s3 brake line material

[simon a-b]

Hi all

My S3 has failed an inspection on the basis that the inspector thinks the brake lines are copper. My understanding is that they are Cunifer/Kunifer depending on your spelling preference, and were never installed as plain copper. 

Is that right? It's a UK spec car, even though it's now resident in the apple isle, Tasmania Australia (home of some of the best twisties!)

The inspector suggested that the lines may have been changed at some time- I can't find any mention of that in the history I have (which is not comprehensive but quite good). 

So- how do you identify the difference between copper and cunifer- is there a way to do this?

And- did they ever build with copper lines? If so which years/models?

Thanks!

Simon

[Barrykearley]

Kunifer and copper are slightly different colours.

bottom one is copper. It’s nowhere near as resilient as kunifer. If it is copper - In many places it is indeed not allowed to be used - and for good reason - get them replaced.

[andydclements]

Originally they'd have been steel as far as I know, which then would have deteriorated and been replaced. As Barry says, copper is bad, it breaks (you may think copper is flexible, but it doesn't stay that way) and needs a lot more bracing points to stop the fracturing/ sagging etc. In terms of materials, it's not a high cost to do a complete system replacement yourself.

[simon a-b]

Thanks for the replies... of course if it is copper it'll get replaced. They like to replace with a steel alloy tube here, with good corrosion resistance. The inspector that failed the car runs a specialist garage that can do the work. Estimate is a fairly reasonable $700, and spending the money with the local inspector/guru buys more than just the job getting done. 

I'm not convinced that it is copper though- from the reading I've done british cars like Lotus were using Kunifer from sometime in the 70s, so I would have thought it would be that material from new. Can anyone confirm what material was originally used? If they were originally steel then it's more possible that the replacement was copper, as it's definitely not steel now!

What I need is a way of determining accurately what the existing lines are made of... 

The inspector guy also said that Kunifer would have a number or marking on it somewhere, which he couldn't find. Anyone seen anything like that on their cars? 

He also failed me on not having rubber covers on the pedals! I'll put in an order for some from SJ. Apart from those two he was happy with the car...

Thanks,

Simon

 

[andydclements]

I've cut off lots of steel pipes S3 Esprit, Turbo Esprit, Excel, and I doubt any of those were after-market, so I'm sure they were coated steel as new.

[CarBuff]

2 hours ago, simon a-b said:

He also failed me on not having rubber covers on the pedals!

If you mean the rubber pedal pads,

 

JAE Parts in the USA had replacements made up for the brake & clutch.

 

The accelerator pedal was always plain metal.

[drdoom]

I've got the original brake pipes in the garage, they certainly were not steel. Appear to be Kunifer, having slightly less orange hue than copper. Lotus at no point in the Esprit program were indifferent to liability concerns as the US market was always key to its prosperity. Will take another look this morning, perhaps a photo to post here.

[simon a-b]

11 hours ago, CarBuff said:

If you mean the rubber pedal pads,

 

JAE Parts in the USA had replacements made up for the brake & clutch.

 

The accelerator pedal was always plain metal.

That's what I need. SJ Sportscars (UK, good website) has them for all pedals- I think some in a 'Lotus' box even! and not too much so I'll get them from him I think.

Simon

It's not surprising I think that there are different experiences/opinions considering the 'parts bin' methodology. Is it possible that OS delivery spec cars were Kunifer and local cars were steel? If you've seen/removed steel brake lines when doing restoration I think that's fairly conclusive that there were cars with steel pipes from new. 

Is there a test I can do to find out the truth? is the Ni/Fe component in Kunifer enough to make it noticeably ferromagnetic? If a rare earth magnet will stick to Kunifer but not to copper could that be a possible check?

 

 

[simon a-b]

8 hours ago, drdoom said:

I've got the original brake pipes in the garage, they certainly were not steel. Appear to be Kunifer, having slightly less orange hue than copper. Lotus at no point in the Esprit program were indifferent to liability concerns as the US market was always key to its prosperity. Will take another look this morning, perhaps a photo to post here.

Thanks Steve. Can you see if a strong magnet will stick?

Cheers,

Simon

[drdoom]

Will do. Done for today but at it tomorrow.

[drdoom]

Just offered up a potent neodymium magnet to one of the main brake pipes, utterly ineffective therefore certainly not substantially ferrous. To reiterate I am certain to have removed what were the original pipes fitted at factory. Altogether inclined to think they are Kunifer, and I've seen plenty of true copper pipe in my time.

Cheers

[simon a-b]

3 hours ago, drdoom said:

Just offered up a potent neodymium magnet to one of the main brake pipes, utterly ineffective therefore certainly not substantially ferrous. To reiterate I am certain to have removed what were the original pipes fitted at factory. Altogether inclined to think they are Kunifer, and I've seen plenty of true copper pipe in my time.

Cheers

Thanks Steve, and you're sure when you replaced your lines you put Kunifer in?

If so the magnet test is a bust. 

Cheers,

Simon

 

[drdoom]

I offered up the magnet to a pipe which was a remnant of the restoration teardown, therefore known to be original. I have a lovely coil of Kunifer set aside for the fabrication of new lines, sometime this year.

[simon a-b]

7 hours ago, drdoom said:

I offered up the magnet to a pipe which was a remnant of the restoration teardown, therefore known to be original. I have a lovely coil of Kunifer set aside for the fabrication of new lines, sometime this year.

Did you try the magnet on the known Kunifer you have in stock?

[drdoom]

The brand new Kunifer is utterly indifferent to a neodymium magnet. Note the package details, looks to be 90% CU, 10% NI. No ferrous content, as I had figured.

Cheers

[simon a-b]

16 hours ago, drdoom said:

The brand new Kunifer is utterly indifferent to a neodymium magnet. Note the package details, looks to be 90% CU, 10% NI. No ferrous content, as I had figured.

Cheers

Thanks Steve. New lines will look great once they're done!

Cheers,

Simon

[simon a-b]

A small update- I contacted a Cunifer company and asked them the question. Here's the response:

 

Hi,

 Simply polish it up till it's shiny, if it's Cunifer it will have a golden lustre like 14 carat. Copper has a distinctive red color.

 

 Also, in spite of what you may read on the internet, it is mildly magnetic due to the 1% iron content. You would need a powerful magnet but you'll be able to tell that it is indeed magnetic:)

 

HTH

Thank-you,

Tim Beachboard

Federal Hill Trading Company

195 Federal Hill Road

Oxford, MA  01540

Phone:  508-987-2660

Fax:  508-987-2661

www.fedhillusa.com

www.cunifer.com

 

So thanks Barry for your early response on colour- seems like it's the only sure way. 

 

I've kept their details in so anyone else can make contact if they want- I have no connection to the company, other than thanking them for responding.

 

Interesting that he says that Cunifer, ie not just CuNi, but with a bit of Fe in it is mildly magnetic. 

 

I'll do the polish it up test, and compare to a bit of polished up copper pipe (just old water pipe, but AFAIK that's just Cu). And if I think its Cunifer, possibly original, and possibly therefore with the Fe content I'll try some strong magnets. 

[simon a-b]

Update on my brake lines. My lines are mildly magnetic! Enought for a strong rare earth magnet to cling to them. So I think this is probably enough proof that the lines are Cunifer for my inspector, along with the email above. 

I also gave it a bit of a polish- to see if it looked more yellow than copper water pipe, also polished. Not conclusive, but the magnet test is all I need I hope.

Cheers,

Simon

[SciroccoEV]

The factory brake hardlines on my '85 Excel are definitely Copper. Far too soft to be a Copper Nickle alloy (ie Kunifer).

The downside of copper is work hardening and becomming brittle, but if it's well mounted and not flapping about it shouldn't be  problem.

[simon a-b]

Copper would not pass inspection in Aus- at least not the inspection I had for rego as a special vehicle- a kind of enthusiast category with limited use but reduced rego costs. They would require it being removed as happened to me...

That's not to say it's not safe, that's a different question!