On 1/11/2014 7:21 PM, Jon Danniken wrote:
On 01/11/2014 11:44 AM, Kay wrote:

I went through my mastercraft bimetal hole saw on my steel door
Then a 15$ one from princess auto then the most expensive one I could find
21$ and still all I get it a but of sparks, some smoke, and my paint
around the hole is turning brown.

You're probably not applying enough pressure to actually cut the metal,
but instead running the saw on the metal creating friction, as evidenced
by your paint burning up. You need to put your weight into the drill so
that the teeth can do their job, and not spin the drill too fast when
you do this.

For jobs like this I use a 1/2" chuck drill, because it turns slower
than my regular 3/8" chuck drill.

I can't speak to the quality of mastercraft bimetal hole saws, but I do
know that Lennox makes a reliable one.

Jon


Is the rotation of the drill motor correct?