Lure craft sell one. I made one out of single edged razor blades. Here is how.
Get about 7or8 blades.
Take the covers off of them but dont throw them away(the covers I mean)
Now slack the blades like this , Blade and a single wrapper, repeat till you have a stack.
Then carefully pick them up and wrap the handles with masking tape very tight keeping all the blades even.
That is it, just use it with something that has a little give on the bottom. Just remember you will have to press very hard to cut through all tha layers.
One other thing you can adjust the space between the blades with more or less of the papers that cover them. Hope this is what you were after. Frank