Get a reciprocating blade desingen for cast iron!!
"HeyBub" wrote in message
m...
MiamiCuse wrote:
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.


If all else fails, try:

* Thermite
* Primacord