Making a large tap for wood threading
I have a desire to make large threaded wooden bench screws and the associated nuts. I'm thinking 2 1/2" to 3" in the range of 2 to 3 tpi.
I can buy them ready made from Dieter Schmid at Fine Tools but I don't want to spend €1126!
I could just buy them I suppose but that really wouldn't be enough challenge! :)
I can make a screw box but I still need a tap. I'm thinking it should be possible to have one made for somewhat less than €1126 but I could be wrong.
Another possibility I suppose would be to start with a large bolt but I would still need some turning done on it to make a tap.
Anyone got any thoughts?