In article
,
405 TD Estate wrote:
When tightening compression joints it always seems a bit kind-of hit
and miss and they seem to need to be VERY tight to not leak - so tight
I worry about damaging the joint or pipe.

I normally put grease on the threads which makes them easier to
tighten but of course doesn't reduce the pressure on the parts..

After fitting a radiator the screw cap had started to crack after it
was leaking a tiny bit and I tightened it some more. So I'm wondering
if I'm doing something wrong, perhaps the pipe should be pulled out a
little bit from the joint before tightening? or anything else?

You must be using enormous torque to damage a 15mm compression fitting.

If you have leaks after normal tightening, something is wrong.

Is the pipe clean, round, straight and free from bad scratches?
Is it going fully into the fitting?
Are you using good quality fittings?

A lick of Fernox LS-X silicone sealer round the olive before tightening
won't harm - but really shouldn't be needed.

--
*Honk if you love peace and quiet*

Dave Plowman London SW
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