Hss Die On Stainless?

[darita]

Is it harmful to a HSS die to use it on a stainless steel blank? It's a very small die, 1-56, so I don't want to damage it. Thanks.

 

[4GSR]

Should work fine as long as you flood it with a good cutting oil.

That's going to be a tough one to thread from scratch! Going to single point the thread first, then finish with a die?

 

[darita]

Ok...here's the deal...I'm starting with a 1-72 screw and using the 1-56 die to try to create a 1-56 screw. Not perfect, but that's what I have.

 

[RJSakowski]

Ok...here's the deal...I'm starting with a 1-72 screw and using the 1-56 die to try to create a 1-56 screw. Not perfect, but that's what I have.

From your previous post, I would guess you are still looking for a solution for the clock screws. I also assume theat you are concerned about the cosmetic appearance of the screw head more than the holding power.

Be aware that a die will not thread to the shoulder. You can reverse the die and get a little closer but you will still be about 1-1/2 threads away.

Additionally, at some point, you will be cutting away the peaks of the original thread. Recutting a 72 tpi thread to 56 tpi, this will occur on the the second full thread. Picking a thread pitch closer to your desired 56 tpi would move that point further. Instead of a 1-72, you might consider a 1-64 or a metric M2-.4mm. The drawing below shows that the difference between the 72 tpi and 64 tpi starting threads The blue lines show where the threads are in opposition and the red lines where they coincide.

Finally, either start with a screw as close to the length you wish or start with enough excess thread so you will be back in coincidence at your desired final length.

Bob

 

[savarin]

I have used a good quality die for a series (in excess of 20) of 4mm threads in stainless, the die is now blunt.

 

[darita]

Thanks...duely noted...

 

[Andre]

Do what you gotta do, that's what it always comes down to in the end. I bet it will last just fine, especially if it's an adjustable round die and you take light cuts per pass. (cut, adjust, cut, adjust, etc)

 

[rick9345]

Is it harmful to a HSS die to use it on a stainless steel blank? It's a very small die, 1-56, so I don't want to damage it. Thanks.

A little unsalted bacon grease or Crisco lard for tapping/threading on SS helps