Elegoo Saturn Exhaust System

thingiverse

***Update 11-3-21*** Added Level foot spacer for original leveling feet ***Update 9-16-21*** Added note about vibration from fan ***Update 7-4-21*** Added gasket (TPU) model for manifold, better photos, and level foot (TPU) model ***Update 7-2-21*** Revised Saturn Bracket. Made stiffer and with a longer base. This is an exhaust system for the Elegoo Saturn. No more fumes. Print the manifold, and two brackets, but mirror one of the brackets so there is a left and right. See the photos for reference. The 3mm hole patterns on the mirrored brackets, when assembled to the base of the Saturn, should match up with the hole pattern on the tabs of the manifold. If you are using the mcmaster-carr 2.5" exhaust hose like I did in the photos, also print the exhaust adapter file. If using another type of hose or duct, you will need to design a different mount for it. It will have to have a 50x50mm hole pattern to accept the 4mm screws used to mount the DC fan. Note: If you have excess vibration from the fan into the Saturn, you can print 2 more exhaust adapters, and place the fan away from the manifold, somewhere along the hose length (splitting the hose into two sections). The two additional exhaust adapters you printed will sandwich (using 4x 4mmx35 or 50 screws and nuts) the fan and join the two hose sections together. (You will now need 4x 4mmx16 screws to connect the third exhaust adapter to the manifold). This will isolate the fan from the manifold and not transmit vibrations to the printer. Make sure to leave a fairly long length between the fan and the Saturn manifold, at least 5 feet is good (the length from the fan to the outdoor exhaust connection is immaterial). If the distance between the fan and manifold is too short, it may not attenuate the vibrations well enough. Finally, you can take this same approach with different hose styles, but you'll have to design your own adapter. Print the manifold gasket in TPU. Fit the TPU gasket to the manifold. You'll need 4x 4mm heat set inserts, 4x 4mmx35 or 50mm screws (depending on thickness of purchased fan). If you want leveling capability in the rear of the printer, you'll need 2x 5mm heat set inserts and 2x 5mmx30 screws (for the bracket print). You'll also need 6x 3mm heat set inserts and 6x 3mmx16mm screws to mount the manifold to the brackets. The brackets mount between the original rear leveling feet and the base of the Saturn. The leveling feet will no longer be able to level the rear of the printer as they have to be tight to the brackets to support the manifold and keep it tight to the back. But the brackets provide for 5mm screws for leveling the rear of the printer. Print 2 of the TPU level foot prints to put over the end of these 5mm screws so they don't scratch the table your printer is on. To install them, self thread the 5mm screw into the TPU foot (after threading the screws through the brackets). It's actually easier to do this with the brackets already mounted to the Saturn (via the original leveling feet), so you can use the weight of the Saturn to help with the self threading process (it requires a lot of downward force to do it). When using the 5mm screws to level, they will provide a counter moment which will improve the stiffness of the brackets, and relieve some stress on the original leveling pads. When you attach the manifold to the brackets, there will be a gap between the mount tabs of the manifold and the brackets, this is by design. As you tighten the 3mm screws it will preload the manifold and press it firmly into the back of the printer to maintain a seal (as it pulls back on the brackets). Once the 3mm screws are gently tightened and the manifold and tpu gasket are held against the back of the printer's base without being wobbly to the touch, that is tight enough. If you over tighten the 3mm screws it puts a lot of stress on the original leveling feet. Finally, run your finger nail against the outer edge of the tpu gasket and push it into your Saturn's base all around the perimeter of the manifold. This will allow for any slight warping of the manifold base edge, and places the gasket in a position to fill up any seams. You'll also need a 60mm square fan (Outside dimension) with 50mm square hole pattern. Try to get one with the highest CFM you can find. A 12v or 24v dc fan is a good choice, and then you'll need a DC power supply that can vary the voltage to control the airflow to your liking. Also a on/off switch is a nice option on the power supply. Digikey is a great source for DC fans. I purchased MQ6038E12B-FSR 1570-1137-ND FAN AXIAL 60X38MM 12VDC from digikey. This fan produces nearly 70 CFM !!! Way more than we need but never a bad thing to have too much potential. I also purchased this DC power supply from Amazon: SHNITPWR 60W Universal Power Supply DC 12V. This supply can vary the output from 3 to 12v and has an on/off switch. If you wish to use the exhaust adapter stl file, you need to buy McMaster-Carr 2.5" hose for exhaust fumes. (expensive). (If you need the wall mount for this hose, it is here: https://www.thingiverse.com/thing:1178146 ). This hose is excellent but 11 feet costs about $110. But it is the last duct you'll ever need it will never crack or leak. p/n at McMaster-Carr: 5398K12 . I just uploaded another wall mount for this hose. It has two inputs with valves, great if you have two printers. You can find it here: https://www.thingiverse.com/thing:5104134 Note 2: If you run out of adjustment of the front leveling feet (original ones on your Saturn) when leveling, you can print two of the Saturn_Levelfoot_Spacers and it will stack under the original feet and give you 6mm more height to start with. This works fantastically well. The only time there will be the smell of resin is when you take off the UV cover. Summary of operation and why this works: In order for the exhaust system to work you must leave the UV cover on. At the base of the Z axis drive behind the vat are small openings that lead into the base. When the electronics cooling fans are on, a venturi effect is created dragging a small amount of the fumes from inside the UV cover through those openings and then they travel with the cooling air and out the back. When you don't use an exhaust system like mine, this is how 99%+ of the fumes enter your work area. The cover is pretty well sealed, very little fumes will escape from there. Also when the the two cooling fans are on, (along with the exhaust fan in my design), a slight pressure drop is created inside the UV chamber. As a result, even the tiny amount of fumes that might have escaped between imperfections in the UV cover and base, cannot exit, since air from the outside will travel though those cracks instead (due to the lower pressure). This exhaust system is very effective. I use water washable resin (which smells awful), and I am in a small air conditioned shop (sealed). When I printed without this exhaust system in place, the fumes were unbearable and likely dangerous to breath. With the system in place, I can't smell any fumes at all after an overnight print. Night and day difference. Also because we are not directly exhausting fumes from the UV chamber, we are not impacting the temperature significantly inside the chamber, which could reduce printing quality, or even cause a failure. A ventilation system that draws directly from the UV chamber is a huge negative. This system gently removes the fumes from the UV chamber so we are not introducing a ton of cool air to the printing area. The bulk of the airflow just cools the electronics, which is a positive from both perspectives. Still not convinced? The ELEGOO carbon filter for the Mars printers is located in that printers base to remove fumes. The design of these printers is very similar. That should tell you where the bulk of the fumes come from in an ELEGOO style resin printer.