Ed Pawlowski wrote:
"MiamiCuse" wrote in message
...
I have a few brass cleanout plugs on cast iron risers, they
probably have not been opened in 30 years and would not come out. I
tried a 18" wrench and even a chisel with a hammer to try to
drift it open and it would not move an inch. Soaked with WD-40 let
sit for an hour tried again no luck. I think my only option left is a
desctructive method.

Can I drill a hole and start a cut with sawzall to cut a piece out
(like a slice of cake)? and then use a plier to pull it out once a
slice is removed? I don't care about the plug I can replace it
with PVC plugs, but I don't want to destroy the threads (or
whatever threads are left). MC

The threads may already be shot. I'd try heat next. Lots of heat.

After you get it real hot, squirt some penetrating oil on the seam. The
chilling effect of putting the penetrating oil on the hot metal causes it to
suck the oil into the threads. Did this many times in my fathers auto repair
shop to get rusted parts apart without damage. Then heat again and use a BIG
wrench, possibly with a pipe a few feet long on the end of it. If that fails
destroy it and replace it.