Thread Bar Project, nothing is going right and I need help

I hate to bring this up but using the compound is not required when threading, one may go straight in with the cross slide to great effect, this is not to say that it does not work but it takes longer to do, time is important.

I suspect that you are using a spindle speed that is entirely to slow even for HSS tools, wick it up a bit.

I also realize that the first time one threads to a shoulder it is a butt puckering experience at best, experience and practice will make it easy at some point, a few crashes along they way are inevitable.

Good Luck

As a side note, if you are younger then 30 and are thinking about this as a career choice then Bravo to you, I have worked in machine shops for 30 years and there are very few young people entering that workforce, it is excellent for us old guys however, they have to keep paying us a nice wage until we die or retire. Where I currently work we do a good deal of work for the manufacturing automation industry making equipment that replaces people, someone has to make the robots.
 
You can always drill the center hole a bit deeper, it does not have to be much, just a touch. Make sure the tail stock is locked in place before you drill


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I already drilled it about 4/5 the way up the taper, I think it will be fine. Anyways here's the HSS tool bit I grinded that I have to use for threading this bar. The center point is a bit off to the left so I think I'm going to re grind it so I make the point in the middle more. It's a perfect 60 degrees though so I'm not sure if I wanna mess it up. How big of a deal would it be if it's a little to the left?

Also, would taking a TON of .003-.004 passes dull this tool quicker than taking like .010 passes with the compound at a time? Just trying to find the best way to complete an entire thread without sharpening the tool while in the middle of a thread...thanks guys

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You are better off if you offset the point to the left so that you can cut into the thread relief without the side of the tool making contact. I don't have a pic of my tool but it looks exactly like this (stolen from Conrad Hoffman without his consent - it was on the net so I'm posting a link): http://conradhoffman.com/shop_images/thread_tool.jpg

Also, at the very tip, just put a very tiny flat. If the radius is too large you will have that profile at the root of the thread. There are specs for this but for your project, a flat about 1/64" across is enough to keep the tip from cracking off.
 
thank you, my tip actually does offset to the left i think. i will regrind it and put less of a nose radius on it.
 
Try offsetting the tip way to the left like the pic. You'll be happy you did. Also, try for about 10-12 degrees of side relief - the tool will cut better for you.
 
Thanks Mikey. When you say offsetting to the left, you mean make the left side top side shorter and the right side way long like that? That would mean when I go to fish tail center gauge it on my compound, I would be turning the tool holder to the right to compensate and have the 60 degree angle in the middle right? The way I have mine now, I have to turn the tool post to the left and it runs into clearance issues with my lathe dog spinning. Hope you understood all that. I drew a picture to show you what I mean. also do you have a better pic that i can see without turning my head upside down lol and clearer one. Here....

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No, I'm referring to the shape of the tool itself. If you look at the pic I linked to, you will see the 60 degree point is not in the center of the tool. Its off to the left side. This allows you to get closer to the thread relief before the body of the tool gets in the way. I also suggest you use a larger relief angle when you regrind as I said and incorporate a smaller flat at the tip. The flat does not need to be round; it is there to prevent the tip from cracking off in use. There is actually a spec for the width and shape of the tip but few use it unless your thread form must pass inspection.
 
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