Need a better way to cut Aluminum plate

[David Bally]

I have had good luck cutting alumimun with a table saw or skill saw as has my uncle, see 1/3 B-17. He has cut 4" blocks on a table saw by cutting half way from each side. To slow the saw down to help control heat build up, use the next size smaller blade, i.e. a 8" or 9" in a 10" saw. A good carbide blade works if you do not build up heat as this will chip the carbide, not a problem on thin materials. Boat builders use saws for cutting aluminum. As for routing, there was a EAA Hints for Homebuilders segment showing the process in which they cut wing ribs. Use gloves, long sleeves, hearing and face protection as the chips are hot. You may have to promise the wife you will replace the carpet if you track those sharp chips into the house.

[Tex Sonex]

Don't know what you might have near you. I used to work for a major airline and we had a monstrous shear that would cut 1/4 inch aluminum- and full sheets at that. It would take up to 12 feet of width. Of course, it shook the ground when it made the cut. Like someone said- hire it out, especially if you could find access to such a machine.

[Rotornut]

Seconding above recommendations. I mentor a high-school robotics team, and we're in "build season" right now. The machines are mostly aluminum. We use a miter saw with a carbide-toothed 10" blade. I built a fence to push the stock against and hold it square (bolted to the table). Added toggle clamps, rubber tips that are adjustable for thickness, to hold it down. We can do a 10" long cut.

We also have a local waterjet company cut complex shapes. It's fast and nice, and looks great. It even cut our .201 holes for screw clearance.

[Eric Witherspoon]

How long? How straight? I have used table saw, band saw, and chop/cutoff saw, as well as router on Al. Length of cut + amount of post-cut finishing usually drives my decision process. Table saw I have found leaves an "almost ready to use" cut, in that the steadiness of feeding the material through the saw can result in circular marks, slightly in/out of the plane of the cut (result of the blade going around). Router, I have found loads up and recasts material on the cut zone - basically a router runs way too fast for clean Al cutting. Band saw, I run these parts back over a belt sander then Scotchbrite wheel to get a buttery-smooth edge - so a good bit of work, and usually reserved for smaller gussets and the like. A big shear sounds promising, though it sounded like you want something you can do yourself. A cutoff wheel - would be quite difficult to get good straightness over any length.

[nrpetersen]

Router, I have found loads up and recasts material on the cut zone - basically a router runs way too fast for clean Al cutting. ...............

Try putting a line dab of sulfur cutting oil in top of the aluminum to minimize built-up edge. It doesn't eliminate it but it sure helps - depending on the alloy being cut.

[Bill Berson]

A cutoff wheel - would be quite difficult to get good straightness over any length.

How about a thin kerf, 4" cut-off wheel in a tablesaw?

I just tried my 4" cut-off wheel (mini-grinder) on aluminum. It worked better than I thought. Did not load up, or kick back dangerously like a carbide saw. Probably wear quickly, but they are cheap for a ten pack.

[BobMo]

Just to update..I bought a carbide 10"x 60 blade and it worked great. Good for about 9" then the blade hit the aluminum on the upstroke in the rear. Still, it worked far better than my band saw on straight cuts. Thanks for all the tips. Especially the aluminum chips in the carpet warning.

Bob MO

[Piet]

Bob most likely your fence is not quite parallel with the blade. My fence has adjusting screw on the end with the locking handle. Rip a piece of scrap wood and watch ate the teeth coming up out of the wood. If it is coming from the right side of the saw adjust the fence to the right and vice versa.