Re: Knob repair tips

Chuck Harris
 

I wouldn't, as you really have to be gentle here.

Even the elastic bands, if too tight, will leave
a depression when the knob is in the molten state.

You want the bands stretched a bit, but not even
close to tight.

You should have some compressed air to cool the center
on hand, as the hub can retain heat a lot longer than
you might think. A water dunk would be ok, if the
set screw is removed afterwards, and the knob let to
dry thoroughly.

-Chuck Harris

Tim Phillips wrote:

from Tim P (UK)
................ or use an adjustable hose-clamp ('Jubilee clip') to hold
the bits onto the hub ?

Tim




On Thu, 7 Nov 2019 at 12:36, Chuck Harris <cfharris@...> wrote:

Because the plastic has shrunk, you need to increase
the space for the center hub. The easiest way I have
found is to assemble the parts as well as you can, and
then wrap some rubber bands around the knob to provide
tension.

Then take a soldering iron, and heat the center hub.

The instant the plastic relaxes, remove the heat, and
cool the hub by blowing on it.

After all is done, a drop of acrylic solvent glue will,
seal the deal, so to speak.

-Chuck Harris

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