Powder Coated Calipers

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DavidE9
Posts: 183
Joined: Apr 22, 2012 1:29 AM
Location: Encinitas (LA is a shit show right now)

Powder Coated Calipers

Post by DavidE9 »

Hello:
I recently had the calipers on my big brake conversion powder coated. In the attached photos, hopefully you can see two things:

The outer surface of where the brake lines connect is not flush. There is a lot of paint which I fear makes it hard to get a solid connection even with a crush washer.
The area on the caliper where the dust cover sits is also covered in a bit of paint.

Should I be concerned ? Im tempted to send them back out to be re-done by another shop (https://www.biggred.co.uk looks to know what they are doing)

https://share.icloud.com/photos/0a1EoR5 ... vIAx9OQ4Tg
https://share.icloud.com/photos/065avVD ... aFjPeaeRjg
https://share.icloud.com/photos/0d01X3s ... ua3q9o2-Aw


TIA
Philo
Posts: 2166
Joined: Feb 12, 2006 12:00 PM
Location: Long Beach, CA

Re: Powder Coated Calipers

Post by Philo »

David, I sent these photos to the Pros at Caliper HQ in Signal Hill. I'll post their reply shortly.

There's lots of competent powder coaters in CA however few know how to properly mask calipers. Reach out to Graem or Dan at Caliper HQ. https://caliperhq.com/contact/
gadget73
Posts: 1176
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: Powder Coated Calipers

Post by gadget73 »

can't have paint where the crush washer sits. Appears to be recessed too, otherwise I'd say just take a flat file to it and shave it down. Might do that on the face of the caliper where the dust boot goes though.
Philo
Posts: 2166
Joined: Feb 12, 2006 12:00 PM
Location: Long Beach, CA

Re: Powder Coated Calipers

Post by Philo »

From Caliper HQ..

"Yes, that surface needs to be filed down but it’s tricky because you don’t want to file any of the aluminum off which would cause a leak. The caliper could be masked and only expose that area could be glass bead blasted to remove the excess powder. I’ve seen powder that is adhered so well that glass bead wouldn’t remove it. Powder coating over spray is a total PITA and not masking wastes a lot of labor hours."

If I had these calipers I'd jig them up in a mill and use a reem to clean up the crush washer surface. For the overspray in the piston area I'd use some small files to try to clean it up.
gadget73
Posts: 1176
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: Powder Coated Calipers

Post by gadget73 »

yeah a quick touch with an endmill would clean up the sealing surface very well. I'd be slightly leery of blasting it for fear of it roughing up the surface too much to get a good seal. Every caliper I've ever seen has a flat milled surface where the washers go. Those copper washers only take up small surface imperfections.
DavidE9
Posts: 183
Joined: Apr 22, 2012 1:29 AM
Location: Encinitas (LA is a shit show right now)

Re: Powder Coated Calipers

Post by DavidE9 »

Well, crud. Sounds like these are trashed now.

Thanks for the help.

-D
Last edited by DavidE9 on Mar 22, 2023 1:41 PM, edited 1 time in total.
gadget73
Posts: 1176
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: Powder Coated Calipers

Post by gadget73 »

not trashed, just have to be fixed properly. Annoying but not the end of the world.
DavidE9
Posts: 183
Joined: Apr 22, 2012 1:29 AM
Location: Encinitas (LA is a shit show right now)

Re: Powder Coated Calipers

Post by DavidE9 »

Hello:
Can anyone recommend an online source for brake line crush washers ? Maybe the size/PN too ?

TIA
Philo
Posts: 2166
Joined: Feb 12, 2006 12:00 PM
Location: Long Beach, CA

Re: Powder Coated Calipers

Post by Philo »

Any NAPA store should have a selection. I'd call around. Also, hydraulic shops will have them.
gadget73
Posts: 1176
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: Powder Coated Calipers

Post by gadget73 »

probably can find this info at realoem if you look up the vehicle they came from.
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