I generally drill a hole for the radius, deburr and cut. Never cut directly on the line, just close and then file. Any snips are fine. I don’t usually use the compound snips, don’t need them for aluminum. You will get better at it due to practice.
My cut is dimensionally correct. I think I’ll offset a line .5” in and cut again, planning to use my fine more. Thank you all
Get yourself one of these for small close work. Supper easy to use and you will love them later on the panel for cutting square holes.
2 Likes
I second what Bryan said. Always drill a hole at any corner - a square corner will eventually become a stress crack. A rounded corner spreads the stress.
And, like Bryan said, when you cut leave a little extra material and use a file to put your edge exactly where you want it.
I also suggest not using a grinder or cutting wheel (Dremel) of any kind near the edge of your material where fasteners will be placed. The heat from the friction can change the temper of the aluminum. That’s not to say I’ve never done it, but I regret having done it in retrospect.
Thanks y’all!
1 Like
I used a small round needle file to put in a radius if I miscut the hole for the radius or had to move an edge. Pressing it in the direction parallel to the one you’d like to keep can get you a new radius. I used these: https://www.harborfreight.com/12-piece-precision-needle-file-set-4614.html
3 Likes
My favorite needle file is half round, half flat.
1 Like
When cutting sheet metal, I always wear a good pair of gloves for protection. I have gone to the Dr. twice for infected slivers. I prefer the yelllow dear skin gloves. Over time, they shrink to fit your hand. If OJ had been wearing dear skin gloves, he would have been found guilty. I also have a set of small files for fine work like this.
My 1/4 round bastard file has teeth on the edges. My mill file doesn’t. My small mill file has teeth on one edge. If your not watching closely, they will make hash out of your 1/8 inch hole.
Bastard files cut on both the push and the draw, mill files cut only on the push. The tiny files use bort (low grade industrial diamonds) as an abrasive, and is nondirectional in it’s cut. Bastard files are used to remove material, Mill files for finishing.
I use my files like a plane rather than a crosscut saw. (ie, saw is perpendicular to the edge, a plane is along the length of the edge) This will take off the high spots. Check frequently with a straight edge.
I find that the long snips are useful for long straight cuts and short straight cuts. The three pack snips have red handles for left hand curves, the green handles for right hand curves and the yellow handle for straight cuts. (just like position lights)
I also use my grinder, deburring/polishing wheel on the left and grinding wheel on the right. I keep a container with distilled water next to the grinder. When the piece starts to feel warm, I dip it in the water for a few seconds to control the temperature and prevent loss of temper. Same thing when using a Dremmel.
When cutting parts, 0.063" and greater, I use either the band saw, or a hand held jigsaw with a metal cutting blade.
So the process is; Cut a piece of material large, lay out the part, cut again to roughly 1/8" off the line with power tools. Use the tin snips to trim very close to the line, grind away any silver showing between the edge and the line, use the file to address any high spots.
Every time I cut, or trim a part, I debur and break (round) the corners. It’s a safety issue.
4 Likes
I agree with all, and offer my tool for small radii…chain saw files are cheap, and come in several different sizes. I think I got mune at H.F.
1 Like
Some news. I decided my cut on the rudder skin was unacceptable and bought a 14" single action snip to get a better cut rather than the serrated Milwaukee double action snips I had from before which I bought to make a dryer duct. I offset the line from my cut and made a new cut with the 14" snips and I got a lot better quality.
I also learned to nibble around bends. I will layout the cut again and make a 3rd hopefully perfect cut tonight using what I learned last night. I still have room on my rudder blank. I need a left handed snip for a section so I’m off to home depot to get one of those today.
The good news is I’m through my mental block. Thank you all for the tips. I read them all carefully.
4 Likes