I have a Horsebox on a 1986 Leyland Road Runner chassis, (7.5 tonner like a
modern Daf 45).

The inspection people have just failed it for having a "braze" on the air
line from the compressor to the first reservoir. I havn't had a close look
yet, but someone may have replaced a length of the original steel with
copper. My local service guy thinks it is OK and an unreasonable fail, but
obviously sees it as a rats nest job and doesn't want to touch it. I just
need to get it fixed. Pipe is about half inch. I did wonder if it was a
soldered repair, which might be more reasonable grounds for failing.

One difficulty is access to the compressor joint (luton stops the cab from
tipping). System pressure is about 6 bar. Can't use polymer (like trailer
curlies) under the chassis apparently. Does anyone know what materials are
permitted, e.g. copper, stainless, other alloys, instead of steel? Obviously
it has to have a suitable pressure rating, presumably 12 bar or higher.
There is already one compression joint in the line (apart from at the ends).
So one strategy might be to cut forward of the braze, remove the brazed
section to the compression joint, and make up a new piece from the old
compression joint and use a second joint to connect it to the line to the
compressor. But that assumes the existing front (copper?) is actually OK. I
know about galvanic corrosion with mixed materials.

There's a local branch of Pirtek, and I'm told they can make up just about
anything, but I'm not sure if they will know for sure the legal requirements
for lorry air lines. I havn't spoken to the local DAF agent yet, but I
imagine it's not a stocked spare, so they'd just get a special made anyway.

TIA
Steve