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Disk Brake Conversion - Pipe Flare Problem?

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Csarneson

Csarneson

Jedi Hopeful
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I am rebuilding my BN4 and converting to front disk brakes. After extensive research I've acquired the correct British-Mercury Capri calipers (from ebay.co.uk) and rebuilt them. The hole spacing fits perfectly with my 3000 caliper mounting plates so that part looks great. The pads are also the large late-3000 size and fit the BJ8 disks. I am having some problems figuring out the correct brake flares however. My brand new set of Moss brakelines has a different set of flares than the caliper uses. My new Moss pipes seem to have a double flare which matches my original pipes. My new caliper seems to have a girling bubble flare. Is that right because it's the exact opposite that I would have expected? Can I buy a set of 12" pipes with a girling bubble on one end and a double-flare on the other? Is there any other way of converting? I can't find any source based on my searches.


The stub pipe on the left came in the caliper. I think that might be a girling bubble flare. The pipe on the right is the new Moss pipe.
If you are curious here's my video on the brake conversion: https://youtu.be/oZS-fciLyUk I'm happy to provide other photos or answer any questions!


brake1.jpg
brake2.jpg


Thanks!

Chris
 
Ok, please check your threads on the fitting first. ATE might be metric threads. If you look into the port, you will see what type of end needs to be on the pipe end. Moss will not supply pipe to fit other the stock fitted calipers.
 
Denis Welch has SS hose sets for their replacement early calipers - which are metric. Maybe the same as yours?
 
google FED HILL, oxford, maine. ask for Tim. they do not make custom brake lines but supply brake line tubing and other components to people who do. i would think that he could recommend someone to make the short pieces that you require
 
It'll be a DIN bubble flare.
Good advice about Fed Hill in general but pretty sure they don't carry metric.
You might be able to use these SAE to Metric adapters if you can bend the Moss pipe to avoid interference with the wheel. (Amazon)
PS - I like to use 10 GA house wire to mock up brake lines like this.

Addendum - this catalog seems to have everything - including short adapter lines you were asking about:
https://www.agscompany.com/marketing-materials/catalogs/fluid-transfer-catalog.pdf
screenshot.1122.jpg

Addendum 2 -
I believe this outfit makes the Moss pipe sets. Also believe they'd make up custom pipes for you:
https://www.techna-fit.com/
 
Another solution would be to get a roll of 3/16" tubing, a tubing cutter and a flaring tool. Using the Ridgid 345 you can make both double and bubble flares.

HF sells cheap flaring tools. The one I bought made crooked flares but you might be able to get one that was straight. Worth buying just for the dies, which will work with the Ridgid.

My web gallery at the address below has pix and discussions of this.

There are a lot of YouTube videos about making brake flares.
 
Apologies to Rich Berman for borrowing his photo. IMO this shows there is plenty of room for an adapter fitting between the pipe and caliper:

FrontDiscPipeConfigBerman.JPG
Also, since you're going from a drum-braked BN4 - you shouldn't have any problem with the caliper fitting inside the wheel.

A plug for Rich's superb gallery of almost 1000 photos:
https://plus.google.com/photos/110087349657726745747/albums/5528813397849858337

Addendum: make sure you ask your supplier if the adapter will accept the Moss British-style tube nut. Some adapters require US style tube nuts which are threaded all the way down to the flare. If the British nut won't work, you might as well make a new brake pipe.
 
If you get the correct flaring tool to make the flair, most tubing cutters have a groove in the wheels so you can cut the tubing right at the flair. Do that to the Moss tube, slip on the correct nut and make the correct flair. Maybe even clean up the old nuts and use them.
 
If you're interested in doing your own flares, let us know and we can pass along some more dos and don'ts.

FWIW I'm of the opinion that investing in a decent flaring tool is a worthwhile thing for a project car and will justify itself in the long run.
 
You guys are amazing! I'm not quite sure which direction I will ultimately choose. It does look like the caliper is metric. I didn't expect that. In the ideal world I would make my own flare with a new end but the adapter might be easier. I'm going to check out both options! Thanks again! I'll let you know what I decide to do.
 
You guys are amazing! I'm not quite sure which direction I will ultimately choose. It does look like the caliper is metric. I didn't expect that. In the ideal world I would make my own flare with a new end but the adapter might be easier. I'm going to check out both options! Thanks again! I'll let you know what I decide to do.

Chris
 
i just finished installing a dual circuit system on my 1959 bn6 with all new pipes. and, i can say that investing in a good flaring tool generally saves lots of headaches. i bought an Eastman tool and it is a one shot deal. i think that i threw away my harbor freight tool!
 
Go to Advance auto and try a metric brake line in your caliper, if it fits, tell me the Advance part number.
Send me the "ends with the tube ", from your old connections so I know what you need putting on the other end.
Tell me how long you need them to be.
I'll make up two lines for you.
I bought the brake line tool from Eastwood and it is proving very useful.
 
I have the Harbor Freight flaring kit, it works, but you have to use a combination of finesse and brute Force to get it to work right. I would probably buy a higher quality kit if I were to do it over. Sounds like you have a good offer to get it taken care of, it is very useful to have a flaring tool (and a tubing bender).
 
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