Here is a neat trick shown to me by Larry Moskiewicz.
The purpose is to make sure that the wooden strap cutter does not wander off too easily when you cut straps for horse tack or belts or any other strapping.
By gluing a 1/4" wide strip of cardboard into the tool, the bar holding the blade is swung slightly, which gives the blade a very slight angle to the cutting direction so that it ever so slightly forces the leather strap being cut, against the guide handle.
I think the photos explain themselves well, but I will show you a close-up or two:
Here you can see the edge of the piece of card board - it is just about 1/16" thick and 1/4" wide.
From another angle you can see the piece of cardboard just about showing behind the bar holding the blade.
The next photo shows the same angle, but the bar holding the blade has been drawn back into the handle to expose the piece of cardboard.
This small modification makes one of the simplest tools to use, even more effective than it already is.
