DEALING WITH 4-40

Maybe not the best way to do this, but it works. You push the face of the drill chuck (with the jaws retracted) against the die holder. This keeps the die perpendicular to the rod. If you chamfer the rod, and the rod is the correct diameter (not too big, or too small) the die will start. As you turn the die, make sure you feed in the tailstock. That way the die continues to be straight.
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Hope this helps.
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WobblyHand said:
Maybe not the best way to do this, but it works. You push the face of the drill chuck (with the jaws retracted) against the die holder. This keeps the die perpendicular to the rod. If you chamfer the rod, and the rod is the correct diameter (not too big, or too small) the die will start. As you turn the die, make sure you feed in the tailstock. That way the die continues to be straight.
View attachment 392125
Hope this helps.
View attachment 392128
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wish I had some nice collets......... so your saying the die/holder has to be flat against the TS chuck?? just had a thought, what if the round work piece went in the TS chuck thru the die but wasnt tighted down yet spun around in the TS chuck to really hold things straight ....... whatdo ya think
 
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Yes, it will work with a regular chuck. (3J, 4J, 6J, ER, 5C or whatever) It's really no different. Rod to be threaded held by the lathe chuck and the die holder backed by the drill chuck.
 
riversidedan said:
wish I had some nice collets......... so your saying the die/holder has to be flat against the TS chuck?? just had a thought, what if the round work piece went in the TS chuck thru the die but wasnt tighted down yet spun around in the TS chuck to really hold things straight ....... whatdo ya think
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The lathe chuck is really capable of clamping the rod, so why not use it? It has the advantage of allowing a long rod to continue through the spindle, unlike with the tailstock. Personally, I would not do what you suggest. The lathe chuck is designed to hold the rod absolutely straight. In fact, it is probably better aligned to your ways than the tailstock is. It's better to allow the diestock to float on the face of the drill chuck and have the rod center the die. Try it and see how it works. If you don't like it, try something else. The method I explained works for me, likely it will work for you!
 
Starting a die true to the work is a problem in even the larger sizes, 1" and above. The method I use for smaller screws, Nr 2 and Nr 00 should work for a middlin' size like Nr 4. Start with the proper size, .060 +(4x.013). That yields 0.112". Then extract the few thou for top clearance. A very few thou for Nr 4. Then for the first 1/4 inch, remove down to .113 less .025 (.088") for a slim fit internally. Once the die is slid onto the undersized section, start cutting. For something as large as Nr 4, I would put the stock in a lathe and hold the die by hand or maybe a pair of "Channel-Locks" so it can be released quickly.

The above is for making long threads, like all-thread. For machine screws with 4 or 5 pitches, I just chuck the part and use the face of the tailstock chuck to square the die. There are occasional times when the screw end is exposed. There I trim the end as described above, run the die, and before removing the die clip off the undersized portion and excess length and trim up with a file. It works well enough for the small sizes I deal with. Nr 4 should do well enough.

For long threads I often use oversized stock. Just trueing up a half inch or so for the die to bite. The most common thread I cut is 2-56. The rod is 3/32 brass. At ~.093, a fuzz over size for Nr 2 at .086. Once the die is started, it will shave off that little bit of extra. Be advised, brass is soft enough for that "shenanigan". As is raw aluminium. On the other hand, steel is tougher and may not shave so easily.

EDIT: adjusted Screw sizes
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am thinking I got the wrong die...........as in thiers teeth in one side of the die and the other 1/2 is no teeth
 
riversidedan said:
am thinking I got the wrong die...........as in thiers teeth in one side of the die and the other 1/2 is no teeth
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Not sure what you mean by that. A die should look something like this:
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The die is usually round, but doesn't have to be, and it has gaps between the threads, for the swarf to be ejected. Does your die look similar to this? Some dies have a split, but they don't have to have one.
 
Why don't you take a picture of your die and post it here. A picture is worth a thousand words!
 
@riversidedan we are trying to help. If there's something confusing, please ask. Since we're remote from you, we can't see what you see, or even know what your setup is. Pictures help us a lot. Or, if it is hard for you to post pictures, pretend you're on the telephone and you're talking to a friend about it. On the phone, you would describe the situation, ask a question or two, listen and talk again. It's the same here, although it's probably slower.

Don't get too frustrated, we've all been there. It's hard getting started. My first lathe came home 2 years ago. I started from zero. I fumbled a bit, but improved. Asked many questions on Hobby Machinist. From some of your pictures, it appears that you are making some good things. Your skills will continue to improve.

So keep communicating and posting. We will be able to work through most of the machining questions. Lots of good people here that want to help. Keep plugging away, and it will get done.

There are no stupid questions. Just ask. That's how we all learn.
 
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