getting a die to cut

[steamer]

Zee,

I think Frank McClean had a nice die holder/tapping head in one of his books put out by Villiage Press

They are truly worth the effort to make, and give you some pride and experience.

I'll snag a photo of my rig when I can....and poke around and see if I have an article

I think Littlemachineshop.com has them for sale too.

http://www.littlemachineshop.com/products/product_view.php?ProductID=2314&category=1

They appear to be on back order though.

Dave

 

[zeeprogrammer]

Robert: Amazingly I found an 8-32 bolt in my meager supplies. It fit - just. That might make one question if I turned the right diameter but I've checked it often enough to feel confident. I'm thinking it's a bum die. In any case, I should/need/want the proper 'good' tool as advised by the knowledgeable ones here. I'm going to wait until I get them (the dies) and not modify the part until then. Then I should be able to tell where the problem is.

It's a good thought though. Reminds me of the story where a two bay rocket was sent up with a satellite in one bay. Mechanical and software guys were told bay number 1. Mechanical counted 1, 2. Software counted 0, 1. Right number. Mechies just can't count. ;D (And you Pascal people can just keep quiet. It's 'C' for me and I still miss DOS.)

Dave: Thanks. That's the holder I have. I didn't realize at first that it took two sizes. Didn't matter though. You can't fit a hex shape into a round hole.

 

[websterz]

You can't fit a hex shape into a round hole.

Sure you can, but it won't have much contact area. :big:

 

[tmuir]

Marv: Thanks very much for the explanation of how to use split dies. Very very helpful. I thought the idea of using the holder's screws to squeeze in interesting too.

There is another type of split die.
The one with the screw I believe is the common one in the US.
In the UK and OZ (and probably esle where) they have a split but no screw. The 3 screws in the die holder are used to compress the die closed more rather than a screw to open it. Both do the same thing just different ways.

 

[ozzie46]

Use a "cheapie" 3/8 or 1/2 drive socket to fit hex die cut short to fit in round bore . Drill thru die holder into socket for holding screws/bolts to keep socket in the holder and keep it from turning in holder.

The reason for "cheapie socket" is they are usually softer than quality sockets and easier to drill. ;D


Ron

 

[mklotz]

Zee wrote:

You can't fit a hex shape into a round hole.

You can if the diameter of the hole is equal to the diameter of the circle that circumscribes the hex.

Marv wrote (reply #16):

Also, if you have hex dies, you can make the counterbore large enough to accept them and then prevent them from rotating with a couple of axial set screws. There's no need to broach or otherwise construct a hex-shaped hole.

 

[zeeprogrammer]

You can't fit a hex shape into a round hole.

I just knew some of you couldn't resist.

Marv: Elegant way of saying...'if the hole is big enough (and yet not too big)'.
I can call you elegant...can't I? ;D

Thanks all.

 

[Foozer]

You can't fit a hex shape into a round hole.

I have this 30 ton log splitter that . . . well I couldn't resist it

 

[radfordc]

Also, I agree with Marv - don't do the tapping under power, unless you are _very_ confident that you can stop the machine _VERY quickly_ if something goes wrong.

Mainer's picture of his die holder shows that it is hand held only. When tapping under power if something gets stuck you just let the die holder spin freely.

However, I still don't tap under power....I hate trying to get broken taps out!

Charlie

 

[substandard]

I have this 30 ton log splitter that . . . well I couldn't resist it

It is a fact that you can put a .406" round punch into a .25" square die with 30 tons of pressure, at least once. I proved that the while running a CNC punch press.

Here in the USA I buy Irwin-Hanson taps/dies. The Chinese set I got off of Ebay provided some interesting looking threads. Since then I stick with a quality maunfacturer.

 

[Mainer]

You've got it, Charlie. All I have to do is let go, and at 60 rpm in slowest backgear it's not a problem.

If the die holder couldn't spin freely, however -- if it had a bar to provide more leverage, or something -- I wouldn't attempt cutting a thread under power.

And I have yet to tap a thread under power.