DaveSSS 

I only use JB Weld epoxy, preferably in the large 10 ounce size tubes that has a tensile strength of 5000 psi. I made a up mock-up of an extension today, but didn't waste the expensive JB Weld epoxy on it. I used some body filler that I had laying around. One thing I found was that my steerer was .002-.003 inch under 1.125 inch in diameter, which made the fit of the copper coupling a little too loose to insure the best alignment. I fixed that with one wrap of cellophane tape around the steerer, to make it larger. A snug fit of the coupling is a must. Body filler should never be used for the real thing - it's both weak and suffers some shrinkage in curing. Good epoxy won't shrink when cured.

Jonneh

Dave, would you mind reposting the image of your epoxy compression plug? With your approval of my MS Paint mock-up, I think I have the right metal image, but just out of interest...

Also, regarding the foam rubber, I have some of the pale yellow stuff (resembling mattress foam). It's fairly dense, and the pore size isn't overly large. Will it do to prevent leakage of the epoxy while it cures?

DaveSSS 

My picture still shows on my tablet. Any foam rubber will work, as long as the plug is larger than the steerer ID.

Jonneh

Oh. Not on my phone or either of two browsers on my PC. Never mind.

Good to know re the foam.

Jonneh

Just to follow up on this, I went ahead with the mod, all went well, and the steerer has done some 4,000 miles since its surgery.

The technique's a keeper. Thanks DaveSSS for the walkthrough.