Introduction: 3D Printed Check Valve
I've been experimenting for some time on how to create 3D printable check valves. This check valve utilizes a silicone disc and ball. This silicone piece is inserted mid-print, minimizing the chances of air escaping in other spots. Once fully printed, the silicone part is put in a sprung position, allowing it to be pushed by air in one direction but not the other.
Materials:
- PLA or ABS
- Ecoflex 00-30 Silicone
Tools:
- 3D printer
- Cup
- Spoon
- Thin screwdriver
- Fine-tipped tweezers
- Flush snips
Step 1: Casting the Check
Print SealMold.stl. You can find the .STL files for this project here.
Mix some Ecoflex 00-30 silicone in the cup with the spoon. Ecoflex is a 1A:1B silicone, meaning you should mix an equal amount from each bottle. You do not need much for this project.
Fill the mold with the silicone and let it set for 4 hours.
Step 2: Demolding the Check
After the Ecoflex has cured for about 4 hours, peel the edges of the disc part of the check and pull it out gently.
Step 3: Inserting the Check
Print ValveBody_supported.stl (or ValveBody.stl if you want to use your own supports) the same way as the mold. (This is to reduce cracks so air does not escape). Pause the print before the top fillet starts. If you are printing at .2mm layer, this should be around layer 190. If your printer does not automatically move it's head out of the way when paused, move it manually. Use the thin screwdriver to clear the hole on the inside of the valve of any stringing or blobbing. Insert the tail of the check into the hole and lower down the whole check. Press down the disc of the check with the screwdriver a bit. If you moved your printer's head manually, move it back now. Continue the print to completion.
You can download the .STL files for the project here.
Step 4: Finishing Touches
Use the fine-tipped tweezers to grip the the tip of the tail of the check. Pull it as far out as you can and snip it with the flush snips. Be careful to not snip the ball.
Step 5: Use
To use the check valve, connect 1/4" tubing to it's ports. An arrow shows which way the air flows.

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Full Spectrum Laser Contest 2016
7 Comments
3 years ago
Cool project.
The STL files are here: https://www.thingiverse.com/thing:1396435/files
Would be great to share the sources files (hopefully in FreeCAD or OpenScad ^^)
6 years ago
This is cool idea, total done from scratch :)
Reply 6 years ago
Thanks!
7 years ago
Hey Aidan,
Another nice 'Ible. Saw you on Adafruit's S&T again! XD Nice job on your check valve buddy!!
This reminded me of some I had made similarly. With mine I used an airsoft bb as the 'check'! I copied the √valve I had salvaged from a cheapy Walmart aquarium air pump! I 3D printed the shell and inner cage. I then placed the bb inside and CA glued it together! I was able to make lots for pennies! Well cheers Buddy Good Job Keep it up man!!!
Reply 7 years ago
Thank you very much man! Your valve sounds interesting as well!
7 years ago
Very cool! I just love how much more I can do with 3d printing since discovering the concept of pausing mid-print and enclosing something. The check valves are a cool idea!
Correct me if I'm wrong, but I think "1A:2B" does NOT mean equal amounts of both components (step 1), but rather 1 part of component A with 2 parts of component B, or not?
Reply 7 years ago
Thank you very much! Good catch, you are correct. I meant to say 1A:1B. Thanks for that.