What a mess, what am I doing wrong?

100LL said:
I can’t quite get the cross slide far enough away from the work to turn it the other way..
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If you had a boring bar (3/4 or 1") and could put the holder out toward you to reach across the O.D. that may work better. Leave as little sticking out as possible.
 
Cast Iron has a very hard crust on it especially if it is Sand Cast which yours is not but it still has a hard crust that you have to get under with your first cut. Also your tool is facing correctly for a facing cut but when turning the OD toward the chuck you are turning off the end of the tool which may not have the correct relief for the cut. Rotate the tool post 90 degrees counter clockwise and turn with the other tool when turning the OD.

Durabar as you are using is extruded and cut to length so you will not experience the crust on the facing cut since that was cut with a saw but it will have a hard crust on the OD. Take a deeper cut for the first cut where the point of the tool is below the hard crust.

Cast Iron does product very small almost sand like chips so button up your collar and grin and bear it.

Good luck with your project.

Dennis
 
Speed is way too fast, the wrong tool is in the tool post for that operation, and put a little more rake in the cutter. The carbide is fine. If you try to use HSS, the cast will dull it as it's as bad as a grinding wheel. What a lot of guys on here don't understand is that you don't need to consult a book to figure out surface speed and spindle speed, and any other speeds they can come up with because 1/2 the time it doesn't work anyway unless you're running a CNC machine, or all the little duckies are lining up in a row. Everybody wants that micro finish, because they think that's the only thing that's key in machining. If you drop the RPM and increase your cutting feed, you'll end up doing the same job, in the same amount of time, and with as good or a better finish, AND save your cutting tools for another job the next time you need them. You don't have to run that lathe on the spindle speed, there's a thing on it called back gear, and it's there for a reason. Give it a shot, drop that puppy into back gear and crank up that feed rate, and don't be scared. For every 100 RPM that that cutting tool is rubbing against the metal, you can be cutting metal 99 of those RPM's by moving that little lever on the gearbox to the next slot. As for the cast getting all over the place, use your safety glasses, better yet a shield, and a get face mask for your nose and throat, because your going to get it all over, and in you. That's what cast metals do.
 
100LL said:
I can’t quite get the cross slide far enough away from the work to turn it the other way given the size of this work piece ...I must admit that aloris facing turning tool does confuse me a little.
They market it like you pop it out and go the other direction and all of a sudden your facing instead of turning, but I just don’t see that. Of course I’m a beginner.
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If you can't get the cross slide back far enough to use the holder as intended, back the compound outward until it does clear; if the gibs are sufficiently tight it should not move while cutting.
 
I have the very same Aloris tool holder. It will work as you have it set-up for doing the OD. But maybe not a cut deeper than the radius on the insert. I understand your lathe size restraint problems when trying to do the OD. As has been said many times, the skin is harder, you should cut underneath it. Even Carbide can have a hard time holding up to cast iron. It can have everything from sand to ball bearings in the pour. Maybe try the cheaper brazed carbide. Those triangle ones can get pricey. And the chip breakers on them too!
 
Tyler,

I started to ask you if you needed me to rough out that slug before I sent it. Sorry. Like many said, get your RPM down to under 100. Rig you up with a boring bar that you can sharpen a piece of HSS or Carbide and insert it into the boring bar. That will allow you to turn down the OD. Your Little Rockwell should be able to take a cut about .060" deep on the side and kick the feed up to around .025" rev. This should get you under the hard skin on that material. That hard skin is about .090-.125" thick. Also, you don't baby the feed rate on cutting cast iron. Just put a broader nose on the tool bit when taking a finish cut.

Ken
 
100LL
This may help ease the frustration but i machined some cast iron a while back to make my radius tool .I went through exactly tee same as you on nearly the same curcumstances .A lot of the guys have said the cast has a very hard crust and this is just what i found when starting of on my work peice .In the end i slowed down as suggested and yes once tbrough the crust it was fine .The end finish i was happy with apart from having to clean the stuff of my lathe and out of my nose etc that dust is a real pain in the a#@%s and gets into places you would not believe .
You can see the pic of my radius tool its machined from cast as also shown in picture .

20180225_080208.jpg

20180225_080108.jpg
 
Yep Cast Iron is some nasty stuff to machine. My trade school instructor worked for a number of years in a Foundry and when he wore a white shirt by the end of the day he would have rust stains in the collar. The only thing I ever machined that is worse was carbon for EDM electrodes.

Dennis
 
Don't know if you've got enough material to play with or not but if you do could he possibly take a grinder with a flap wheel and take off the hard outer crust then put it in the lathe and tru it up and cut on the softer material under the hard outer crust ??? I know when I'm gonna cut hot rolled I either soak it in acid first or grind off the hard surface to get to the softer metal underneath and spare my cutters especially since I have a smaller lathe and mill and can't take those deep heavy cuts to get past the hard mill scale
 
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