When should I thread, when should I use a die?

[wawoodman]

So I want to make little knurled head screws, say 8-32 x 3/4 inch. Would you do the threading with the lathe, or use a die? How do you thread all the way up to the head (or did I just answer my own question?)

When would you use one or the other? Big stuff? Little stuff?

 

[pdentrem]

In this case I would use a die. I would thread on the lathe when I have to due to a special thread or no die available in the time remaining.
As for threading up to the head in your case is it really required? Usually there is no thread up to the head of a bolt as the assumption that a washer or the bolt is passing through a unthreaded hole to reach the nut or another threaded part.
Pierre

 

[DMS]

What I have done to thread up to a corner with a die is to tap the normal way as far as you can go, then flip the die around and go backwards. You can usually get another half turn or so. You still won't get right to the corner. Maybe you can reduce that area so that it doesn't collide with the mating thread?

If you are making a bunch of these, single point threading is going to take _forever_. I would recommend the die. Another option is to drill a hole and tap (making a knurled nut). Then locktite in a piece of all thread.

As to when to use what, dies are usually much faster, but if you really need your threads to be concentric with the shaft, you can't beat single point threading. I usually use a die if I can get a way with it.

 

[Tom Griffin]

Mike,

You can do it however you like, but a lathe cut thread will be more accurate in both pitch and fit and a die cut thread is quicker. It sort of depends on the application as to which one is better.

You can cut a thread all the way to a shoulder by stopping the spindle of the lathe (leave the half nut engaged) and turning the chuck by hand, withdrawing the tool at the end of the thread.

Tom

 

[8ntsane]

If your only doing one or two, using a die would be probably easyer for you. The small threads like that can be trouble some for a novice. You should be able to get up close to the end, but will need to leave a little room. You can cut the thread as Tom suggested. Its all a matter if your just learning, or have some experiance allready. If your just learning the threading game, then use a die for now, and learn on some larger threads for single pointing.

 

[Bill Gruby]

If I were doing this and only one or two were needed the Die is the way I would go. The flipping of the Die will get you as close as you need to get. If I were doing many of these then single point lathe cut is what I would do. Fine threads can get tricky, they don't go very deep.

"Billy G" )

 

[swatson144]

To have a thread to a shoulder you can cut a groove 3-4 threads width, the full thread depth near the head when you turn the blanks. That will ensure there are no partial threads to stud bind.

Steve

 

[george wilson]

Yes,flip the die to get to the shoulder. I am making some 3/8-16 the. brass parts,and flip the die to thread the last 1/2"of length due to the die holder getting in there way. This length of backwards flipping works fine with brass. Less for steel.

The trouble is,threading with the lathe is the only way to get threads true to the axis of the part. Die cut threads may wobble when screwed in. Depends how critical your application is.

 

[wawoodman]

Thanks for the guidelines. That tells me just what I wanted to know. For some reason, I was thinking that the die was a "sissy" way to go, and real men used the lathe.

I'll go ahead with the floating die holder project!

 

[xalky]

Thanks for the guidelines. That tells me just what I wanted to know. For some reason, I was thinking that the die was a "sissy" way to go, and real men used the lathe.

I'll go ahead with the floating die holder project!

The sissy way is to go to the hardware store and buy some.:rofl: Which is probably what i would do. I have dies and a lathe, but some things are just more efficient to buy. :whiteflag: