Cutting and Trimming Aluminum and Plastic

Advice on bits and blades that work will with aluminum laminate and plastic resin material. October 2, 2007

Just looking for recommendations on a good saw blade for cutting aluminum laminate with no phenolic backer, and recommendations for flush trim and bevel router bits that work well for aluminum. I also have some 3/16" resin panels to cut and am looking for suggestions on a good saw blade that won't melt the edges of the resin panels.

Forum Responses
(Cabinetmaking Forum)
From contributor L:
Cutting thin aluminum can be done well with a high tooth count blade with an alternate top grind on your table saw. The use of a zero clearance insert will help support the material during the cut and minimize roll under and burring the pieces. If you cut thicker aluminum, you may want to switch to a triple chip grind on the blade.

For cutting the resin panels without melting the edges, try not to use a blade with too many teeth, as most people do. Try to use a blade with 60 or 80 teeth over a blade with 100 teeth on thin materials. The other alternative is to buy either a thin kerf saw blade made for plastics or a No Melt style blade that many companies offer.

As for router bits, you can use any good industrial router bits. You may want to reduce the RPM's and feed rates, though. There are some special flush trim router bits that use a spiral flute that may help with cutting aluminum laminate. The aluminum laminate is going to put a notch in the carbide quickly, so change the height of your bit a little every so often to get the most use out of your bits. Especially since you will probably not get any sharpenings out of them due to the notches in the cutting edges.

From contributor B:
Try turning your carbide blade backward.

From contributor T:

I hate to contradict anyone, but you should never run any blade backwards. In fact, due to the clearance ground into carbide tipped saw blades, they have no cutting action at all when run backwards. A blade run backward will only rub and burn its way through the cut, which will cause more melting than a blade run the right way.

The other reason not to run a blade backwards is the damage you will most likely do to the blade or yourself. The teeth in the blade can break or be pulled out of their seats and loose teeth mean flying parts. The right blade for the job is always cheaper than injury to yourself or an employee.

From contributor B:
I don't cut much metal and if I do, I have a band saw or Roto-Zip for that. The reason I posted what I did is, I have a neighbor who put a metal roof on his shop and when I asked him how he cut the material, he said an old timer told him to turn the blade backwards. It did do a great job. He had many cuts that were not just straight. As you say, better to have the right tool and be safe than sorry.