die holder with MT4

[taydin]

Hi,

I want to cut a 1.5mm pitch thread to a 17mm silver steel rod. Given my current not so advanced thread cutting skills on the lathe, I want to use a die to cut the thread. I was wondering if there is a tool like this:

Something like a collet holder with an MT4 taper, which will fit my lathe's tailstock. But instead of holding a collet, it holds a die in it. It also allows the rod to be threaded to go in maybe 50mm or so... Is there such a thing, or should I continue working on my thread cutting skills?

[Ian B]

The quickest way would probably be to buy one of these:

http://cgi.ebay.co.uk/RDG-3-MT-TAILS...item56351f931d

(they ship worldwide), and then stick it in a 3 to 4MT sleeve. Alternately, as you have a lathe, it'd make a nice little turning project, and you can size it to your taper / die size / length of rod requirements as you wish.

Some work by reacting the die's torque on a keyway on the shaft sticking out of the tailstock, others use a torque arm that rides along the top of the topslide, or a steel bar sticking out of the toolpost.

The next step up would be to buy a Coventry die head or similar, which are usually used on capstan / turret lathes, but can be adapted to tailstock taper mounts.

Ian

[fraker]

Hi.

First of all, do keep working on your threading skills. It can be / is fairly difficult to master the first time out. but, trust me, it DOES get easier. After a while you'll be wondering what all the fuss was about and churning out threads without thinking about it too hard.

In the meantime, i think what you are looking for is...

http://www.arceurotrade.co.uk/Catalo...ck-Accessories

Item No: 090-070-00602

These are in the UK but something similar should be available wherever you are.

As usual, no affiliation with above. just a happy customer.

Hope this helps and good luck with your threading endeavours.

Bill

Sorry about that erronious link, that's NOT what your looking for at all. Apologies.
What your looking for is in the reply above this one.

[Boucher]

An old scrap drill is a good source of the M4 tang. A socket can be cut into it if it is large enough or an intermediate bushing can be constructed. If you have a drill chuck for the tailstock it can be used to hold a die socket with a straight tang. Just a couple of thoughts.

[JCHannum]

A tailstock die holder is a simple project. If you have a tailstock drill chuck, you can make one with a straight shank to hold with the chuck. These are also available from tool suppliers and are more economical that those with MT tangs.

Even when threading with one of these, the thread can have a tendency to wander. If a concentric thread is the desired outcome, the best practice is to initially singlepoint the thread and only use the die to clean up the thread. This will give you a chance to practice your threadcutting and still produce an acceptacle finished thread.

Looking again at your original post, that is a large thread you are cutting and singlepointing the thread first will also reduce the cutting forces the die would encounter substantially.

[taydin]

Thanks for the responses guys. Very much appreciated.

Now that I know this type of tool exists, I have asked a number of places here about the availability. Nobody has it. My father gave me lots of drills with MT3 shank. I can definitely sacrifice one of them for this purpose. Just need to figure out how to do the following:

- attaching the MT3 shank to a piece of round stock. Do you think I should weld the MT3 to the round stock or is it better to drill the round stock 20mm, machine the tip of the MT3 20mm and then mate them?

- Making replaceable rings to hold various size dies.

[taydin]

Even when threading with one of these, the thread can have a tendency to wander. If a concentric thread is the desired outcome, the best practice is to initially singlepoint the thread and only use the die to clean up the thread. This will give you a chance to practice your threadcutting and still produce an acceptacle finished thread.

Concentricity isn't really necessary. This rod will be used for my milling machine's levelling pads. The rod that came with the pads is too short, so I am making longer ones. Standard off the shelf threaded rod has a different thread pitch, so doesn't work for me.

But first creating the grooves on the lathe and then going in with a die is an excellent idea. When I cut a thread, the first few passes are usually good ...

[dockrat]

make one with a straight shaft that you can put in a tailstock drill chuck. Here is one I made:

[JCHannum]

This rod will be used for my milling machine's levelling pads....

If that is the case, you can save yourself some grief and expense by using mild steel instead of silver steel. You will have no advantage with silver steel, and it is much more difficult to thread.

[taydin]

You will have no advantage with silver steel, and it is much more difficult to thread.

Hmm, I didn't know that. All threading attempts I had made on the lathe were with silver steel so far. The compound was set at 30 degrees, the insert type thread cutter was centered correctly, used oil and advanced the compound by 0.05mm for each pass. After a few nice passes, the threads started to disintegrate with further passes.

Could you please elaborate why silver steel is difficult to thread and what the correct procedure is to do it correctly?