Get a weld cutting thin abrasive disc for the grinder. Done in
seconds if you can get all the way around the pipe. Grit edge
Sawzall blade will work fine, but slow. Regular steel cutting
Sawzall blades won't work as you already know.

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______________________________
Keep the whole world singing . . . .
DanG (remove the sevens)




"MiamiCuse" wrote in message
...
I need to cut a 3" cast iron vent pipe to tie to a new PVC vent.

I am using a Milwaukee sawzall with a metal blade and it kept
skidding and wouldn't start the cut at the right place. I then
used a 4-1/2" angle grinder with a metal blade and cut a little
notch and now I can engage with the sawzall without skidding.

However after 15 minutes of cut I don't think I am making a
significant dent at all.

I used the same sawzall and cut through copper and EMT
electrical conduits like knife through butter. But this CI pipe
I am not making any progress.

I can't use the angle grinder there is simply not enough room
around it.

I went to HD and they recommended a "grit iron" blade. Got that
and it seems to cut a little bit, but again after 15 minutes, I
am not even 10% through the pipe. The way I am going it would
take 10 hours.

I remember seeing another blade named "ugly metal blade" I
wonder if that would be better.

Is there a better way to do this?

I know a chain cutter may be used, but I want to avoid it. Part
of the reason I am cutting this is because the lower section was
cut by a plumber who used a chain cutter but created a vertical
crack line and now I am trying to cut away all the damaged
section.

Thanks,

MC