Great idea, are they styrene?
Thank you.
Yes they are. .010", although the that was a little thick to fit between the wheel faces and the backs of the sideframes/contact strips. .005" May have been a better choice but it's a bit flimsy. I made a jig so that I could resize the different trucks. For that I used .010" sheet cut about 1"x.5". Then I used .010"x maybe .125"? strip to go in between the spaces behind the truck side frame, on either side of the axel points. Once in place I put a piece of tape over to hold them in place. I used that to cut a basic template which shaped to the exact fit. It became the mast I would use to trace the remaining three.
Then the taped one could be untaped and resized for the next truck. It took very little time and will be used over and over.
Craig