Cutting 4" holes in fiberglass seat bases.
So I've found that cutting 4" holes with a hole saw is a serious PITA. My 18v cordless drills get toasted in short order. I even bought a corded drill and found that I can smoke the motor on that one before I make much progress on the hole. I've got a couple more hot tubes I can add to my heater system but drilling the holes is literally a process that takes multiple sessions of drilling over a day or days. It doesn't seem like it should be this hard.
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What am I missing or doing wrong?