Cutting metals w/ Tap & Die

[spindlecraft]

Just a quick question about taps & dies.

As I dive deeper and deeper into the kitless world, I find myself wanting to make my own mandrels and such to hold various pieces on the lathe.

I've purchased some brass & aluminum rod stock. My bigger question though is – is cutting threads in this material going to damage or dull my taps/dies?

At over $200 for a single tap & die set... I am wary to risk it, if it's going to damage the die, or cause it to become dull or cut less effective threads in my pens.

 

[Paul in OKC]

For brass and aluminum you should be fine. Use something to lubricate the cut.

 

[Drewby108]

Definitely use some cutting fluid.

If you are hand tapping, make sure you break the chip (reverse a quarter turn or so) every so often to relieve pressure on the cutting edges of the tap/die.

If you are power tapping on the mill/lathe, make sure your blind hole is a bit deeper than you need to keep from bottoming out and breaking stuff.

Admittedly, I have only ever done single thread taps, but multistart should be the same process.

 

[egnald]

I used to go through about 3 taps for every hole in steel. Then I discovered Tap Magic. Amazing stuff. Far better than any kind of oil I used before. - Dave

 

[Valleyboy]

You'll be fine using triple lead dies on brass and aluminium (I'm guessing they are triple lead based on the price you mention). They are both much softer metals than the hardened steel dies.

Be sure to clean the die thoroughly afterwards especially with brass. Small chips can remain in the die and you don't want that messing up your threads when cutting your pens.

 

[rherrell]

I use 12L14 steel for all my mandrels, the L stands for "lead" and it makes it softer than other steels. I have no problem using triple lead taps and dies. Use a 50% thread engagement when choosing your tapping drill and reduce the size of your tenons by at least 10% of the pitch.

 

[wimkluck]

I use 12L14 steel for all my mandrels, the L stands for "lead" and it makes it softer than other steels. I have no problem using triple lead taps and dies. Use a 50% thread engagement when choosing your tapping drill and reduce the size of your tenons by at least 10% of the pitch.

Soon I want to start making costum fountain pens. As a Dutch person, I don't exactly understand what you mean.
I do have a tripple tap and die set M13 x 0.8 The tennon will be 13mm - (10% 0.8) so a will need a tenon 12.9 mm
I put thread engagement in Google translate. But that did not make it clear. The wire I cut inside the cap must be 50% longer than the tenon?