Methods for parting off larger diameters

This may be obvious to all you pros, but I thought I would mention it. I have always cut off large diameters with my hacksaw. The cut was less than pretty. It was just the ordinary simple hacksaw with the wing nut to secure the blade. Then I discovered high tension hacksaws, perhaps from someone on this forum. What an amazing difference! I recently cut a end off a 2" diameter aluminum rod. I hardly had to face much off to get it trued up in the lathe.

David
 
So as mentioned above, I threaded the body at 24tpi to thread a new pulley on.

So, I actually did the math on this one. Threaded the body, pretty much without looking at a caliper or dro, cause frankly, it didn't matter. But from that male thread, I mathed the female side...... it's f****ing perfect! First try! No test fit, only boring to diameter with an boring gauge and the calipers, then sorting out the major/minor thread diameters from the chart I have. BAM, perfect first try. No slop, it's not tight. I can't believe it! Hahaha.

So, I screwed up by cutting it short, then knocked it out of the park with an awesome fix. Now I'll chuck up the body with the big chunk threaded on and cut the pulleys.

IMAG0903.jpg
IMAG0902.jpg


The neighbours must think I'm crazy. When I threaded the pulley on I started laughing hysterically. Lol. Things don't ever work out perfect on the first try........
 
So as mentioned above, I threaded the body at 24tpi to thread a new pulley on.

So, I actually did the math on this one. Threaded the body, pretty much without looking at a caliper or dro, cause frankly, it didn't matter. But from that male thread, I mathed the female side...... it's f****ing perfect! First try! No test fit, only boring to diameter with an boring gauge and the calipers, then sorting out the major/minor thread diameters from the chart I have. BAM, perfect first try. No slop, it's not tight. I can't believe it! Hahaha.

So, I screwed up by cutting it short, then knocked it out of the park with an awesome fix. Now I'll chuck up the body with the big chunk threaded on and cut the pulleys.

View attachment 226224
View attachment 226225


The neighbours must think I'm crazy. When I threaded the pulley on I started laughing hysterically. Lol. Things don't ever work out perfect on the first try........

Way to go!! Looks like someone was watching over you, feeling sorry for your mistake, and helped you make up for it in a superb way!

I've had my share of parting woes on my 7x10 as well. I finally read enough advice about it to ignore the convention of "how to grind a parting tool" and redesigned mine so it cuts much better. The top edge, viewed from the side, would look like the cross section of a teaspoon if you sawed it down lengthwise through the middle of the handle and on through the spoon part. A nice "C" shaped upward sweeping cutting edge. It works very well shaped like that.

BTW, I got the idea for that shape from how I grind fly cutter tools to do aluminum. Visualize the "paddle" style ice cream scoop scraping across the top surface of a bucket of ice cream and rolling up a scoop of ice cream, and you get the idea.

Glad you were able to find a solution! :)
 
Use your lathe to face and cut to length the riser blocks and I would add a set screw to your threaded fix. Machine will be run in reverse at times. Have the set screw thread into your male portion but don t penetrate.
 
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I come to this thread late. When parting diameters that are larger than your comfort zone, sometimes a machinist jack supporting the underside of parting tool can take a lot of chatter out and allow you to keep the pressure on the feed and go to town. A machinist jack could be as simple as a hardware store coupler nut and a bolt with lock nut.
 
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