Hi Ed,
Not sure, but I think you are saying that pure copper is still being
sold for brake lines. Since some cars had this material originally, it
may be that some are willing to accept it's shortcomings in the interest
of originality. Copper just has too many failures due to work hardening/
fatigue cracking to be safe for fuel or brake lines. Most of the brake
line failures are right at the flare junction which is subject to
considerable pressure expansion stress cycling. I discovered this 50
years ago, as did the US auto industry.
We may be missing the fact that many people have gotten away with using
copper. It does usually require long usage before failure, but there is
no way to know ahead of time when it is about to fail. This doesn't mean
that it is a safe thing to do. The failure will be sudden. I do not know
of any USA racing orginizations that allow copper & no present car
manufacturers use it for the stated reason.
The UK industries have not been particularly noted for updating things
that don't work well. Especially the small industries.
Dave Russell
M.E. & E.A. Driver wrote:
> Hi Dave
>
> This thread peaked my curiosity. Like you and John I'm in favour
> of the soft steel brake line but I note with interest in two of many
> catalogues I have from the UK that copper tubing 3/16 to 5/16's
> plus the nickel/copper alloy are still being sold for Morgans by a Morgan
> outlet while in a generalist catalogue the same is offered. I wonder
> if we are missing something?
>
> Kind regards
> Ed
> Saskatoon, Saskatchewan
> www.vintage-sportscar-touring.ca
> '65 BJ8 '89 Morgan 4/4
>
>
> Dave & Marlene wrote:
>
>> John,
>>
>> Several materials have been / are being used for brake piping.
>> First & worst is regular copper. Copper work hardens with vibration &
>> flexing & fatigue cracks. Not good for brake or fuel lines.
>>
>> Low carbon annealed steel has been used for many years. It is not
>> subject to fatigue failure but has rust & corrosion problems.
>>
>> Various coatings have been used to protect the steel, such as, copper
>> & tin plating. A typical brand is "Bundy"
>>
>> A 90% copper - 10% nickel alloy (UNS C70600) has been used in Europe
>> for many years. It has the fatigue resistant qualities of steel & very
>> high corrosion resistance. I don't know whether present US car
>> manufacturers & racing organizations are sanctioning It's use or not.
>>
>> The confusion may be between copper, copper plated steel, & 90/10
>> copper - nickel. The all appear to be somewhat copper color & all
>> contain copper.
>>
>> Dave Russell
>> BN2
>>
>> John Miller wrote:
>>
>>> You're not using copper for brakes lines, are you? They *will* fail,
>>> which of course will always happen at the worst possible time.
|