Recorking clutches is remarkably simple using common bottle corks once you know the technique. These corks are getting harder to find but for example the last lot I bought came from a home brew beer kit and I believe some home wine bottlers still like to use cork so appropriate corks are still around.
There are four basic steps,
1 You must use whole cork. Do not use reconstituted cork (crumbed cork glued together to make something, eg, tiles) Do not use champagne or wine corks that are made from glued up slices of cork. It doesn't matter if you use 2nd grade corks, as long as they are made from a single piece of cork.
2 The cork should be a bit bigger than the hole it is intended for. A few Albion clutches have circular drilled holes most have a hole shaped to push the cork in sideways. Whatever you have the cork must be slightly larger than the hole.
3 To insert the corks you first soak them in really hot water until they go soft. Just use an ordinary saucepan on your kitchen stove. This is a very clean operation. Heat the water up until not quite boiling, just simmering and then throw in your corks. They will float on the surface. After 10-15 minutes pick them out, squeeze to see how soft they are and if nice and squishy push them in the holes. The cork won't be hot, it never is. You can safely push the corks in with your bare fingers. Being too big the cork will press hard against the sides and not want to move.
4 When all corks are inserted put the clutch plate to one side for 24 hours to let the corks completely dry off. When dry the cork will return to how it was before you started. It will now be hard again so you can now trim off the excess with a very sharp knife and do the final flattening on a sheet of sand paper or depending on your workshop equipment, on a disk linisher or bench grinder. This is not precision engineering, getting the surface flat and parallell by eye is sufficient. The cork will compress and flatten out slightly more when the clutch is assembled.
There you go , how to select corks and recork a clutch in one easy lesson. I suggest you check it all out by drilling a 1/2" hole in a piece of thin steel and practice the technique. It really is very easy.
Cheers,