Printers

We have two models of printers from Formlabs at EPIC. The Form2 printer is an SLA printer, which stands for Stereolithography. The Form3 is a LFSLA, which stands for Low Force Stereolithography. These printers use a photopolymer resin tank and a movable laser to cure each layer. The layer height ranges from 0.025mm to 0.30mm and the selection available will vary with the type of resin you are printing with. For most prints 0.1mm layer height is a good balance between surface smoothness and print time so this is our default for prints. For further details on each resin available from Formlabs please visit their Resin Selector website. The resins we currently stock are listed in the table above. If you wish to use a resin which we do not stock please contact us, you may have the option to purchase the resin and resin tank and provide them to EPIC to complete your print requests. Form2 printers are not currently in circulation, they are for the experimental Ceramic resin use only.

After printing is complete the SLA parts go into a solvent bath to remove excess uncured liquid resin and then undergo a secondary UV light and heat cure process to reach their final material strength. Parts will continue to cure if exposed to UV light so a UV protectant coating is recommended for parts used as functional products. Due to the printing method resin printers always produce solid parts. This means the parts are water-tight, however they may absorb chemical solvents or interact chemically with castable resins. These parts typically require a support lattice in order to print successfully and remove from the build platform without failure. The support lattice may either be removed using wire snips or snapping them off by hand, depending on the resin. The material properties for the resins in stock at EPIC range from a soft flexible material to a rigid glass infused material. Formlabs provides ‘white papers’ on each material, including their material properties, on their website.

For resin prints please pay attention to the design constraints outlined by Formlabs in their Design Specs blog and SLA Tolerances (PDF). We will generally contact you regarding a print request if regions of your part seem too thin to print or holes seem too small. We cannot always tell if the resin will wash out of openings completely before they go into the post cure process.

Form2 printers apply more force to the part as it is printing so these are restricted to parts under 100mL and 1cm wall thickness. Form3 printers can print larger parts and handle up to 350mL volume depending on the geometry. If your part is too large for SLA, and cannot be traditionally fabricated, then FDM is a good option. If you are looking for transparent parts, Form3 will be a better option than Form2 but will still require polishing for truly clear parts. Failures in resin parts usually occur when parts are too thin, when the tank ages, when parts are not supported well enough so they tear and stick to the bottom of the tank, or when parts warp during curing.

Queue Speed:

• We have 6 Form3 printers (our Form2 printers are semi-retired and reserved for ceramic prints only).
• Please submit one request per resin type.
• Each resin type requires its own tank, so we have one printer per resin. So your request cannot go on more than one printer at a time.
• Once a place in the queue is available most parts will take a day to print and if they are a small layer height (0.05mm, 0.025mm) they may take more than a day to print.
• Queue priority will be given based on our Policies and Prioritization page.
• You can check the status of your part, its place in the queue, and communicate with staff via our web portal located at bu.edu/epic/3d

We have 9 Bambu Lab printers at EPIC reserved for print requests through our web portal. These printers have an enclosure, a heated bed and a material management system (AMS). The print is able to pause when filament runs out and use the AMS to load a new spool (if there is a duplicate spool available). We use the Engineering bed which is a flexible spring steel with a PEI powder coating. Bambu Lab makes their own slicer which may be used to prepare the parts for printing. When setting up the parts for printing the correct printer model, nozzle size and filament in the material management system must be selected. The slicer allows you to input custom settings for layer height, infill percentage, speed, temperature, etc. Our P1S printers use 0.4mm steel nozzles and are setup with PLA or TPU filaments. The X1C printer is designed for the composites which wear down the printer components more quickly. Our X1C is setup with a 0.6mm hardened steel nozzle for printing CF filled filaments, when those are not installed its typically printing PETG. The Bambu Lab printers are best used for prototyping. Parts can hold water if they are printed with 0.2mm layer height or smaller. High infill parts may still have bed adhesion and layer adhesion issues depending on the geometry. These printers are much faster than the previous class of FFF printers so we are utilizing a larger nozzle to prevent frequent clogs with composite and soft TPU filaments rather than to speed up printing time. PLA is significantly cheaper than the other printing materials so larger parts will be a more reasonable cost. The Bambu Lab printers do offer the option of printing a support material layer between the supports and the part for much easier removal of supports and a higher quality print surface. We do not use support interface material as a default option because the printer only has a single head so the number of material changes drastically increases the print time and material usage. Multi color prints are also possible but face the same issue. While the technology is improving these printers can still fail due to bed adhesion, parts warping from heat, nozzle clogs, filament binding up on the spool, parts printed without sufficient support, among other reasons.

We also have 6 Bambu Lab X1C printers available in our First-In Cart for self-guided printing. Visit our page on the First-In cart for more information on using these printers.