Safety concern: beware of cordless drills with brakes

[ToddF]

I was looking for the right spot to post this, and was surprised not to find a safety forum.

I have seen a bunch of videos on youtube of people running shooter wheels with drills. We tried this last night with a fairly new Dewalt cordless drill. It incorporates a brake which is intended to slow down the chuck when the trigger is released. This brake kicks in as soon as pressure to the trigger is lessened and the speed begins to reduce. Since we were driving a shooting wheel with fairly high momentum, the wheel tried to keep coasting. This interacted very badly with something in the chuck brake mechanism, and caused the brake to instantaneously lock. The momentum of the spinning wheel caused the drill to kick violently, and nearly ripped the drill out of the hands of the student using it.

I have never seen a drill behave this way, and wanted to warn the community before someone gets hurt. We switched over to driving the wheel with a plug-in drill, with no chuck brake, and had no more problems. I don't know if this is a characteristic of all drills with chuck brakes, or just this particular Dewalt model. But, if you choose to run your prototype shooter with a drill, be on your guard.