Tapping (die-ing) helper

[GrahamRounce]

This useful 3D-printed thing keeps the die-holder level.
The rod you're threading goes through the central hole, and the die is held at 90° to it.
It could probably be fancied-up to accept a range of rod sizes, but I've just printed what I needed - a 4mm one and a 5mm one.

 

[ChaiLatte]

A couple of observations:

1. It relies for its accuracy on the outside of the die holder being concentric with the inside of the die holder. On a cheap die-cast item, that might not be true.

2. It relies on the die being held concentric to the inside of the holder. That is somewhat more difficult to achieve than the point above unless you use an unsplit die whose OD exactly matches the ID of the holder. The single clamping screw provided on the holder would push downwards any die that does not match the holder and hence off centre.

Providing (1) is true, you could centralise the die in the holder by threading it onto something that already has threads cut onto it and then tune the adjustment screws so the die remains central in the holder when the threaded item is removed.

 

[Amplidyne]

If it works, then it works, but I reckon it'd be better with the die holder clamping into the guide, otherwise it might twist.

 

[GrahamRounce]

Ok, I didn't think of all that. But it works brilliantly with my Powerfix (Lidl's) die holder (otherwise I wouldn't have posted it)! A good, professional-looking thread, far better than I've previously done by hand. And getting it started is a dream in comparison!

 

[Phill05]

A good, professional-looking thread, far better than I've previously done by hand. And getting it started is a dream in comparison!

Good for you it's not all about what the book say's they look very good.

 

[Amplidyne]

Ok, I didn't think of all that. But it works brilliantly with my Powerfix (Lidl's) die holder (otherwise I wouldn't have posted it)! A good, professional-looking thread, far better than I've previously done by hand. And getting it started is a dream in comparison!

Me thinking aloud more than a criticism. I'm a big fan of 3D printing tools like this. As long as they work it's a win.

 

[Fergie 307]

To be fair the main issue with cutting threads is where either the die or the tap is not perpendicular to the material being threaded. These address that problem very well.
You will get even better results if you invest in some high quality dies and taps in the sizes you most commonly use. The sets from Lidl/Aldi are ok up to a point, but not the greatest quality and will soon wear out of used regularly.
They are good value for occasional jobs on relatively soft stuff.

 

[Vulcan]

Being plastic I can’t see it lasting very long? You used to be able to buy die stocks with an adjustable guide but I found they didn’t work very well. These though are brilliant, I have three different sizes. The HSS die is molded into a plastic stock with a metal guide bush. They work very well.

 

[Amplidyne]

Printed plastic is surprisingly tough, especially if you use one of the tougher plastics. Even PLA isn't bad, and PETG is even better.
Useful link that thanks. I've not long bought some Presto dies though. The cheap set I've had for ages were difficult to start, and not adjustable. Relegated to cleaning up existing threads.

 

[MorrisWoodman12]

Slightly off thread but I've used old dies to a) hold a screw when I'm cutting it to length and b) to clean up the thread as I'm removing the screw from the die. I find this works better than using the traditional nut to clean the thread.

 

[Fergie 307]

Printed plastic is surprisingly tough, especially if you use one of the tougher plastics. Even PLA isn't bad, and PETG is even better.
Useful link that thanks. I've not long bought some Presto dies though. The cheap set I've had for ages were difficult to start, and not adjustable. Relegated to cleaning up existing threads.

The difference using a really good tap or die, like your Presto ones, is like chalk and cheese. Split ones are good as you can alter the size to get a really good fit.
You can buy thread chasers, or make your own.
If you have a high tensile bolt or nut just cut grooves down the thread with a disc cutter or Dremel. Run a bolt or nut over them to make sure the thread is good, then harden them by heating till red hot and quenching in oil or water, then heat up to a straw colour and let them cool naturally to temper.
Handy for some obscure thread where buying a tap or die is too expensive for a one off job and you just need to clean them up.

 

[Amplidyne]

Oh yes, I was having trouble getting some new split dies started. They were a cheap set. The Presto ones start easily. I remember thinking with the old (old!) set I've got that being solid dies, they're more like die nuts than thread cutting dies. Still as I say they're handy for cleaning up old threads.
Good tip for making a tap for cleaning up.

 

[GrahamRounce]

Slightly off thread

Hoho

 

[stuart little]

To be fair the main issue with cutting threads is where either the die or the tap is not perpendicular to the material being threaded. These address that problem very well.
You will get even better results if you invest in some high quality dies and taps in the sizes you most commonly use. The sets from Lidl/Aldi are ok up to a point, but not the greatest quality and will soon wear out of used regularly.
They are good value for occasional jobs on relatively soft stuff.

Or just for cleaning up damaged threads.