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Re: Wampus Cat
Shop Improvements (continued)
Metal Bending Brake Modifications
I bought one of the Harbor Freight 30 inch sheet metal brakes a few years ago and have used it to make the upper rocker patches (see post 56 and 57 above), the A pillar drip rail replacements (see post 89 and 90 above), and a few other patch panels. However, the brake as purchased requires the use of a number of C clamps to hold the clamping bar, plus the clamping bar still slides around when bending sheet metal.
I looked around on the web for articles and videos for improving these brakes, and the one I liked best is a YouTube video “Harbor Freight sheet metal break” by 52drj. I didn’t copy this YouTube design but used it as a starting point in thinking through my modifications.
I made a brace for the top clamping bar from 1 ½” x 1/8” thick steel angle scrap that I had on hand and skip welded this to the top clamping bar. The brace runs all the way to the ends of the clamping bar for stiffness but is modified on the ends to allow clamping bolts to pass through to the top of the clamping plate. I fabricated a handle from ¼” diameter rod for use in lifting the clamping bar while inserting material.
After mocking up the part in cardboard, I fabricated the brackets on the ends from 2” square x 1/8” thick steel tubing that I had leftover from a trailer hitch modification . The upper clamping bolts on the ends are 5/8-16 Grade 5 bolts. The handles on the clamping bolts are ¼ steel rod which operate like the handles on a C Clamp.
The horizontal bolts that hold the clamping bar in place and prevent it from sliding backward are 3/8-16 Grade 5 bolts. An extra nut is added to lock the bolt in place once the upper clamping bar is in position.
When finished with the modifications, I bolted the metal brake assembly to a piece of wood using carriage bolts so that I can hang it on the wall in the shop when not in use, but the assembly can easily be clamped to my workbench when needed.
All fabrication was done with a hand-held grinder with cut-off discs, a belt sander, a drill press, and a MIG welder.
Ready for fabricating the next C10 or TR4 parts.
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