If you do not want to grind a blade, you could use a Xacto number 17 blade with only the corners rounded to prevent gouging in the surrounding area during carving; however, I believe a much better solution is to buy the micro knife handle #81067 and surgical blades #61, #81084 and #62, #81085 sold by MicroMark. I use these micro handles and blades to do final cleanup of carved off areas after using the Xacto blade.
No matter which knife or blade type you choose, you should keep the blade sharp to remove the molded on grab irons or ladder rungs easily. After several projects or before, the knife blade of choice will dull. Of course, you can get rid of the old blade and replace it with a new one. If you have ground a blade like I have, you may as I choose to sharpen it rather than grind a new one. To sharpen a blade, I use a fish hook sharpening stone and a piece of leather. On the stone, only a few strokes are needed to sharpen a dull blade. Next I strop it on the leather piece to obtain a finer edge.
With the tools describe here, some time and patience, you will have molded on grab irons and ladder rungs removed from a freight car ready for paint touch up followed by drilling required holes for the install of wire grab irons and ladder rungs.
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