About to give up on this follow rest - am I not understanding it, or is it not too useful?

WobblyHand

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Although I understand the concept of a follow rest, the one that I have is defying use. Perhaps, I don't have the right tooling, or whatever, but I can tell you, I'm getting frustrated with it. I could rant about what I don't like about it, but at this point, I'm just seeing if I could use it.

Ok, what am I trying to do? Single point thread a long rod. Specifically 1.5" of 1/4" rod. Since it's long and skinny compared to its diameter it would seem using a follow rest would make sense. That's the only thing making sense. Ok, had to cut down the number of threads sticking out from the left side. Easy. (Why did they design it with the nuts on that side? It restricts how close you can get to the chuck.) Now I can get 6mm closer to the chuck. Since the workpiece is long, maybe I should support it with a live center. Ok, done. Let's now check both ends to see the tool can cut where it needs to. Chuck side seems to be ok. Live center side, nope, the follow rest jaws hit the live center. To make it clear I'd have to cut 1/2 the jaw width. Seems like a lot.

What is the solution space here? Cut the jaws? Use a different live center with a tiny nose? Cheapest one I can find whose dimensions are close is $96. Use a dead center that is half cut way so I can thread to the end (~ $10). Anything else? Cheapest after filing the jaws is probably the cut dead center.

It's funny, as I single point threaded a 1/4 rod before and used nothing. Threads didn't come out the greatest, but they were functional. Thought I'd use the follow rest, umm, because I have one, but the one I have has serious deficiencies, in installation, in visibility, and in use. Not sure I will be able to easily tell when to stop, since the visibility is poor. To safeguard against hitting the chuck I have put in a carriage stop.
IMG_20200507_144616.jpgIMG_20200507_144632.jpg
Kind of stuck for the moment. Any helpful ideas?
 
I would use a die and die holder backed up by the tail stock quill . Put lathe in neutral and thread by pulling the chuck through by hand .
 
It seems you are using it correctly. Never used one myself.
I can see how they could be handy when knurling a part where extra support is required.
 
I would use a die and die holder backed up by the tail stock quill . Put lathe in neutral and thread by pulling the chuck through by hand .
I bought a die holder for my lathe and it didn't seem to hold the die flat enough for my liking. With the admittedly cheap die, it rocked. It gave me no confidence that the die would start correctly. Perhaps I don't understand how it should work, but I'd think one would want to have the die supported uniformly on the back face. I am definitely considering making my own. It seems like it would make a nice lathe project
 
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Think I'll get one of these. Carbide tip. Might make things a little easier. Should be able to thread from the end.
Carbide tip half dead center The drawing in the listing is dimensioned, unlike some of the other tooling I've seen.
Machining is what you eventually do, after waiting for tooling... Guess I get to move on the the next project, err, tool gathering.
 
If you slid the rod out further, and rode the follow rest on the rod and cut to the right of the jaws it would work better; a follow rest is not really appropriate for threading vee threads and when they get sharp they will cut the jaws, it was not a good application for the follow rest, a center would be all that is necessary, and a dead half center would work just fine. For acme threads they work just fine due to the straight flat at the top of the threads.
 
Yes tool gathering but tool making is more fun.
The half center pictured above can be very useful.
Your live center is very bulky so you have to make your own from an MT2 center turning in an MT3/MT2 adapter.
For starting a die straight with whatever system it is good practice to chamfer the end of the rod to fit the taper on the die.
Re the follow rest what benmychree said.
 
@benmychree Thanks for the tip. Not sure how much adjustability I have on this follow rest. The rest has been quite limiting. By that I mean it's not designed to be easily used. It was hard to install without removing everything on the compound slide. Hard to change or move tooling, hard to see the tool tip, it's proven to be a pain in the posterior in many ways. Was worried about the threads cutting the jaws and you have confirmed it. Well, guess I'm getting a dead half center out of this exercise, so it's not all bad. Once I get brave enough to cut my own acme threads, guess I'll take it out of the box again.
 
Usually you set the tool to cut to the right of the jaws, if only just barely, one thing I note is that they commonly do not work well with QCTPs because of the large offset of the post, sometimes for threading long acme screws I remove the QCTP and use the rocker tool post with old fashioned tool holders. For my cute little 9" Monarch I made a follow rest that locates the jaws over the center of the cross slide.
 
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