View Full Version : turning CastIron

11-06-2003, 12:13 PM
greets all..
have to turn an M30X3.5 internal thread
on a biggish cast iron pulley.

haven't done alot of cast iron turning..
and have *never* turned a thread in it.

any tips to save a fella time/trouble?
what sort of cutting fluid should i use,
if any?

the internal thread is about 5cm long, down
in a 10cm hole.. so i wont be able to see
whats going on.. (its a through hole, not blind).. i plan on turning the thread real slow. any problems with working cast iron slow? i'd hate to have a thread break on me and ruin the piece.


11-06-2003, 12:23 PM
No cutting fluid needed.

11-06-2003, 05:46 PM
Dry...cast iron dust + liquid makes a gawdawful mess.

That's a pretty hefty thread. It shouldn't be a problem. Just be sure to get enough relief on the "heel" of the threading tool so it doesn't rub. I've had trouble on occasion turning large coarse threads when I didn't pay enough attention to that detail.

Forrest Addy
11-06-2003, 06:21 PM
Machine it dry with neutral rake tools. Suck up the chips with a shop vac. Bada-bing!

11-07-2003, 02:51 PM
hey thanks for the tips.
the thread turned out great.. nice
and clean. i was surprised at how
well cast iron cut. relatively soft,
i would say. all that dust probably
isnt very good for my lathe, however.

tried to clean up as best i could.

took longer to make the HSS toolbit for
inside (left hand!) threading! probably
spent 3hours and 1wheel on the grinder, and
30minutes cutting the thread.

all that for $30. but, somehow, it was fun.

this sure is a twisted hobby.

thanks again,

11-07-2003, 06:33 PM
Save the dust-chips... get a large campfire going.. and .... YOU TOO can be a magician.. POOF...

z(works for brake dust anyways) I am not real sure how safe this is, was, since I was intoxicated the last time..