3D Printing (in house) • Wilson Lab Wiki

How to use our resin 3D printer, wash and cure station in the WLI TOBIN.

We currently have an ELEGOO Mars 5 printer and an ELEGOO Mercury Plus wash and cure station.

What you will need:

.stl 3d file(s) of your part(s). Can be exported from many programs: e.g., Onshape, Autodesk Inventor) but should be exported as a format in mm (the default for the ‘slicing software’).
.goo print file to upload to the printer. This is the configured print as it will happen on the printer, and can have many different parts with different orientations. Currently the best software to use is Lychee Slicer https://doc.mango3d.link/
- NOTE: you can use CHITUBOX Basic for the Mars 5, but newer versions have removed the option to use anti-aliasing from the basic edition. This is quite useful for most of the things we print.

This software operates very similarly to CHITUBOX a screenshot of the very conservative settings for the resin/print when using the ABS-like V3 (grey, not green as it says in the screenshot)

To help the parts stick to the bed in our cold room this has an increased number of burn in layers, longer exposure time, and lowered lift/retract speed. It also has an increased cure time and a lowered lift/retract speed. This should not have a bad effect on fine details at this point and appears stable.
On the export tab you will likely want to use anti-aliasing, below are some reasonable settings for replicating the old CHITUBOX settings we used. These still require fine tuning, check the site for detailed descriptions.

Old Instructions for Mars 3 Pro Printer + Chitubox Basic#

Note: these are instructions for an old version of the printer but might be useful as a reference still

Starting settings are shown below. These values work well with our printer and Elegoo’s ABS-Like resin in white. You will need to change the “exposure time” and “bottom exposure time” values if you use a different color, type, or brand of resin. Reddit is a good place to check if you aren’t sure what values to use.

Drop your design into CHITUBOX
All imported designs will appear under the “File List” tab.
You can MOVE, ROTATE, and SCALE the design as needed.
If this is your first time printing the design, consider trying a few different rotations to see whether one prints better than the others. E.g., are there pros to printing the design on it’s side rather than face up?
Next, add support structures by switching to the support (right) tab. If you aren’t familiar with this process, it can be very helpful to watch some how-to/supports-for-beginners videos first.
A preview of your support structure is shown at the top of this tab
You can edit the shape and size of various parts of the support structure 1. Note: Hover your mouse over different values to see a description of what they correspond to 1. Small sphere-to-cone supports are often useful
You can auto-populate support structures by selecting “+PLATFORM”
You can also manually add supports (A) or remove supports (D)
If you would like to duplicate your design with supports, copy/paste the file in the File List tab
You can use the Auto Layout option at the top to evenly space your designs
Hit SLICE to get a preview of your printing process
Note the estimated print time
Save the sliced file as a .cbd file type (not .cbddlp) and transfer to a USB drive

Ensure that the printing plate (top) and the chamber (bottom) are in place and tightly fastened
Fill the chamber with your desired resin (~half way)
Note: The resin can be in the chamber for a few days max. If you plan on printing multiple days in a row it is okay to leave it out. However, be sure to dispose of the resin in the waste bucket and clean the chamber out thoroughly with isopropyl alchohol when you are done to avoid ruining the chamber.
Load your design into the 3D printer via USB drive
Print and wait! The progress of the print will be displayed on the front screen.

Very carefully scrape your design off the printing plate using the metal scraper tool on the shelf above the printing station
Be sure to avoid marking/scratching the surface, as this can cause future printing errors!
If you can’t the print off with the metal scraper, try (carefully!) sliding a razor blade under all of the edges of the print first.
Aggressively clean any remaining resin residue from your design(s) using Isopropyl Alcohol (99%, nozzle wash bottle)
Remove support structures and rafts by hand or by using the small cutting tools on the shelf above the printing station
Optional: you can use the Washing-Curing Machine to vortex your design with Isopropyl Alcohol
Remove the rotating platform and install the Isopropyl Alcohol chamber and metal basket
Place your design(s) in the metal basket and lower it into the chamber
Set the station to “wash” mode and clean for several minutes
Air dry when complete
Use the Washing-Curing Machine to cure your design with UV light
Remove the Isopropyl Alcohol chamber and install the rotating platform
Place your design(s) on the platform and cover with the UV protective chamber
Set the station to “light” mode and cure for 2min
If your design(s) feel clean and smooth, the cure is complete!
If your design(s) still feel a bit tacky, try curing in additional 2min increments until satisfied. Additional curing will cause white resin to yellow a bit - that’s okay.

Empty out the remaining resin into the waste bucket, use the scraper to remove as much as possible
Use a heavy amount of isopropyl to clean out the chamber thoroughly. This is important and can extend the chamber life dramatically.

Additional notes

If you’re worried that the base plate is not perfectly level, you can re-level it following the procedure in this video, athough you shouldn’t need to do this often: https://www.youtube.com/watch?v=W5u_g_zevLM. Leveling starts around 3:30.

It can be a good idea when printing parts to have them somewhat uniformly arranged across the left-right and front-back axes of the build platform. This is so that when the build platform is repeatedly pulling the part off of the bottom of the resin tank, it is less likely to become tilted. This is particularly important for parts with large surface area, for small parts it probably doesn’t matter.
When releasing the print from the build platform, this is often when it can become tilted. If you hold the platform by its edge rather than the ball-and-socket joint / mounting thing, you’re less likely to knock it out of alignment.
If parts are repeatedly failing, definitely check that the build plate is level and consider replacing the tank. Over time the film at the bottom wears down and gets scratched which results in prints not releasing well from the film.