Re: how to repair neoprene wet suit ?

Based on many years' experience of mending caving wetsuits, which used to
take a real hammering, your main problem is that most diving wetsuits are
double-lined ie there is lining on the outside as well. Neoprene sticks very
well, but the cloth doesn't. For single-lined ie smooth rubber on the
outside you just whack on a big patch of single-lined - lining side out, and
Bob's your uncle. For double lined, a suggestion would be to cut out a clean
hole, then glue in a piece to fit. I do recall trimming off an inch or two
of the surface lining with a scalpel then whacking on a big patch but this
is a bit tedious albeit better. You could sew as well if you can be arsed,
but for caving it was only worthwhile for high-stress patches such as knees.
I doubt this would be worth the bother for diving. We used to find our
patches in caves as they fall off other caver's suits, but you can buy
neoprene sheet from a shop.

The above approach assumes you're not too precious about the overall
appearance.

For adhesive, my best results was some kind of industrial solvent stuff with
rubber dissolved in it - no label, nor brand name; probably now banned. Evo
stick works OKish but is a glue, rather than solvent-based so doesn't
physically weld the material. Presumably whatever the dive shop sells would
have to do if you don't have a bottle of toluene (guessing as to contents of
glue) or similar.

Caving has largely moved on from wetsuits and I can afford a decent quality
one for those few trips that involve a swim, so the tedium of repairing crap
suits after every trip is now just a memory.

Cheers

Hywel