Caliper half seals unobtanium no more

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raygreenwood
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Joined: Wed Jan 22, 2003 3:01 am

Caliper half seals unobtanium no more

Post by raygreenwood » Fri Aug 09, 2013 1:40 pm

Gentlemen (and the occasional lady).....I have found a source to provide the correct material (EPDM) and durometer (70 duro) and almost identical sizing for the small caliper half sealing o-rings.

20 years ago I could have these made at will by a company I knew....have used them repeatedly...and they work perfectly as factory allowing a full rebuild and peace of mind on ATE calipers for 411/412/914 and type 3.

The minimum order quantity is 100 pieces @ $1.95 per part. I will be ordering these regardless of who is in....they take 4-5 weeks to get here. Will be selling them just at cost to get my investment back.

A caliper pair requires 4 of them. Anyone in?

The bore as measured in four different calipers:

.422" to .430" OD
.065" to .073" deep

The ID varies depending on amount of crush because the material extrudes inward...but is nowhere near the fluid hole and averages .270"

The seal itself swells ever so slightly and was found when wet to be .428"-.433"

the thickness was .080-.085" wet and .075"-.078" when dried.

These seals are going to be:

.426 +/- .004" OD
.076" +/- .006"
.255" +/= .006"

They should fit and compress just fine. They do not require more than about .003" to .004" compression to seal a rectangular profile o-ring in a bore as long as the OD is very close.

Let me know. I will be ordering Monday. Ray

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19super73
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Re: Caliper half seals unobtanium no more

Post by 19super73 » Sat Dec 28, 2013 3:26 pm

Any updates on this. I PM'd you on TS with my interest.

Steve Arndt
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Re: Caliper half seals unobtanium no more

Post by Steve Arndt » Sat Dec 28, 2013 3:46 pm

Ray hasn't logged in since Dec 1st. I hope all is well for him!

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19super73
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Re: Caliper half seals unobtanium no more

Post by 19super73 » Sat Dec 28, 2013 9:51 pm

And Nov 13th on TS....

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raygreenwood
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Re: Caliper half seals unobtanium no more

Post by raygreenwood » Sun Mar 23, 2014 5:19 pm

My apologies to all. Since about thanksgiving i have had to purposely stay away from all distractions. My work took an ugly turn....worse than its been in two years....80+ hour weeks and much isanity with a new boss at my company.
I have unfinished projects for several people here ....and owe many an e-mail answer.

As of March 7th i resigned my current position living and working in Des Moines Iowa....to take a much better opprotunity at an expanding company in.....Connecticut!

Last week was my first week and its a high speed high pressure job (as usual :lol: ) It will be about 2-3 months until everything gets stable and I get moved in. Lving in a hotel and company apartment until then....and just tyring to get my head straight.

Bear with me! I will be back. Ray

On the caliper half seals....they work great and when I get all of my stuff together over the next few weeks I will get them in the mail. I got two sets installed to pressure test (around mid november) and have had one soaking in DOT 4 to make sure there are no issues. None so far. Sorry for the delay.

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MGVWfan
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Re: Caliper half seals unobtanium no more

Post by MGVWfan » Thu May 15, 2014 4:40 pm

Hey Ray, your post reminded me...I've got a set of those ATE "medium" calipers off a BMW 3-series, the ones that need something like 40 thou shaved off the mount bosses...I don't remember if it was you or someone else advocating that swap, so just asking, better to rebuild the stock calipers or go with the modified BMW ones?
Lane
73 VW 412 (the Nomad, dropped valve seat land now, argh!)
67 MGB (Abingdon's Finest)
76 Plymouth Duster /6 (runs like a top)
99 New Beetle 2.0 (never gives any trouble)
04 Golf TDI (45 MPG)
09 JSW (love it, love it, love it!)

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