Is there any solvent which can remove dried model glue ie testors humbrol liquid glue? Begging the question how do you get rid of excess glue on models?

AFAIK, anything that will dissolve liquid model glue, will also dissolve the plastic. You can try the liquid that s sold for de-bonding super glue. That I have used, and if you are very careful, it won't damage the plastic too much. But it will discolor the plastic.
Or you can sand the excess glue off, if it over ran the surronding area.
HTH

Place the parts in a plastic zip lock style bag and spray with a liberal amount of oven cleaner. Let this set for a few hours. This will loosen the glue and also remove any paint that may be on the parts. Be careful though. If left too long (many days) some plastics become brittle and break easily.

Darn, Gino,
That's a good idea. I have heard of oven cleaner to remove paint. But I didn't realize it would soften modeling glue also. Thanks!

Gino,
I find it hard to trust chemicals like oven cleaner when it comes to a fine model, but as a last resort, I'm sure it's worth a try !
Thanks for the hint

Jan

They make glue off type stuff I thin, but I am not sure how it works, there is some stuff here in the States called like goop be gone or goof off or something like that that can get rid of glue, and I think nail polish remover does, but they may have taken out the ingredient in it that does that.

P.S. If it takes off glue, it is possible it will take of paint and perhaps even the plastic with it, just a word of advice.