I use my DeWalt chop saw with a metal abrasive blade to cut aluminum tube without any problems. Incidentally, I also recently cut these 1/8" thick (and approx 16x20 dimensions) aluminum inserts for my upholstery project using a 4 1/2" angle grinder with a normal abrasive cutting blade.
And as others have noted...wear eye protection. I always use a full face mask myself...I don't like collecting metal particles in my fillings.
