Am I the only one who can't part off on the lathe to save his life?

There's a YouTube video with a guy who uses a steel plate across the ways and the cut off tool has a shaft that rides on it to stop the cutter from flexing . Small LATHES don't have the heft to not move when parting . You can alter the cutter geometry to help too. Parting blades with a tiny notch in the center seem to cut easier thus less pressure when feeding . I'd suggest cking some of those also
 
Glenn Brooks said:
I have constant trouble parting with cheap, hobby quality, parting blades, and no problem whatsoever with high quality blades. I’ve come to the conclusion that our hobby suppliers love to sell pretty looking junk steel parting blades. They look great but break constantly, causing an endless consumer demand for inferior, unsuitable parting tools.

Try buying one top of the line parting blade and see if it makes a difference. My guess is, your parting problems will go way down.

Glenn
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A lot of good suggestions but what Glenn mentioned above helped me a ton. I used to part using this and 50% of the time much excitement ensued!
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Finally sprung for this and wow- night and day difference. (Don't mind the excessive stickout on mine. I frequently part off 3"+ diameter nylon so that why I have them set so far out.) Set the blade for the minimum stick out possible.
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Well i got it parted off. I think my main problem was the tool. I reground it and spent more time honing it until it was really sharp. made a huge difference. I also slowed the speed as slow as my lathe would go. There is definitely some art to it though. Even with this if I fed too slow it would start to chatter, so against my will I fed in faster and it would cut awesome curly chips! But…..too fast and chatter again. Have to learn the feel i guess. Thanks for all the help. I will also buy one of the above tools.
 
Joe Pie has a decent video up, and he mentions the same thing that UlmaDoc mentions above about the percentage of cobalt.
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I use surplus from the auctions. Have a few HSS 1/2 Armstrong #86-257's and their geometry is 'Right or Straight' They are square/perpendicular on one side.
Then I have some other wider ones that I need to get some holders for, and then a couple of carbide insert styles that I hold in reserve because of the cost of the inserts.
 
I,to, had troubles parting off. Started with a tiny thin blade with uncoated inserts. Not much joy. Was forced to try coated inserts and WOW, what a difference. I then went to a thicker blade in a custom made holder <designed to get the blade closer to the center of the QC tool block. Again, a great increase in my abilities to preform the work. I now have a CXA block with much more robust tools and holders. Mass is good!!! Tight is just as important! I seldom break an insert and usually replace them when they are acting up before failures occur. Lastly I had to learn you can't sneak up on a cutoff operation. Feed it more that you would ever think it would take! And make sure it's square to the work! Good luck, and keep us informed of your progress!
 
I found those "T" cross section parting blades work exceedingly well on my floppy 9x20.
My solid plinth instead of a top slide/compound also made a gigantic difference.
 
Lots of good info here in thread. I will add make sure, absolutely sure you are on center, and that blade is square to chuck, to be sure, dial it in with test indicator, even being off a thou or two can make parting a nightmare. I like sulfur cutting oil for steel, kerosene for aluminum, dry for cast iron and plastics. Lots of cutting oil on steel and keep the feed up, if you baby it, you can get work hardening and then when you add more pressure and start cutting again you get a big dig in and snap, the sound of more money down the tubes.
 
Cheeseking said:
Finally sprung for this and wow- night and day difference. (Don't mind the excessive stickout on mine. I frequently part off 3"+ diameter nylon so that why I have them set so far out.) Set the blade for the minimum stick out possible.
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Cheeseking,

What machine are you using that it makes such a difference? Something rigid, like a Bridgeport, or something not so rigid, like a mini mill, or something in between? Thanks.

Tom
 
You're in the same boat as everyone, parting off is a pain...but you learn what works and what doesn't. Keep at it!!
 
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