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Re: 3D printed brake fluid cap

Tue May 30, 2017 12:08 am

the PLA should be fine. I would be worried about the lack of a proper seal/bladder.

you can print this on a $200 printer btw.

I would not be too keen to trust my brakes to it though :-) not without a lot more info.
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Re: 3D printed brake fluid cap

Tue May 30, 2017 6:54 am

Normally I'm all for 3d printing useful things but this is a bad idea. I know PLA will melt if left inside a hot car and I assume that under the hood can get just as hot if parked in the sun.

Also a few years back I was changing out the brake fluid on my motorcycle and accidentally spilled some on the fairings (body plastic), which are made of ABS. They started dissolving almost immediately.

So right off the bat, the 2 most-common-by-a-vast-majority printing materials are disqualified.

On top of that, as others have mentioned, brake fluid is hygroscopic - and 3d printed objects are rarely watertight, let alone airtight.

Spend the $13 now for a real part and save yourself a headache that's coming sooner rather than later. Keep an eye on the color of the brake fluid just in case it's absorbed a bunch of moisture already.
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Re: 3D printed brake fluid cap

Tue May 30, 2017 8:27 am

A great idea, but you could have gotten the original cap back by undoing 6 nuts, 6 plastic rivets, and removing the cover.

Just by undoing the ones at either end would have given you enough room to get in there with a stick and push it out.
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Re: 3D printed brake fluid cap

Wed May 31, 2017 11:27 pm

derkraut wrote:Is the brake fluid reservoir under pressure? I don't think so???

No, and it is important to note that brake fluid reservoir caps have a small vent to allow equalization of pressure with the atmosphere. With some type of baffle to prevent fluid leakage and dust ingress. It's a very small amount of air movement, but it's not a pressure-sealed system. Also as someone mentioned, a flexible bladder that is meant to accomodate transient changes. There's a bit of engineering in these little items.
I noticed you're still working with polymers.

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Re: 3D printed brake fluid cap

Mon Sep 25, 2017 12:40 am

Thanks for sharing. You can also find all information about printing material via You can find here difference between PLA ans ABS.

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