A few months ago I decided I had enough with using my traditional die holder in the lathe and set out to make a proper sliding die holder. It is a very good beginner project that is straightforward to make and also is one that is exceptionally useful.
I started out with a design in Fusion. The design consists of 3 manufactured parts, a body, an arbor, and a handle for extra leverage. The body is designed to hold 1″ dies – a size that I have standardized on in my shop due to primarily expensive. As die sizes climb the prices move up exponentially and due to that I generally single point large threads. If you have larger dies the design is very easy to modify to accommodate larger dies.
Traditionally most people don’t use a sliding die holder to hold taps. I’ve always started taps in the lathe using the tailstock. If the tap is small enough I am brave enough to power tap – being sure to leave the tap a little loose to make sure when it bottoms out it slips to avoid broken taps. I had the thought to incorporate an inexpensive ER collet chuck into the design to facilitate holding taps. In this design the ER16 collect chuck stub is held in the end opposite to the die holder with a couple of set screws.
Besides being a pleasure to use with dies, it also works exceptionally well for small taps. I don’t use the handle when I power tap with it – the handle is really only used for dies. Now when you are tapping blind holes you can simply let go of the body and the entire body spins. You can also feel when the tap reaches the bottom of the hole as the amount of force required to hold the body quickly climbs – at this point you simply let go, allow the body to spin and shut the lathe off.
Standard ER collets do a very good job of holding taps in the home shop. You can get ER collets with an internal square that engages the tap drive but I’ve found it unnecessary for home shop work. They are also more expensive and harder to find online – most industrial tool supply places can get them.
If you would like to build one yourself I made up a full set of drawings for the shop, and I’ll also provide 3D CAD in the zip file (iges and step):
I also made a video the project: