adjustable dye

[all thumbs]

When using an adjustable dye to create threads on a rod, are there any tips concerning how tight the screw should be set?

 

[ShopShoe]

all thumbs,

Are you cleaning up already-threaded rods or threading from a smooth rod?

I have been gradually replacing my fixed dies with adjustable ones and I have been playing with them as projects require their use. As in all operations, it easier to sneak up on a cut than try to do it all at once and overdo it. After all, you can't put metal back.

When I got my first adjustable die I ran it over an already threaded rod, then looked at the result carefully to see where it was cutting. ( A good magnifier helps.) then I tried putting dychem on the existing threads and adjusting the die slightly and going over the threads again and studying the result. After two or three of these learning exercises, I feel I know better how to adjust the die for the threads I am cutting. I have applied the same approach to improve my skills in center-pointing on the lathe.

--ShopShoe

 

[wheeltapper]

I always start the thread with the die wide open, then test for fit, and if necessary close up and cut again.
repeat till its a good fit in the matching thread.

Roy

 

[Blogwitch]

As Roy has stated, the centre screw should be tight in to begin with, but the other two outer ones should be tightened as well after the centre one has been set.

I use half a turn out for coarse adjustment on the centre screw until you nut fits but is still tight. Then it is about 1/8th of a turn on adjustment.

I always try to cut a runout slot first, purely because the nut won't run up to the end as the thread is actually tapered, hopefully the tapered part of the thread will sit over the runout slot and so the nut will screw all the way on.

A little trick if you don't want to put the runout slot in is to turn the die around after first cutting the thread to size, with the lettering on the back face. Make sure that the screw setting is exactly the same as when you finished cutting the tapered thread. This should then cut the thread up to a shoulder without being tapered and allow the nut to screw all the way on. Or use a thread file to cut the tapered part down a bit so that the nut runs to the end of the thread.


John

 

[gbritnell]

I use dies quite a bit for my model work. Most of them are small but I have dies up to 3/8, coarse and fine. The problem with a lot of the dies I use is that they cut too small so this requires that the adjusting screw, in the die, needs to be tightened to open up the die. Herein lies 2 problems. The first is that the screw is so small that using a screwdriver that fits won't provide enough torque to turn the screw. Second, most dies are so unflexible (high speed steel) that it's virtually impossible to use the screw to open them up. What I do is tap an old screwdriver, tapered blade, into the slot and this will aid in opening up the die. Now the screw can be turned to hold it in place. From there it's a matter of readjusting until you get a good fitting thread.
As a side note I use 0-80 dies quite a bit. I can't tell you how many 'import' dies I have purchased that just won't cut so I thought I would go all out and buy an American 0-80 die. On top of being much more expensive they weren't any better than the imports. It seems like the small die supply is a very hit and miss proposition.
gbritnell

 

[wheeltapper]

What i did with mine was threw the screws away and fitted socket head grub screws.
It's much easier to tighten up with an allen key and you can't slip and dig the screwdriver into your hand.

Roy.

 

[GailInNM]

As a side note I use 0-80 dies quite a bit. I can't tell you how many 'import' dies I have purchased that just won't cut so I thought I would go all out and buy an American 0-80 die. On top of being much more expensive they weren't any better than the imports. It seems like the small die supply is a very hit and miss proposition.
gbritnell

George,
I have been through much grief finding 0-80 dies of any decent quality. 00-90 are even worse. I had gotten to the point that if I was making up an order I would order a die from almost any supplier that I had not ordered one from before.

About 6 or 8 years ago while I did this with Micro Mark not expecting much. I ordered 0-80 die and to my astonishment it worked very well. So I ordered a 00-90 and it also worked well. Much better than the name brands that I had tried.

Now I have no idea if what they are selling now are any good, after all it has been quite a while, but you might try one of theirs if you are ordering any thing else from them.

Gail In NM

 

[mklotz]

My experience matches Gail's. Unfortunately, like Gail, I ordered mine a number of years ago so I cannot vouch for what one might receive today.

 

[kwoodhands]

I use dies quite a bit for my model work. Most of them are small but I have dies up to 3/8, coarse and fine. The problem with a lot of the dies I use is that they cut too small so this requires that the adjusting screw, in the die, needs to be tightened to open up the die. Herein lies 2 problems. The first is that the screw is so small that using a screwdriver that fits won't provide enough torque to turn the screw. Second, most dies are so unflexible (high speed steel) that it's virtually impossible to use the screw to open them up. What I do is tap an old screwdriver, tapered blade, into the slot and this will aid in opening up the die. Now the screw can be turned to hold it in place. From there it's a matter of readjusting until you get a good fitting thread.
As a side note I use 0-80 dies quite a bit. I can't tell you how many 'import' dies I have purchased that just won't cut so I thought I would go all out and buy an American 0-80 die. On top of being much more expensive they weren't any better than the imports. It seems like the small die supply is a very hit and miss proposition.
gbritnell

I only use Cleveland dies in the small sizes.They are American made. Though I have to admit I stopped using 0-80 screws where ever possible. I do much better with 1-64.
When I broke the last 0-80 tap I had I decided to work around this size if possible.
mike

 

[rake60]

An adjustable dies intended purpose is to achieve various thread fits.

A Class 1A external and 1B internal fit thread can almost be thrown together from across the room.

A Class 3A external with a 3B internal fit takes a bit of effort to assemble but it won't loosen up easily.

Class 2 is between 1 and 3.

And then there is Class 5.
It is an interference fit that causes both the internal and external thread to deform during assembly.
It's difficult to screw together and you hope someone other than you gets the job of taking it apart in the future.
That usually results in a broken bolt or stud followed by an outburst of language unknown to most civilized nations.


Rick

 

[hobby]

Though I have to admit I stopped using 0-80 screws where ever possible. I do much better with 1-64.
When I broke the last 0-80 tap I had I decided to work around this size if possible.
mike

If I need a 0-80 threaded rod, sometimes I use the die, from my set from, micromark, but most of the time I can get away with tapping a hole 0-80 into the workpiece, and loctite a 0-80 screw into it, and cutting of the head of the screw.