I've got the "hub" part of a cast iron drain pipe accessible in a floor
drain, and need to notch the lip, for the outlet of one of those
li'l-giant-type centrifugal pumps that I want to drop in. The side outlet
of the pump sticks out past the diameter of the pump, ergo the need for a
notch, since it's a tight cylindrical fit. The notch needs to be about 1-2"
long, mebbe 3/4" wide. Best way to cut?

Regular metal cutting (sawzall), I think, are almost out of the question, as
I've tried this on other CI drain pipe -- pert near impossible, without one
of those coke-bottle cutting grit blades, which I didn't have.. I had to
rent one of those "splitters", and even that was difficult.

Would an abrasive sawzall blade do the job efficiently? Are there diff.
types of sawzall abrasive blades?
Woud I be better off grinding it out, with a 4.5" grinder, I spose.

O/A seems to be a poor method, according to
http://www.practicalmachinist.com/vb...t-iron-195329/

The reason being left-over graphite? Somewhere in he
http://en.wikipedia.org/wiki/Oxy-fue...ng_and_cutting

Plasma, air-arc seem to be OK, but, no gots.

Idears?
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EA