On Thu, 24 May 2007 08:28:58 +0100, "Simon"
wrote:

I've got an old patio door that is very hard to slide backwards and
forwards. It runs on 2 pairs of 30mm plastic wheels, running on a steel
rail. At least one of the wheels is disintegrating, and it looks like I
would have to partially dismantle the door in order to remove the wheel
bogie.

Rather than hunting around for a compatible replacement bogie and then
taking the door apart to fit it, I was thinking of buying a nice big block
of PTFE from RS, and fixing a bit of it to the bottom of the door, with a
channel cut in it to keep it on the rail.

Has anybody tried this? Would this have low-enough friction? Would bits of
grit get stuck in the PTFE and then abrade the steel rail?Presumably there's
a reason that patio doors use wheels rather than blocks of PTFE?

Thanks.

I have used PTFE for sliders and it was a waste of time. The stuff
scratches easily and when rough, is not very slippy.

What you want is someone who does small lathe work, and get them to
make some new wheels for you.