Ring Fitting, Banjo Bolt, Calipers

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Hugo Karasawa
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Ring Fitting, Banjo Bolt, Calipers

#1 Post by Hugo Karasawa »

Is it possible to use steel tubing instead of the ring fitting and banjo bolt in the rear calipers ?
Enclosed is a picture of what I mean.
Or why are the ring fitting and banjo bolt needed?
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ring fitting Caliper straight tubing.jpg
ring fitting 01.jpg

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Ron LaDow
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Re: Ring Fitting, Banjo Bolt, Calipers

#2 Post by Ron LaDow »

Well, the drilling and threading for metal brake lines are designed for use with the upset end of the tubing; that's how it seals. The banjo fitting seals with crush washers.
I doubt the former will seal in the caliper housing.
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Curt Dansby
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Re: Ring Fitting, Banjo Bolt, Calipers

#3 Post by Curt Dansby »

Ron is 100% correct. Look at he machined face on the caliper body that corresponds to the crush washer interface. For the direct connection coupling you show there would need to be a female receiver for a flare fitting interface in the caliper which is not there. I think you could prove this pretty easily by putting some compressed air at the open end of your brake line and feeling the air leakage at the caliper threaded connection.

Curt

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Ron LaDow
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Re: Ring Fitting, Banjo Bolt, Calipers

#4 Post by Ron LaDow »

Curt, I think we are both more technical and detailed than the reply needs, so here:
1) A brake metal tube needs to seal in a female 'socket' designed for that use; no other threaded hole will do.
2) A banjo fitting needs to seal 'crushing' washers on both sides of the 'banjo' on to machined surfaces; no other threaded hole will do.
Never the twain shall meet.
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Hugo Karasawa
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Re: Ring Fitting, Banjo Bolt, Calipers

#5 Post by Hugo Karasawa »

Ron and Curt,
Thank you for your answers.

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Brian R Adams
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Re: Ring Fitting, Banjo Bolt, Calipers

#6 Post by Brian R Adams »

Ron LaDow wrote: Thu May 24, 2018 1:06 am Curt, I think we are both more technical and detailed than the reply needs, so here:
1) A brake metal tube needs to seal in a female 'socket' designed for that use; no other threaded hole will do.
2) A banjo fitting needs to seal 'crushing' washers on both sides of the 'banjo' on to machined surfaces; no other threaded hole will do.
Never the twain shall meet.
Ron, where may one obtain the crush washers for a brake banjo fitting? (In my case, a fitting for the short connector pipe between the front brake cylinders. I don't find them at our usual sources.)

Brian
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Brian R Adams
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Re: Ring Fitting, Banjo Bolt, Calipers

#7 Post by Brian R Adams »

Update: I found the copper crush washer 900.123.005.020 at several 356/912 parts sources. Stoddard/NLA, my first stop, doesn't have that part number, so I figured they might be rare.
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Dick Weiss
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Re: Ring Fitting, Banjo Bolt, Calipers

#8 Post by Dick Weiss »

Notice that there are 2-sizes of the copper crush washers required;
12x16 900 123 005 20 (outer) & 10x16 900 123 004 20 (inner)

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Jacques Lefriant
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Re: Ring Fitting, Banjo Bolt, Calipers

#9 Post by Jacques Lefriant »

Hi Hugo
911s delete the banjo bolt in the rear. your caliper probably has the provision for the double flange meatal line but it maybe deeper than normal so you might have to use a longer hollow bolt on the metal line. or machine the seating surface to allow the metal line to seal. I am not recommending this action but answering the theoretical question.
j
 

Jeffrey Leeds
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Re: Ring Fitting, Banjo Bolt, Calipers

#10 Post by Jeffrey Leeds »

You might consider BelMetric: belmetric.com

They are happy to deal in small batch orders. https://www.belmetric.com/drain-plugs-a ... -c-11.html
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WilliamVaughan
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Re: Ring Fitting, Banjo Bolt, Calipers

#11 Post by WilliamVaughan »

regarding the two sizes of SOFT Copper seal washers: Are you sure Stoddard doesn't have them? I believe I just bought them from Stoddard for the 912. Those banjo fittings are standardized and used over many years.

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Martin Benade
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Re: Ring Fitting, Banjo Bolt, Calipers

#12 Post by Martin Benade »

I am not familiar with the 911 but it may either have an adapter with a ring seal that the brake line screws into, or a brake line made to fit the hole, sealed with a copper washer. Or the way Jacques said, he knows way more than me. Several ways to accomplish this.
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Tim Berardelli
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Re: Ring Fitting, Banjo Bolt, Calipers

#13 Post by Tim Berardelli »

Macmaster-Carr has both of those size copper washers.

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Vic Skirmants
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Re: Ring Fitting, Banjo Bolt, Calipers

#14 Post by Vic Skirmants »

I get them from Stoddard's. No problem.

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Brian R Adams
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Re: Ring Fitting, Banjo Bolt, Calipers

#15 Post by Brian R Adams »

Robert Vaughan wrote: Mon Oct 07, 2019 5:33 pm regarding the two sizes of SOFT Copper seal washers: Are you sure Stoddard doesn't have them? I believe I just bought them from Stoddard for the 912. Those banjo fittings are standardized and used over many years.
Yes, Stoddard has them. I looked at NLA and they didn't list them, so I assumed Stoddard (same company) would not. Brad Ripley contacted me, pointing me to Stoddard's washer page. He said they would add this item to NLA's page soon.

Here are several washers. The ones I am interested in for drum brake cylinders are #13 and #15 on the drum brake cylinder drawing:

Washers:

https://www.stoddard.com/catalogsearch/ ... 900-123-00

Drawings:

https://www.stoddard.com/porsche-356/br ... -356b.html

Brian
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