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Parting blade thickness for threaded rod

Bill D

Apr 1, 2004
Modesto, CA USA
I need to cut some 3/8" all thread to various lengths to make studs. I could hacksaw it and true the ends on the lathe. I have tried to part it off and my parting blade tends to follow the threads and jam, snap and other bad things. Lathe is a 13x40 with an Aloris bxa7 tool holder. Should I go thicker or thinner blade? Thicker seems less likely to deflect but needs more cutting force. Thinner less force but more likely to bend and snap. I am using hhs blades not carbide insert.
Can you lock the carriage from moving? You might try feeding to the thread root using the compound set at an angle, then finish the cut with the cross feed. Confirm your parting tool is on center, very critical with a small OD.
I like the ideas of one cutter to make a nice flat or vee groove then switch to the cutoff blade.
In the past I have tried using a round insert and find the sides chip. I think they are really only supported at the front.
If they are relatively short set screws are pretty handy.

Other than that using a grooving tool works well if you don't have luck shortening your parting tool hang out.
Regular all thread
Move the blade into the holder so that you only have minimal overhang.
Regular all thread I have ZERO issues, on the most worn machine in the entire universe.
Perhaps it's extremely hardened

If it's too deep/hard:1707415923175.png
I have a lathe. Thats not what I would use. I have cut a LOT of all thread, from 1/8" to 1", hundreds and hundreds of parts for some projects.
I cut to length with the cold saw, touch up the ends on the disc sander, and I can do ten of em in the time it takes to chuck up one in the lathe. I have had a cold saw since 92, but before that, I cut em with a horizontal band saw, still way faster than a lathe. I suppose if you had a cnc lathe with a bar feeder, you could make a case for it, but even then, some jobs are still fast with the old armstrong methods.
I ended up doing it on my power hacksaw, patented in 1912. I just used some wood blocks so the threads did not get mangled in the vise. Then a quick round over on the grinder.
Bill D