# Using adjustable dies?



## Cap'nBill (Dec 27, 2008)

I purchased some Hanson 'adjustable' dies to thread some 3/32's stainless steel rod. I use a dieholder held in the tailstock chuck. I found some 'quality import ' dies were'nt up to the SS. Now the question: what is the correct way to use 'adjustable', seems the screw is very difficult to move and can't see difference. Bill


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## Semper Vaporo (Jan 2, 2008)

I don't think you will be able to "SEE" a difference from min to max cutting depth in the adjustment, but you will "FEEL" it in the end product when you put a nut on the threaded rod. 

As to the 'correct way'... I hope someone will give an answer to that question. I have some cheap adjustable dies and I have just opened them to the max they will open to when in the holder, thread the rod and try a nut. if it won't fit as well as I want then I tighten the adjusting screw and re-thread over the rod and try it again. I usually only cut a small section at a time working at it until I get the desired depth and then cut the whole threaded area. If the item I am making is too short to do it that way, then I work on a scrap piece to get the depth, then I cut the deisred end product. Depending on the material, I feel the re-cuts at smaller diameters seems to just garf up the threads that were made last time, leaving a rough surface to the sides. 

I'd recommend LOTS OF cutting oil when cutting stainless. If you have good dies, it will cut wonderfully, once it gets a good bite. 

What thread pitch are you cutting?


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## Kovacjr (Jan 2, 2008)

I had another die that was cutting too deep and was one of the adjustable ones and it was not really adjustable within spec and snapped. It was the last Apex brand die I bought. 

As to the adjustability of the dies you only ger a few thou of adjustment. The dies are supposed to be in spec when you purchase them. Ive used the Hanson brand and never had to adjust. I also use both a die handle and a tailstock holder, both without problems. What thread are you threading?


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## xo18thfa (Jan 2, 2008)

Most of my adjustable threading dies are actually just split. Like this










No screws to hold the adjustment. If you put them in the die stock and engage to little drive dimple on the side, you will crush them and get a very loose thread. I sharpened the grub screw on the die stock a little bit and run it into the split. You can actually spread them just "TT" enough to get a tighter fitting thread. After a while you just "feel" it and they will cut good threads.

The dies I have with screws do fine, but I still run the grub screw into the split.

Stainless steel comes in many alloys. Alloy #303 is free machining and threads very well. Use cutting oil. Other alloys range from difficult to down right nasty.

And BTW, don't buy cheap dies. Get quality dies from the industrial supply houses like McMaster Car, MSC Direct or Traver's Tool. McMaster Carr's "imports" usually come from Japan and are very good.


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## Cap'nBill (Dec 27, 2008)

I am threading, for the purpose of this question, 2-56. For steam cylinders, linkage, etc., I use the threads 0f 00-90, 0-80, 1-72, and 2-56. I typically use brass hex head bolts from Micro-fasteners which I buy by the 100 pack. With the 3/32 SS, I use a smallish, sharp point to turn the stock down at about .002 per pass to get a good start. I guess the best way is to turn your stock down to the matching diameter of the drill bit one would use for the tap. I have mostly K & S taps, however, it is noted these are for brass and aluminum. I have just noted the adjustable die screws seem almost impossible to adjust with the small screwdriver. I think the tap holder grub screws probably apply as much pressure. Indeed, cheap dies just don't work on SS. When new, the Hanson's peel off a nice little 'curl'. Bill


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## Chris Scott (Jan 2, 2008)

Drills Taps and Dies (Workshop Practice Series Number 12) [Paperback) by Turbal Cain 
His series of books are excellent shop reference. 

http://www.amazon.com/Drills-Worksh...d=1341775308&sr=8-16&keywords=TAp+&+die+books


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## Kovacjr (Jan 2, 2008)

Bill, 

Here is a chart to follow http://www.engineershandbook.com/Tables/threadlimits.htm 

From the charts I have 0.112 would be the dia needed to thread 4-40. So a 3/32 rod would be too small as its 0.093 

I try to use 5-40 for piston rods and such as its threaded straight from a 0.125 rod. 

Also I use MSC for all my tap and dies. All the imports are from japan and are just as good as the non import. Id stay away from the chinese dies if you see any.


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## xo18thfa (Jan 2, 2008)

Posted By Kovacjr on 08 Jul 2012 03:13 PM 
Bill, 



Also I use MSC for all my tap and dies. 
MSC has a warehouse in Nevada, so sales tax AND shipping. grrrrrrrr!!


They have very good prices, high quality and about the widest variety available. IF MSC does not have the size you need, they are probably not available anywhere.


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