To prevent the saw from grabbing, I use a radial arm saw and find it works much better to start with the saw in front of the part and push it back this makes it work like a conventional cut in a milling machine, I almost always clamp the aluminum. I think most chop saws can work this way also. I think the ideal saw would be a chop saw with a good system for capturing the sawdust and aluminum chips. I usually attach a shop vac to the guard on the radial arm saw. The first time I cut aluminum, chips got into the switch, big flash, popped the breaker and scared the crap out of me. Also seen chips short the prongs if the plug is not fully into the outlet on the wall.