thoughts on copper brake pipes.

[chapel gate]

spent today under the cruiser, aah the perfect sunday, lifes good..

I'm replacing all of the brake pipes and the flexi hoses, but doing it in two stages. all genuine stuff. the two long pipes that come out of the lspv then go down the side of the tank to the front of the vehicle i decided to splice for now and replace the whole length as part of stage two next year sometime.

anyway, getting to the point all we had in the workshop was copper, ive never thought twice about using the stuff but a quick read up and a lot of opinion is not to use it.

its cut, flared and bolted up now but thought i would ask what thoughts are on the subject on here?

 

[clivehorridge]

spent today under the cruiser, aah the perfect sunday, lifes good..

I'm replacing all of the brake pipes and the flexi hoses, but doing it in two stages. all genuine stuff. the two long pipes that come out of the lspv then go down the side of the tank to the front of the vehicle i decided to splice for now and replace the whole length as part of stage two next year sometime.

anyway, getting to the point all we had in the workshop was copper, ive never thought twice about using the stuff but a quick read up and a lot of opinion is not to use it.

its cut, flared and bolted up now but thought i would ask what thoughts are on the subject on here?

I've used it a lot in the past on regular cars with no issues.

Copper is softer and more prone to wear if it's rubbing against something else.

I used to take care to clamp it well especially on longer lengths. As protection, I used to use split rubber tubing, or not split if you know where and how many you need before flaring the ends.

Avoid long 'wavy' bends before the fitting, because waggly loops can tend to fracture at the clamped flare. Most of this is theoretical, because I've never seen one crack, others may tell a different story.

I would use it again, no worries.

 

[StarCruiser]

It's used for Refrigeration and takes high pressure in the order of 400 psi so should take twice that before bursting. I'm not sure what sort of pressure a Cruisers brake system could get to under sudden heavy braking but it could overstress it in theory. Bundy tube is better which is copper coated steel and more like the right stuff. Cheaper too.

 

[clivehorridge]

It's used for Refrigeration and takes high pressure in the order of 400 psi so should take twice that before bursting. I'm not sure what sort of pressure a Cruisers brake system could get to under sudden heavy braking but it could overstress it in theory. Bundy tube is better which is copper coated steel and more like the right stuff. Cheaper too.

But they sell copper pipe specifically for braking systems surely. I've just been on Wikki, and it suggests between 1200 and 2000 psi... both well over double the rating you mentioned Rich.

I'm sure the copper brake pipe will have a higher psi rating, thicker walled perhaps?

 

[StarCruiser]

Is it copper or copper clad steel (bundy tube) Clive? I've no doubt the copper would take far more pressure than what I've stated. It normally runs at that so should have a factor of safety if at least double that I would imagine. I'm probably thinking about different stuff in all honesty.

 

[clivehorridge]

Is it copper or copper clad steel (bundy tube) Clive?

What I used to use was all copper, and what I have hanging in my shed here is also 100% copper, sold to me as brake pipe, from a motor factor.

It's much thicker walled than normal larger bore copper plumbing tubing.

I don't know what the fridge tubing is like, at all.

 

[StarCruiser]

I can't see a problem with that Clive. I wonder what the reasons were for the objections.

 

[Firewout]

Anyone ever worked with cunifer brake lines? They should be stronger than copper and more corrosion resistant. It's an alloy of copper nickel and steel.
A bit harder to flare than copper.
https://www.frost-auto.nl/remmen-en-vering/cunifer-remleiding-3-16-4-76-mm-

 

[Gary820]

I prefer the Kunifer brake pipe, it's a bit harder to bend and keeps shape better when fitting, stays looking nice for longer.
I like neat brake pipes and was known at BMW for very neat pipes.

Don't have an issue with copper and many people use it without a problem, I've used it before if it's all that's available.

 

[clivehorridge]

I can't see a problem with that Clive. I wonder what the reasons were for the objections.

My thoughts were too many DIY ers not offering enough clamping and supports. Steel pipe has much more integral strength and is less prone to cracking, but I always took extra care over that aspect.

There used to be a variety of tubing available, but I forget the different names. One was like cuniper an alloy / mixture of zinc and copper, and several others using steel alloys.

PS Gary beat me to it...

 

[StarCruiser]

Seems like that's absolute then really. Copper is fine if fitted correctly and well supported.

As an aside, Isn't Cunifer an alloy of copper, nickel and iron Clive? I really don't know but guessed by the name being Cu Ni Fer… I may need to Google.

Ok just Googled, seems it's a cupronickel alloy either 70/30 or 90/10 but can't see where the Fer bit comes from.

 

[frank rabbets]

Does'nt the pipe need to be specified as "brake pipe". Using a non specified pipe which just happens to fit is not a good idea. It's a bit like using an olive for a joint instead of a flare. I've seen that on an Aston Martin which had been repaired !!

I've always used "Cunifer". It work hardens so it's best to get any bends right first time especially with the large 5/16" diameter reservoir supply pipes if you come across those.

 

[clivehorridge]

Does'nt the pipe need to be specified as "brake pipe". Using a non specified pipe which just happens to fit is not a good idea. It's a bit like using an olive for a joint instead of a flare. I've seen that on an Aston Martin which had been repaired !!

I've always used "Cunifer". It work hardens so it's best to get any bends right first time especially with the large 5/16" diameter reservoir supply pipes if you come across those.

I've never used anything other than designated brake pipe, but there was always the more expensive option of pure copper.

However, I'm going back a bit in history, circa 1980's, so times may have changed (as they do) and pure copper may be in disfavour now, for all I know.

 

[Gary Stockton]

My 80 got its first advisory at MOt last week for brake pipe corrosion. Looked at copper, spoke to Jon and I'll be replacing with Kunifer as it is better than copper imho. No work-hardening issues and I'd hate to damage copper pipe when away somewhere. Got some on order now along with pipe flaring tool. Still got to count up how many terminators / joiners etc I need as I'll be replacing the LSPV at the same time as well as the flexi hoses.... Looking forward to taking a week off and enjoying myself lol

 

[Shayne]

If i used copper i would polish it to a shine , it sounds daft i'm sure but it keeps corrosion at bay for a very long time .

 

[Towpack]

The green sulphate compound that appears on copper exposed to the elements is what prevents, or at least, slows down corrosion. This usually forms very quickly on unpainted copper. Must admit that polished copper piping looks the biz though.

 

[flint]

Ok just Googled, seems it's a cupronickel alloy either 70/30 or 90/10 but can't see where the Fer bit comes from.

Found this: The copper-nickel alloy used for brake tubing typically contains 10% nickel, with iron and manganese additions of 1.4% and 0.8% respectively....... so it should really be Cunifermn

Copper brake pipes are banned in quite a few countries, work hardening can be a problem (on flares, bends etc.). Cunifer is the way to go.

 

[frank rabbets]

Cunifer defo work hardens in as much as if you bend it and then try to straighten it to reform the bend it is more difficult. I am not saying it would work harden in use then fail.
Every 12 months I go round all the original 80 brake pipes and hose ends with EP 90 from a large syringe and they are still in very good condition.

I've spliced many a pipe on cars to avoid having to replace the whole pipe. I dont think there is a bimetallic corrosion risk of doing so. Quite acceptable to my MOT man at least.

 

[Shayne]

The green sulphate compound that appears on copper exposed to the elements is what prevents, or at least, slows down corrosion. This usually forms very quickly on unpainted copper. Must admit that polished copper piping looks the biz though.

It's probably different copper but because i hope few others get forbidden to stand at all for months on end as i was 12 to 15 years ago i can tell you that i bum shuffled around the house and polished every radiator pipe just once to beat boredom .
Pipes are now the dull brown copper you might expect but there's very few spots of green to be seen . Polishing seals them is my take on it .

 

[Andy]

So what size pipe & threads are on an 80? i seemto remember that when I last looked at brake pipes there were all different sizes available?

Andy