I have a little Scotchman ironworker. It shears structural steel stock fine, but it hasn't ever worked on sheet metal (gap too big). Today I removed the lower bar shear blade, cleaned it, cleaned behind it, and shimmed it out to close up the gap. Now it will cut sheet metal, except in the middle. There is apparently a wear spot in the middle, because when the blades are closed the gap in the center is about .005" larger than elsewhere. It would make sense, because that's where most of the flat bar gets sheared.
Seems like I could grind the vertical face of the blades until they clean up, adding shims to replace the material ground off. I hate to think of what a new pair of shear blades would cost from Scotchman!
I'm wondering if my plan will work. Anyone else try this? It wouldn't just be an issue with an ironworker shear, could be about any guillotine or scissor type shear.
If this does work, then I'm going to have to find someone with a bigger surface grinder than I have, mine's only 12" and the blades are 14" long.
Grant Erwin Kirkland, Washington