Caught a rather large marten yesterday and am figuring my marten boards might be to small. Should I put him on a fisher board or double up or more on my belly wedges?

With out knowing the size of the marten and the boards that is hard to answer.

I don't know how to post pictures but he's pretty big around. I'll see what he fits best on I suppose.

I'd like to see That!

Biggest one I've ever caught which probably don't say much. Lol. Can't put my hand around him unless I squeeze the (This word is unacceptable on Trapperman) out of it.

Might consider making another board. But I would try to get as much length as possible without distorting the proportions. I think the longest one I ever caught went a bit over 27 inches on a standard board

Had to extend a 36" board with cardboard once so I could tack out the tail, thought I caught a fisher at first.

If you have a cell phone send the pics to someone to post for you.

My male boards are 4 1/2 " at 36". Maybe your marten boards are too skinny for a big marten.? It appears the fisher board spec'ed out by FHA is not that much wider at 36"