendor FAQ Accessed 6 10 2014 http gpl violations org fag vendor fag html Creative Commons Case Study n d Technical Case Study Accessed 6 10 2014 https wiki creativecommons org Special SearchByProperty title Special SearchByProperty amp property Tag amp value technical de tails 3D Systems 1998 Material Safety Data Sheet in Finnish Accessed 6 10 2014 http www 3dsystems com products datafiles thermojet msds MSD
26. ems very limited in it s capabilities and very expensive to use overall The machine is slowly consuming it s glue and blade when not in use and both are expensive raising questions about the future of this printer Entry level 3D printers 4 BENCHMARKING THE PRINTERS A test piece was used to contest the printers The piece consisted of three cubes connected together in different planes The cubes measured 16 x 16 x 16 mm each The faces of the cubes were along the same planes The diagonal of the squares connecting the cubes was 2mm and the fillets were 1mm The cuboid was designed in Open Source CAD program called FreeCad version 0 14 and exported in stl file format Figure 28 The cuboid visualized in FreeCad It may be difficult to have an universal test piece for all the dif ferent printers For example the SL and inkjet printers are able to print very small features under Imm accurately whereas FDM printers may struggle greatly Different printers have their strengths and weaknesses Zprint Thermojet were both non operational during the time of tests Mcor was producing too inconsistent results and gave the impression of a very unreliable machine None of these three could suggestively produce strong enough parts for purposeful handling of the pieces straight out of the printer Therefore Zprint Mcor and Thermojet were left out of the tests These printers are most suitable for the specific parts designed for printin
27. es and include moisture absorbent material The materials used in the uPrint machines are called ABS Plus with different brand names that are extruded at 300 C according to the machine interface The special spool holder type that they use plus the included circuit board in the spools makes the use of custom filaments im possible or at least very difficult The uPrint has fixed settings for extrusion temperatures For lower price range printers there is a huge variety of different materials available Currently there is no standard for the spool sizes and this causes problems with interchangeability between the machines The spool format is manufacturer dependent N level 3D printers The specific chemistry and properties of each plastic type can differ greatly depending on the grade and the additives such as plasticizers colorants fillers etc Very different properties have been experienced depending on the filament color for example Figure 5 Filament spool fitted on the back of Ultimaker 2 Entry level 3D printers ABS copolymer of Acrylonitrile Butadiene and Styrene Extruded usually at temperatures ranging from 220 C to 260 C The uPrint machines use a grade of ABS that is extruded at 300 C ABS is subject to even violent heat shrinkages and warp ing during printing and therefore it is very demanding on the build platform Printed parts can tolerate higher temperatures than PLA as the glass
28. g with them The Ultimaker 2 stands out positively among the 2000 price range printers The other printers were not actively used for mechanical weaknesses or problems or just because setting them up would be time consuming and would require a great amount of tinkering with to get them printing Objet Ultimaker uPrint and Form 1 were selected for final tests These were all in operation most of the time during the making of this thesis and proved to be the best printers in house Entry level 3D printers 4 1 Test prints During the preliminary tests on the printers it became apparent that the cuboid should be printed in a 45 degree tilted position towards the build plate This made the layer wise properties of the print much better in the thin connection points When the connecting ribs were printed parallel to the machine s build area s plane they became noticeably weaker against bend ing in this direction because of layer properties Also it is obvi ous that this connection point is the weakest link and very low infill should not affect the overall material strength noticeably The same behaviour has been observed in tensile tests performed on 3D printed pieces strength of ABS test pieces printed in ho rizontal orientation could reach up to 80 of the tensile strength of injection moulded pieces whereas parts printed in vertical ori entation might reach only 25 of the strength before plastic de formatio
29. gs and approximations Printer Material Layer Print Infill Temperature Other notes model size speed Ultima PLA 0 06 to 40 and 20 Nozzle Several ker2 and 0 2mm 50 210 C or methods ABS mm s 260 C tried 3mm Bed 75 C or spools 100 C Print time generated by software Material cost 30min to 1h 30min per piece depending 30 kg overall 1 15 meters per on the settings cube 9 grams Cura estimate so 1h 30min with layer size 0 1mm 1 2mm approximately 0 03 or 3 cents solid layers on shells 20 infill print speed 50mm s and generated supports Figure 30 The cuboid oriented in 45 degrees angle in Cura Entry level 3D printers Notable about the PLA tests is that each one of the prints had some imperfections less so with the slow but finer 0 06mm layer prints Sanding and finishing with a knife or side cutters was ne cessary If printed in default orientation the overhang s lower surface had very poor surface finish with both grid and line type supports N 2 ayitimaker mf sa Figure 31 Cuboids printed at default orientation with grid type supports in PLA With the second series of tests ABS filaments were used The preliminary tests all failed for not being adhered properly due to warping on the build surface when it was treated with plastic coating spray Therefore the ABS juice method was tried which also failed whe
30. had been standing for long times without usage It uses RepetierHost and common open source components similar to the Leapfrog The printer is poorly documented and no manual could be found The settings for PC communication were iterated manually Special about this printer is its promised large build volume of 600 x 600 x 600mm compared to the usual 200 x 200 x 200mm of the other printers However printing big objects will take long times An estimate of 180 hours was given by the software to print an almost full volume object with 0 3mm layers and 35mm s speed with a 0 4mm nozzle Entry level 3D printers The Gigabot had many problems when taken into use Firstly of all prints were suddenly stopping after couple of layers Secondly the y axle would skip 50 mm in a positive direction after 10 or so layers These problems would appear randomly The y axle skipping resulted finally in a situation of apparent fire threat The thermistor from the extruder nozzle got separated from the heater block possibly by getting stuck in the floating filament extruded in to air This caused the heater to turn on maximum for almost 10 minutes which melted the extruder bar rel made of some temperature resistant thermoplastic Luckily the firmware aborted the print automatically after the said 10 minutes Otherwise the situation could have resulted in the plastic catching fire Now the only loss was the melted extru sion cold end that
31. he WaveWash system supplied by Stratasys to remove the supports The washing sys tem works by circulating tap water and an added mixture of So dium Percarbonate and a mixture of Tetrasodium N n bis carboxylatomethyl l glutamate and Citric Acid added before starting the wash cycle Mechanical removal is possible and in simple cases more effective The filament spools are supplied by Stratasys They are de livered in a sealed bags and there is moisture absorbent material inside the package The spools include a small circuit board de scribed as an EEPROM chip This is in effect makes it very dif ficult if not impossible to use second hand materials on the print er The spool prices can be as high as 190 per spool if bought sep arately The price can be slightly lower if the spools are bought in large amounts The build plates cost around 5 per piece These are remarkably higher prices than with the materials used in the Ultimaker machines and the like but of the same type of plastics All in all the uPrint is a reliable machine but it s options are limited and it is very expensive to use when compared to the cheaper ones made by smaller companies The combination of a well maintained heated build platform and high guality plastics makes the print results very consistent and good in mechanical properties 26 Entry level 3D printers 3 2 Stereolithography Form 1 Figure 15 The Form 1 stereolithograp
32. her temperatures may be necessary if printed at higher speed but it is important to remember that plastics can thermally decompose if left at elevated temperature for long times The material may be deposited either in filament form with a pinch wheel extrusion system or with a feed screw in granule form The parts are usually built hollow with an infill pattern Entry level 3D printers 1 2 2 Photopolymerization based In photopolymerization processes a thermoset plastic resin is used thermoset means that the plastic is cross linked and rigid after setting down and can not be thermally reformed as the polymer chains arranged so The resin is delivered in liguid form and deposited differently in each method All of the machines implementing this method subject to this thesis use ultraviolet light UV wavelengths ranging from ap proximately 300 to 400nm to cure the resin Resin also exist that are curable with light in the visible spectrum used in differ ent printers In Stereolithography abbreviated SL or SLA the resin is in a tank and the part is built inside the tank touching the liguid res 1n MEN Gaan Laser a Galvanometers Figure 2 Schematic of Stereolithography Gibson et al 2010 65 The SL system may work opposite to the schematic in Figure 2 reguiring less resin to be available but having disadvantages such as forming adhesive forces between the tank and the build platform
33. hy 3D printer The Form 1 works by lowering a metal plate build platform in the resin and using a 405nm wavelength UV laser that is directed by mirrors to polymerize a layer next to the previous one The polymer tank comes pre coated with a silicone gel to prevent the parts sticking to the tank Tanks are disposable and are recom mended to be used for 1 or 2 liters of printing The Form 1 ver sion is a faster later version than the Form 1 printer from Form labs Formlabs Form1 n d There were two Form 1 s for use for this thesis The other Form 1 in use had a particular problem with printing from the start The parts being printed would adhere too strongly to the resin tank and fail because of that This problem would suffice despite changing the tank the build platform resin and fine tuning the z axis N level 3D printers The other a few months newer would work much better produ cing constantly good prints with the cuboid The difference between the two machines raised many questions as if this would be a machine property why would the same part print successfully on one but not on the other Figure 16 An art piece printed with the Form 1 The printer works best with small surface area pieces and doesn t have problems producing fine details if they are properly supported The pictured piece was broken during support removal requiring gluing Also sanding was needed for surface finish The Form 1 uses a notably use
34. ibility of the printers but still industrial us age is dominant These industrial machines are made by large and professional companies from which the biggest two are Stratasys and 3D Systems For the cheapest printers there are many big and small companies making them around the world The onset of popularization of the extrusion based 3D printers was mostly set by expiration of crucial patents and the very suc cessful open source RepRap project Also freely distributed designs and building instructions play a huge role with services such as Thingiverse www thingiverse com The open source hardware and software on the internet is com monly distributed under either the GNU General Public License GPL or Creative Commons CC licences The CC licences may have limitations to commercial use set by the publisher the GNU GPL licence is a good example of a licence set to try to en sure the work to remain in public domain and not hidden under commercial use only These licences have representatives in many countries and have even been successfully used in court GNU GPL 2007 GPL Violations n d See also Creative Com mons Case Study n d Huge advancements have been made lately in the methods where a laser beam or an electron beam is used for joining powder met al together appropriately so that a work piece is formed such as Selective Laser Sintering SLS or Direct Metal Laser Melting DMLM and are becoming competitors for tradition
35. improvement Connections 1 3mm from 0 1mm layers Suspected air bubbles or cured resin in tank making more imperfections Clear 0 025m Best out of the 16 1 16 3mm Same as above resin m three Connections 1 5mm The properties get better as layer size decreases and part becomes stronger better guality more rigid 54 Entry level 3D printers All of the prints from the Form 1 included some visible imper fections and the reason for those is unknown The resin tank was visibly clean and it had been on low usage Other prints and preliminary tests with the Form 1 suggest that the machine is very accurate in the pure x y axis motions A pre liminary test version was printed with default orientation and it measured from 15 9mm to 16 1mm by the cubes faces Figure 40 Cuboid printed with Form 1 with 0 025mm layers Notice the imperfections inside the cubes and the bottoms where the support structure was built p Entry level 3D printers 4 1 4 Objet 30 Scholar Printing with Objet was easy but expensive When starting to print the cuboid the build material resin bottles had expired by two days and the machine gave error codes for this and reguired material change before printing wasting 1 bottle of unused resin worth 300 The bottles have a RFID tag taped on to them that the printer reads the date from The print was rather tall a
36. ine uses a method of inkjetting a binder material viscous fluid in to a powder The binder adheres adjacent powder particles together A new layer of powder is deposited evenly with a spreader that may be knife like or a roller Unused powder may be recycled and used to print again X Y positioning system jo Inkjet print head Powder spreader Y Part y Binder droplets Unused powder Build platform Figure 3 Schematic of 3DP process Note that with the photopolymer inkjet printers the part is built straight to the build platform and support material is also jetted and there is no powder used anywhere Gibson et al 2010 196 Entry level 3D printers 1 2 4 Sheet lamination processes There are several different kinds of sheet lamination processes with different brand names associated with them For example the Mcor Matrix printer uses a process named Se lective Deposition Lamination SDL where a titanium knife is used to cut a single layer of ordinary A4 paper that has been glued on top of a previously bonded and cut sheet of paper The laminating processes are separated in two ways The first way would be to first bond the laminated sheet and then form it Conversely the sheet can be first formed to the wanted shape and then bonded to the previous layer Bonding means that a sheet is glued thermally adhered or for example ultrasonically bonded called Ultrasonic Consolidation
37. ith automatically generated supports in PreForm software Table 9 Form 1 test settings and approximations Printer Material Layer Print Infill Other notes model size speed Form 1 Clear 0 lm Depends Solid Trials to print with Plus resin m on layer no reduced supports led to 0 05m size option failures with part falling m off from the build and platform 0 025 mm Print time generated by software Material cost 1h 34min with 0 1mm layers actually 125 Liter overall 1h or less on the printer also multiple Volume of one piece 18 5mL with pieces would print at just minor supports increase if printed simultanously Approximate cost 2 3 per piece 53 Entry level 3D printers Figure 39 Picture of the skewness of the cubes printed with 0 1mm layer thickness Part was oriented 45 degrees suggesting either improperly tuned z axis or some other fault Table 10 Form 1 print results Machine Layer Visual Caliber measurements Finishing Material size inspection min max cube operations and notes needed supplier Form 1 0 1mm Squares badly 15 8 16 1mm Washing the Clear skewed up Connections 1 1mm part in resin by connection Isopropyl FormLab ribs very Alcohol to s flexible and remove thin lots of uncured resin imperfections Support and material removal and voids sanding Clear 0 05mm Some 15 9 16 3mm Same as above resin
38. jet use UV curable resins The resulting parts are of thermosetting plastic and very different in properties to the thermoplastics used in the extrusion based printers Little information about the chemistry of the resin can be found mainly from the materials safety datasheets Manufacturers give however technical properties for the plastics such as tensile and impact strengths and glass transition temperatures Traditionally end users were limited to outsourcing the resins from the printer manufacturer Nowadays there may be alternat ive options available for far cheaper prices mainly because of the open source printers becoming more popular Makerjuice Labs n d The Objet printer uses a different support material deposited from a separate printing head during printing The supports are removed by using pressurized water after printing 15 Entry level 3D printers 3 THEPRINTERS The machines that were available for usage for this thesis are listed in tables two and three More in depth analysis of the ma chines and user experience gained from this thesis can be found in the later chapters Table 2 3D Printers Manuf acturer Machine Model Cost Year estimate made Extrusion Leapfrog Creatr Creatr XL 1400 2012 4000 XL Extrusion Ultimaker Ultimaker 2 2000 2012 Extrusion Bits From 3D Touch 2000 2010 Bytes Extrusion
39. ly to removing material from a blank as in machining Making parts this way has several obvi ous advantages such as saving material and reducing the need of patterns for molds Aalto University s Digital Design Laboratory ADD offered a chance for learning how to use their machines and to get to know their capabilities ADD laboratory had 10 different 3D printers available at the time of writing 2014 Besides believing that 3D printers will get much more popular in the future as a manufacturing method motivations for starting this work were to gain knowledge how to coordinate a 3D print ing shop factory would the printers be good for commercial small scale manufacturing and what are the strengths weak nesses and best applications for the printers available Also learning how the different machines were constructed would provide a good chance to learn machine design perspectives Before starting this thesis I had been interested in all kinds of ad ditive manufacturing methods but had only limited experience of using them limited to RepRap building projects and using and improving a Minifactory 2 at my previous workplace There fore getting my hands on machines worth several thousand or tens of thousands of Euros was a unigue and highly interesting opportunity for me Entry level 3D printers 1 1 3D Printing nowadays Fxtrusion based desktop 3D printer are getting widely popular due to increasing vis
40. n Notable about the tensile tests is also that injection moulded ABS might deform before breaking up to 32 while results for horizontal and vertical 3D prints are approximately 7 5 and 2 5 respectively Aula et al Kon 41 4005 Loppuraportti 2014 21 Printing in the 45 degree orientation had its positive and negat ive sides FDM printers could knock the pieces down easily if the piece was not properly adhered to the build platform or warped due to heat distortions After printing the cuboids visual tests to notice distortions and differences and measurements with a Vernier s caliber were made 43 N level 3D printers Figure 29 Bad surface finish as seen on the planes where supports were printed on preliminary tests on the Form 1 This is also the piece that is described as the preliminary test piece in the thesis The surface quality of the parts is dependent on the orientation If there is a support structure printed the surface plane that the part is created on after the supports can have very rough fin ishes due to non uniform material deposition plane The depos ited material doesn t have a flat surface to be start with This makes the later finishing operations necessary With the Form 1 as the part is being peeled off the resin tank there is some adhesive forces that may pull the piece out from the build platform making the generated supports a necessity to keep the 45 degree angle o
41. n done with the Ultimaker Natural ABS filament This would get separated from the glass and form weak points with air bubbles between the film and the glass 47 Entry level 3D printers Figure 32 l ABS prints with Ultimaker Natural ABS getting detached when knocked over by the extruder nozzle due to heat distortions Figure 33 Visual description of the thickness of ABS juice used Acetone is fully evaporated in picture A very runny solution was used prepared with ABS Plus filament used in the uPrint SE Plus Care must be taken not to break the glass by too fast cooling or heat up Entry level 3D printers Table 6 PLA test prints results on Ultimaker 2 Build platform was sprayed with plastic coating spray and heated at 75 C Extruder temperature was 210 C for each test Each test was printed with both two printers one with white PLA and one with black For each machine the toolpaths with correct nozzle diameters were generated using Cura 14 07 Test Pieces Cube Layer Support Results no at orien size s structures once tation 1 1 45 0 1mm Touching With many different degrees 0 25mm buildpla te settings the cube failed T b 60 deg many times and the idea and brim of printing single at once was abandoned 2 13 Default 0 2mm_ T b 60 deg and The parts printed out brim completely but the connecting point for the overhung sguare was unacceptably weak Cubes me
42. n to the piece After printing the parts are washed in Isopropyl Alcohol to re move uncured resin The supports are mechanically removed by the user Formlabs has provided very good documentation for all procedures on their website including advanced tips for parts design applications etc Overall the Form 1 is a good machine for fine details and small pieces However it has it s problems and correct use is a neces sity Keeping everything clean is time consuming but with suit able pieces the Form 1 is a very notable printer The competing stereolithography 3D printers several times more expensive mak ing the Form 1 a considerably choice at around 3500 if it s fea tures are needed It is however not a clear winner over the ex trusion based printers as imagined by the writer before starting to use it 30 Entry level 3D printers 3 3 3 3 1 Inkjet printers The inkjet 3D printers available are characterized as expensive and large in size There are no cheaper printers available cur rently and the two available for the thesis were much more ex pensive ones than the other printers The inkjet 3D printers work guite similar to the 2D inkjet print ers as in material deposition but the materials are of course dif ferent and there is an added z axis and the inkheads also move in y axis instead of moving the paper Objet 30 Scholar a Figure 19 Objet 30 Scholar 3D printer pictured
43. naisuuk sien m ritt minen Aalto University unpublished final report from a Mechanical Engineering course 61 Title of thesis Appendix 1 Printer Specifications in order of presentation Ultimaker 2 Ultimaker n d Speed 10 300 mm s user definable default 50mm s Layer thickness 0 02mm to 0 25 mm user definable nozzle size limits the maximum default 0 1mm Build volume 230 x 225 x 205 mm Files transferred via an SD card Maximum nozzle temperature 2609C Maximum heated bed temperature reached 100 C Build platform type Heated glass plate Used filament any thermoplastic of diameter 2 85 3 mm not able to print 1 75mm filament because of molten plastic reach ing and blocking the cold end of the nozzle tested e Settings are completely customizable in the Cura software by the user making it quite versatile machine for experienced users Oth er softwares could also be used for slicing such as Slic3r Besides this the generated gcode can be customized manually There are many materials available PLA and ABS are the most common ma terials Bits From Bytes 3D Touch Cubify n d Speed maximum 15 mm s Layer thickness 0 125mm Build volume 185 x 275 x 210 mm triple extruder Files transferred via an USB memory stick Maximum nozzle temperature 260 C Build platform type Laminated plywood Used filament any thermoplastic of diameter 2 85 3 mm Re 3D Gigabot S
44. nd that s why it took a long time on the Objet The Objet is fast if parts of the same height are built at once Figure 41 The finished cuboid after support removal printed on Objet Table 11 Objet 30 test settings and approximations Printer Material Layer size Infill Other notes model Objet VeroWhite 900 DPI Full Support material has no 30 default no no options and is generated Scholar options options automatically Print time generated by software Material cost 4h 26min 1041 layers multiple pieces 300 kg overall model material would print at just minor increase in 150 kg overall support material time if printed simultaneously Consumption 27g model 20g support Approximately 11 per piece 56 N level 3D printers Figure 42 The same cuboid before support removal covered in support material The support material is fragile and sticky wax like substance It is difficult to remove with a knife and best done on the WaterJet machine supplied by Stratasys Table 12 Objet 30 Scholar print results Machine Visual Caliber measurements Finishing Material inspection min max cube operations needed and notes supplier Objet 30 Very 16 1 16 2mm Connections Washing the Scholar constant 1 6mm support material VeroWhite milk like off by texture with Stratasys some surface roughness Entry level
45. ommon problems are first layer not ad hering at all to the platform parts getting detached from the plat form during printing parts warping under heat Printing PLA on a clean surface of glass or aluminium might be possible after proper cleaning with dissolvant leaving no residues such as Isopropyl Alcohol RepRap Forums n d Table 1 Build platform types and properties author s experiences Platform Temperatu Successes Failures Other material res comments 3D Lami Room PLA and Double sided Weak Touch nated tempera TPE with tape ABS mechanical ply ture coating of construction wood glue stick leading to vibrations Ulti Heated Glass plate PLA and ABS warping The spray maker glass heated Wood with coating coating may 2 plate with a filament spray bed be reused Leap PCB board with plastic 90 C thicker many times frog up to coating coating and Printing ABS Creatr 100 C varnish higher bed needs glass spray bed temperature plate 75 C help preparations ABS with ABS Juice bed 100 C Giga Milled Room Blue Originally too No warping bot 5mm temperatu painters tape good adhesion or detaching thick re 3M and worked out by of parts aluminiu Kapton tape setting z axis experienced m plate successful offset 0 1mm even with with PLA very large and TPE rafts UPrint Dispo Air heated A raft of Reusing the Plates cost SE sable to around support
46. ours of Calibrate the load cells See Calibrating the printing or once every Load Cells on six months page 7 46 Every 2000 hours of Preventive maintenance Contact your Objet printing oronce a year visit by authorized support center service engineer Once a year Inspect the activated See Replacing the carbon odor filter and Odor Filter on replace if necessary page 7 48 As described in the manual the printer should not be turned off if in idle mode but should be kept idling for up to one week If the printer is not used for over one week a shutdown wizard should be run on it involving a flush fill cycle For shutdown the nozzles should be first emptied and then flushed with a cleaning fluid sold separately Objet 30 Manual n d 92 125 If changing materials flushing cycles are also necessary to have proper colors in the print if the color if changed Changing to a darker color the economy cycle will spend 65 grams 10 with one cartridge If changing to a clearer color the recommen ded High performance cycle will take 300 grams 10 when replacing one cartridge The washing cycle dumps the material in the waste collector 300 grams of material costs around 100 to 150 Objet 30 Manual n d 92 125 33 N level 3D printers Besides the materials used in this specific printer Stratasys of fers different materials like the flexible Tango materials However the usage of the
47. peed 10 300 mm s user definable Layer thickness 0 02 0 40 mm user definable Build volume 600 x 600 x 600 mm Files transferred via an microSD card or USB cable Build platform type Aluminium plate Used filament any thermoplastic of diameter 2 85 3 mm Title of thesis Leapfrog Creatr and Creatr XL Leapfrog n d Speed 10 60 mm s user definable Layer thickness 0 05 0 35 mm user definable Build volume 230 x 270 x 200 mm z height 500mm on XL Has to be constantly connected to computer via USB Maximum nozzle temperature 260 C Maximum heated bed temperature reached 100 C Build platform type Heated glass plate Used filament any thermoplastic of diameter 1 75 mm Stratasys uPrint SE Plus Stratasys uPrint SE n d Speed undefined similar to default Ultimaker Layer thickness 0 254 mm or 0 330 mm Build volume 203 x 203 x 152 mm Files transferred via Ethernet Windows 7 only Build platform type Heated build area by circulated hot air dis posable injection molded ABS plastic tray Used filament Diameter 1 75mm ABSplus in 9 colors only 1 color in the basic uPrint model and support material SR 30XL e Set timers for parts replacements and maintenance like the nozzles which are changed every 2000 hours or the 500h mainten ance routine to keep things in good condition Interface displays the temperatures the time of printing as Build material extruder 300
48. r TJ2000 and 95 C for TJ88 The materials are fed in a solid wax form to the printer Heaters are used to lower the viscosity of the wax and the machine has a 10 minute heat up period before printing Production of a similar material seems highly challenging The materials safety datasheet in Finnish reveals little about the char acteristics of the material whereas the English datasheets tell even less 3D Systems 1998 amp 2005 The machine was taken into use It had been standing in idle mode for unknown time The test print cycle functioned Con nection to PC was made with a private LAN connection Entry level 3D printers 64 bit Windows 7 was used to communicate with the printer with VirtualBox emulating Windows NT After making the prop er IP settings the printer responded to ping commands For file sharing a Windows private network sharing folder configura tions needed to be made After this it was discovered that the ThermoJet program crashed when trying to send a file to be printed The most probable reas on for this was some incompatibility error with the emulated Windows NT operating system Because of time limitations the software problems remained un solved The printer had been used several years ago for invest ment casting patterns successfully 36 Entry level 3D printers 3 3 3 ZPrinter 250 Figure 23 The Zprinter Powder printer pictured Notice the powder recycling sta
49. r friendly PreForm software It generates supports and estimates the successfulness of the prints automatically The automatic support generation is a critical feature in this printer Every trial made for this thesis to print without supports would fail Also the part orientation plays a big role and reorient ing may solve printing problems but introduce precision prob lems see later tests with the cuboids in this thesis Entry level 3D printers Figure 17 Form 1 at 0 1mm layers on left FDM printer at 0 1mm layers on right Formlabs Layer height n d The Form 1 s minimum feature size is defined as 0 3mm It is capable of much finer details than the FDM machines However overhangs and intricate features present challenges and may res ult in failures The printer needs to be maintained well and cleaned periodically The resin tank especially has to be kept clean Figure 18 27x magnification of the comparison Formlabs Layer height n d Entry level 3D printers Notable about the build processes is that the scanning laser works very fast in the x and y axes and print time depends mostly on the height of the objects printing many similar sized ones does not increase time notably whereas in the extrusion based printers the time increases linearly with the volume Unlike the extrusion based machines the pieces are printed solid as a default To have hollow pieces drain holes should be de signed i
50. riented cuboid from falling down Entry level 3D printers 4 1 1 Ultimaker 2 Both 0 4mm and 0 6mm nozzles were used in these tests It is hard to notice any difference between the two With default ori entation the connection point for the overhang would print stronger and a little bigger with 0 4mm nozzle while the 0 4mm nozzle might have a little better surface finish than the bigger one but this is hard to tell by visual inspection None of the prints came out perfect from the printer but reguired finishing The best results could be got with a small layer size and a 45 degree orientation with full 45 degree supports and probably a lower speed also The used filament may also play an important role as to not heat warp too much and to adhere well to the build platform because the surface area is low under the cubes Several methods were tried with the Ultimaker developing as more and more experiments were made First tests were done with PLA filaments There was White PLA supplied by Ultimaker and black PLA supplied by Weistek The machine using the white filament used a 0 4mm nozzle and the black a redrilled 0 6mm nozzle The machines were similar oth erwise and purchased during the same time Later on Natural ABS from Ultimaker would be used with the 0 4mm nozzle and a black spool of ABS from Bits from Bytes with the 0 6mm nozzle 45 Entry level 3D printers Table 5 Ultimaker 2 test settin
51. rint ABS 0 254 mm Not Sparse low 300 C Support fill SE Plus select density setting set Plus able to SMART option Print time Material cost generated by software 1h 1min per one 200 kg cube overall price around 500cm per spool Materials usage Model Material 6 9cm Support Material 1 51cm adding up to approximately 4 per piece 51 Entry level 3D printers Figure 37 Cuboid printed with uPrint before support removal The piece would easily break while removing if bent too much Table 8 UPrint SE Plus print results Machine Visual Caliber Finishing Finishing Material and inspection measurements operations supplier notes min max cube needed Uprint SE Layers easily 16 16 l1mm Surface has Support Plus ABS _ visible but Connections smooth feel material easily Plus by constant 1 5mm and no removed with a Stratasys finish disturbing knife imperfections Entry level 3D printers 4 1 3 Form 1 Plus The cube was printed with automatically generated supports After the pieces were printed out the part was washed in Isopro pyl Alcohol and the supports were removed with sidecutters Some sanding would be needed for a perfect finish Imperfec tions were easily visible in the transparent resin N N N n N BD A N c N TN MY Figure 38 The cuboid oriented 45 degrees w
52. s Accessed 8 10 2014 http taulman3d com 618 features html RepRap Forums n d Forum discussion Accessed 8 10 2014 http forums reprap org read php 1 137841 Bilbycnc PVA Fact Sheet n d Accessed 8 10 2014 http www bilbycnc com au AboutPVABilbyCNCFactSheet pdf Reprap wiki Polyamide n d Accessed 8 10 2014 http reprap org wiki Polyamide RepRap Wiki HIPS n d Accessed 1 11 2014 http reprap org wiki HIPS MatterHackers n d Webstore Soft PLA description Accessed 9 10 2014 https www matterhackers com store 3d printer filament 300mm red soft pla threeguarter kg Makerjuice Labs n d Hobbyist resins Accessed 9 10 2014 http www makerjuice com Formlabs Form 1 n d Form 1 tech specs Accessed 9 10 2014 http formlabs com en products form 1 plus tech specs Formlabs Layer height n d Comparison of printers Accessed 9 10 2014 http formlabs com en support help advanced layer heights Leapfrog n d Creatr product page Accessed 9 10 2014 http www lpfrg com creatr Cubify n d 3D Touch data sheets PDF Accessed 8 10 2014 http cubify com en Products LegacyDownloads Stratasys System Matrix n d Available as PDF Accessed 9 10 2014 http www stratasys com media Main Secure Material 20Specs 60 Entry level 3D printers 20MS PolyJet Material Specs System Matrix pdf Mcor technologies n d Matrix 300 plus product page Accessed 9 10 2014
53. se is limited to the more expensive and advanced Objet Connex family of printers The prices for these may be over a hundred thousand Euros The Objet 30 Scholar belongs to the Objet desktop family Stratasys System Matrix n d The material resin prices are high compared to any other printer used Prices per kilo range from 250 to 350 Support material costs 110 per kilo The materials containers have fixed last dates of usage and they have a RFID tag taped on their bottoms The Objet is the most expensive machine to use of all the print ers in this thesis Not many pieces were printed with it besides ordered and paid work The Objet can produce fine details and with supports it should be able to print almost any shape de sired Testing these capabilities more deeply was however left outside this thesis As seen in the Cuboid tests chapter later on the Objet seems to keep up to its promises as an accurate printer Figure 21 The WaterJet washing station Not pictured pressure water pump standard hardware store type and foot pedal for controlling the pressure N level 3D printers 3 3 2 Thermojet Figure 22 The Thermojet 3D printer The Thermojet is a long discontinued inkjet printer made by 3D Systems several tens of years ago The thermoplastic waxes used in the ThermoJet are particularly suited for creating patterns for investment castings The melting temperatures of the thermo plastic waxes are 55 C fo
54. seen as a waste of the support materials and printing both is time consum ing Figure 14 A complicated art piece being printed with lots of supports to facilitate the printing of a shell structure Total duration of this print was 40 hours pictured in halfway The uPrint has got much better reliability and constancy than the other extrusion based printers Overall the printer reguires less adjustments and tinkering with than the cheaper ones The ma chine is constructed of high guality machined or fabricated metal parts The supplied materials are expensive but of guaranteed high guality and packaged well 25 Entry level 3D printers There are occasional errors especially in the material feed sys tem There can be material breakages in the extruder In the worst case the printer may print without either one of the mater ials because of breakage This all requires attention from the user The uPrint software CatalysEX is rather limited in its customiz ability Open source software such as Cura have many more op tions for manipulating the parts and changing print parameters such as supports and the part s wall thicknesses This might seem negative at first but 1t does eliminate the time consuming exper imentation quite effectively This might be seen as positive or negative thing depending on the use The software automatically generates support structures to be printed The parts can be washed with t
55. t In this format the model is described in vertexes triangles that close the surface of the model This format is supported by all the programs involved in this thesis and should be so in any programs involved in 3D printers This stl file is sliced into multiple layers describing the toolpaths for the printers The slicing generates standard g code or a similar language that is then sent to the printer s electronics which control the different axis s and material deposition meth ods The g code is a standardized machine control language con sisting of lines of commands position coordinates and settings for the machine to read and operate accordingly Entry level 3D printers 1 2 1 Extrusion based FDM Fused Deposition Modeling a trademark by the Strata sys company PJP Plastic Jet Printing a trademark by the 3D Systems company May also be called FFF Fused Filament Fab rication or just plainly extrusion based systems Filament material Pinch roller O O feed system Liquifier m Nozzle tip ap x y axes Scaffold Platform z axis Figure 1 Schematic describing extrusion based systems Gibson et al 2010 145 Molten thermoplastic material is liquefied and then forced through a nozzle building up layers one after another Usually thermoplastics don t have a certain melting point and therefore the usable temperature range can be high even for the same ma terial Hig
56. t were printed with extruder nozzle diameter 0 6mm without blockages or misfeeds Material properties are similar to PLA but the objects are much softer and weaker Wood filament requires adjustments to the retraction settings on the printers to avoid getting leftovers between layer changes it flows guite differently from PLA or ABS With the wood filaments changing extrusion temperature has a minor effect on the color of the resulting prints Figure 6 3D printed owl in wood filament Thingiverse thing no 18218 N level 3D printers TPE Thermoplastic Elastomer Ninjaflex Soft PLA Extruded at 180 C to 230 C Flexible rubber like materials of different varieties Extruder has to be more rigid in construction for these filaments because the materials are very flexible The extruder idler pressure also has to be adjusted correctly to be holding it under just the right pressure to avoid squashing the fil ament Because of lower melting point and flexibility printing settings have to be adjusted correctly This has to be almost certainly done experimentally When bridging printing between perimet ers on top of nothing a build area fan may prove necessary to reach acceptable details MatterHackers n d Experiments to print a red soft PLA material were made A 150mm diameter ball intended to be used as a corned guard was printed with 5 and 10 honeycomb infill The resultant balls were not as flexible as expected
57. tion next to it The ZPrinter 250 builds up parts by using a binder material to adhere powder particles together to form up parts in seguential layers It uses cartridges from normal HP 2D printers HP11 and HP57 The HP57 cartridge is used to enable printing in 64 differ ent colors in the ZPrinter 250 This is not available on the cheap er ZPrinter 150 Entry level 3D printers The resulting parts are fragile and porous by nature and there are different methods that are recommended for infiltrating the part to reduce the porosity and increase the parts strength These in clude salt water spraying methods Cyanoacrylate super glue treatments or using a specific ZBinder compound Note that all links to the Zprinter 250 product page were redirec ted at the time of writing to the 3D Systems product page of their machine ProJet 260C Zcorp the original company was bought by 3D Systems in 2012 3D Systems press release 2012 Solheim Additive Manufacturing Laboratory in the Mechanical Engineering Department on the University of Washington cam pus has been developing the binders and the powder materials on their ZCorp ZPrinter and these results are available online on their Open3DP blog They have been successfully printing ob jects in salt powder and other ground up materials using custom binder solutions Open3DP Blog 2011a 2011b The ZPrinter 250 available for use had been unused for several months because of prin
58. ts stopping after couple of layers and the machine giving error codes such as Slow axis pos err Error 2303 0 After reviewing the ZPrinter user and service manuals it became apparent that the machine had not been serviced or cleaned ac cording to instructions at this time The service station especially was dirty and the axes hadn t been lubricated as instructed This was suspected as the source of the errors but at a service visit from 3D System s Finland s representative Multiprint Oy a faulty idler pulley was discovered A service component was ordered and the delivery took around 2 weeks Because of the shortage in time no test prints on the ZPrinter made it to this thesis However the prints should be accurate and gain some strength after infiltrating means curing with the ZBond or a Cyanoacrylate adhesive 38 Entry level 3D printers 3 4 Sheet Lamination Mcor Matrix 300 _ 05 Figure 24 The Mcor Matrix 300 3D printer pictured The Mcor Matrix works by gluing paper conseguently on top of each other and cutting the desired geometry on it after gluing The blade used is a titanium blade scheduled for replacement after cutting 7000 meters The price of the blades is running around 50 to 100 Euros The adhesives cost about the same per litre The Mcor must be left to idle to avoid blockages in glue deliv ery The machine does a service routine of applying one layer of paper every 2
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