Guy King wrote:
The message
from "Grumps" contains these words:

I am trying to dismantle a child's climbing frame. It is contructed
from metal tubes. It has six legs which are formed by inserting
short tubes into each other. It has been standing for 7 years, and I
cannot pull these pieces
apart (well, I have managed two). Any advice?

Graphited penetrating and easing oil. WD40 claims it's good, but it's
not a patch on the proper stuff.

Dribble it round the joint (invert the frame if needed so the oil can
trickle down into the crevices) and leave it a day.

Warming it will help, too. With concentric rings, the outer one will
always expand more than the inner as they're heated.

Question is, can I heat it without causing any discolouration? I've tried
boiling water, but not reached for the blowtorch yet. Actually, there are
plastic inserts in the end of the tubes, so a blowtorch may not be such a
good idea (although spare inserts would be supplied free).