Another Parting off Thread

how about using a bandsaw then just a facing cut
 
3/16 parting blade is too wide for a less than rigid setup. What lathe do you have?
 
Try checking your blade against the square face of the piece to be parted after checking it on the chuck to verify. I went to 350 rpm, and my slowest cross feed. The chips are curls, and I use a squirt bottle for constant oiling. My blade is 1/2" x .062 made in China. I do have a very good quality blade that I may start using once I'm confident enough. You just have to see what works for you. I am a complete novice, but I am starting to make washers now.
 
petertha said:
Minimized stick out - Parting off 1 1/4" stock - 1 3/8 Sickout.

- When you say stick-out I hope you mean the length of stock outside the jaws right? (as opposed to parting tool stickout). To make it simple, pre-extend the blade only just enough so it will go over center. Any more extension is unnecessary flex.

- How are you establishing the the center of the cutter is on center with the stock? Newby alert if its the typical blade holder that holds the blade at a rake angle. You set it up to part 1" dia stock with edge on center. Then you need to part 1.5"dia stock so you simply extend the blade. But now the edge is above the center line. therefore you also have to re-establish edge center by dropping the toolholder or however you make your adjustment.

- How are you establishing that the blade is set exactly perpendicular to the stock axis?

- Do you have the edge ground at 90-deg (ie no angle to the edge looking down at the Tee). Some folks grind an angle one way or another so that it will part with no bib on one side or another. I haven't found it makes much difference one way or another if its working right. But I do know that this profile can draw the blade in at an angle during the cut. It then binds up & bad things happen.

- How thick is your T blade & what kind of holder? A lot of problems have been traced to POS import blade holders that do not clamp the blade securely. Tightening actually cants the blade over which is A) now at an angle = bad B) not supported by the tool holder = bad

Feeding by hand should be no different than power feeding, at least to give you a feel for whats going on. You can slow down feed or back off to clear chips... all important things to get established before you let it go autopilot.
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Grinding to end of a parting tool at an angle to reduce the pip at the end of the cut will make the chip wider than the slot that it is trying to escape from, inviting the chips to bind up in the slot and subsequent disaster; this is avoided by insert geometry that tends to narrow the chip with a radius formed in the insert's top edge. I have seen tools in HSS that have been modified in that manner, how well they work is not known to me, but what is plain to see is that such grinding creates a delicate point on each side of the point of the tool, subject to wear and possible chipping.
 
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SLK001 said:
It just takes way too damn long. Plus, your arm will ache for hours once you're done.
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huh?
my bandsaw would cut 1 1/4 in less than a minute with me doing something else

op trying to part that off appears to take hours without success
 
He said hack saw not band saw. I remember using a hack saw to cut stuff down. I bought a used porta band. Best $50 I have spent for the shop.

Joe
 
Liljoebrshooter said:
He said hack saw not band saw. I remember using a hack saw to cut stuff down. I bought a used porta band. Best $50 I have spent for the shop.

Joe
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aaah were was hack saw mentioned? :)
 
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