3D print - Threaded pressure bleeder adapter

My project this week was to design and 3D print an adapter to make pressure bleeding our brakes easier. Instead of using the cumbersome "universal" brake reservoir adapter I made a threaded one. The idea is to use your air bleeder pump or air compressor as an air source only, not to flow brake fluid. IOW, bleed the brakes, not letting the reservoir empty, pop off a quick disconnect and unscrew the cap to refill, then repeat until done.

I haven't tested this yet on my truck but it should work. If you get to it before I do let me know how it works or if you have any suggestion for improvements.

The post printing photos aren't showing up yet on Thingiverse but should soon.

Oh, the cap I designed uses standard Euro brake reservoir threads so it should work on those cars directly without the collar and threaded adapter parts.

Toyota Tacoma brake pressure bleed adapter by raylo32 - Thingiverse

 

I just tested this on my brake reservoir using the small Motive bleeder container and it works, but it does leak down slowly. Probably still time to bleed one brake but I'd like it to be better. Almost certainly the TPU being a bit too rigid to seal but I am not sure if it is the collar where it is clamped to the reservoir lip or the cap gasket. Next step will be to replace the cap gasket with a piece of rubber and then if that doesn't work maybe print another male adapter and glue it into a piece of 1.75" ID radiator hose or plastic tubing. That should be soft enough to seal better on the reservoir lip. OTOH if you had a bigger pressure pump like a garden sprayer this leakage would be even less of an issue to use as is. In the future I'll probably revise the TPU collar to leave room for a thin piece of rubber or even a neoprene collar to line it in the area where it meets the Tacoma reservoir lip.

 

Just an update for this. I abandoned the original work in progress TPU design in favor of a better one that uses some neoprene to make a better seal. Easier to print, and simpler to use. Find it here: Toyota Tacoma Brake Pressure Bleed Adapter by raylo32 - Thingiverse

For the air connections use 1/4" ID tubing like what comes with pressure bleeders and make them up with these or similar medical air connectors for 1/4" ID tubing. Something like this: 40AC Series - Acetal Quick Couplings - Medical Quick Disconnect Couplings - Medical Component Products (industrialspec.com)

Here is a pic in use with a Motive pump and Euro cap. You can also print the cap but this one has a swivel which makes it easier to use:




Here is a pic of an adapter I made to run this off my shop compressor (run it up to about 15 psi and shut it off, use the air stored in the tank). Put a male medical quick connect fitting on the hose for your cap so it can connect to whichever air source you want.