no one told me. this is why you aren't supposed to cut metal with a mitre saw. my little dust blowing bag caught on fire when i was cutting pipes. i went to home depot to buy another bag and the guy made a horrible face when i told him why. (they don't have bags btw). he informed me i need a metal chop saw. he said i will ruin the motor of my mitre saw as all that metal shrapnel that i see flying all over the place is going right into the motor. a chop saw motor is encased and protected from such debris. at this point i have cut enough metal with this saw that i guess it is a lost cause, already i have noticed so much grit gets into it that i can barely use the gauges to turn it at angles. just another thing to learn. another thing to buy. another 20 or 30 taxi rides away.