First time using a die failure...

[DigitalM]

I'm trying to buy (car boot) and restore a complete set of Stanley hand planes, and as part of this bought a 12/20 tap and die set so I could make my own handle bolts etc.

Before anyone says it, yes, I know, rather than make your own you can buy them on ebay for what looks like a reasonable price, but where's the adventure and learning in that.

So, having purchased some 13/64" rod (as quoted on quite a few Stanley sites) I set about watching half a dozen "How to use a tap and die" videos on youtube and had a try myself ... and failed to get much more than a mm or so onto the rod (stop laughing at the back, at least I'm trying!).

The rod is 13/64" BS1407 silver steel, and the die is part number RD-12-20-B, #12-20 HSS Special Die, 1" OD HSS from victornet.com - from what I can tell, both sides of the die (marked and plain) have a very slightly flared opening for starting a thread.

I've filed the top to the rod to have about 2mm 45 degree chamfer on one end, tightened it in a vice and done what everyone seems to be doing in the videos, but can never quite get far enough for the thread to catch.

Maybe I've already said enough and someone can point out what I'm doing wrong, I don't know?

Is silver steel the wrong stuff? Maybe I've misinterpreted the die and rod sizes.

Anyway, there we go. Does anyone have any idea what is leading to such pathetic failure?! As I said, I'm no metalworker so please go easy on me - at least I'm having a go, eh?

 

[porker]

Silver steel should be OK assuming it is still in its annealed state and you haven't hardened it already. I assume your die isn't split which allows you to start 'opened up'? If you have a drill press it might be helpful to use this to start the die square to the rod. Difficult to explain but there should be some videos on line showing this. Use some cutting oil if you have some as this also helps. I also understand the ends of silver steel rods can sometimes be a little hard due to the cutting process so might be worth cutting a little off the end but putting a chamfer like you are doing is the right thing to do and your OD looks right on the rod. HSS dies should be OK but I must admit I've had a couple that were difficult to start.

 

[DigitalM]

Yeah the die is split and I've adjusted it wider to see if that helped.

I'll try cutting a bit off the end of the rod and see if that helps.

I take it that some dies do have the starter flare (sorry, don't know the term?) both ends and I'm not just misinterpreting that?

 

[Limey Lurker]

You need to put some downward pressure on the die. Start with "some" pressure. and keep increasing the pressure until the die starts to cut.

 

[porker]

The lead in is usually on the side with the markings but not always.

 

[t8hants]

dies shouldn't have flare on both sides as the idea is the thread will get deeper as your cut progresses.
Normal practice should be that the flare is on the same side as the size and maker are stamped, allowing you to pick it up whilst still in the holder and know what you have got.
hand threading takes a bit of practice, why not have a trial go on something else before you tackle the job. 13/64th is a fat 5mm so you should be able to find something to practice on.
Also give yourself a longer taper to get started on, you are not going to see it when the thread is cut or you can cut it off when the thread is completed, if you cut a bit longer.

 

[Hemsby]

Years ago Silver Steel was cut to length in the factory using an elastic cutting wheels which could cause toughening at the ends, it was always good practice to remove about ½ inch.

Cutting oil is absolutely essential for Silver steel. Also a good taper on the steel to allow the die taper to get a start.

By design Silver Steel is a tough material, so perhaps not the best material to “practice“ on.

Another point, some lesser quality die holders do not have enough clearance to allow the die to open sufficiently to take the first cut.

 

[DigitalM]

Thanks info everyone. I think part of the problem is that I'm not using a manly enough vice, I hadn't noticed at first but the rod is turning sometimes, probably just at the point of max cut and undermining my efforts. I'll try again in a few days at my mates workshop.

 

[sunnybob]

Make sure you back the die off regularly. turn it half a turn in and a quarter turn out, as soon as it starts to cut. Lots of lubricant too.

 

[oakmitre]

As a side note, this is how I cut my steel rod to length. I find it to be much better than using a vice (no marring) , and stops any of those marks when the hacksaw blade skips around on the initial cutting.
Very light pressure with the saw blade to being with, once established it doesn't roll. The hacksaw causes no hardening or burr if you use light pressure only towards the end.

It's just a piece of whitewood with a hole drilled through the axis, and a saw kerf wherever you need it. If the rod is too short to hold, you may be able to drive a piece of rubber down a hole drilled in the top using a machine screw.

 

[oakmitre]

I haven't cut my keft 100% square in the wood above so the dowel is not square on the end, but below are the results.

There is a small fragile burr on the steel. I have a smoothing file clamped in the vice, and a piece of 220 paper clamp at the end of the bench nearby. I also have a tesco 5p scouring sponge.

To chamfer, I load it into my Aldi drill, put it on the faster speed and with (again) gentle pressure only, quickly pull it along the file for a about 10 strokes.I then do the same on the paper, and then move the dowel backwards and forwards in the sponge scourer bit. This gives a much better result than using a grinder and drill or filing round by hand.

If you lift the drill up as you pull along the file, it makes more of a domed top as shown in the picture. Again, there no effort being exerted in any of these steps.

 

[oakmitre]

And with a little bit of green paste on a paper towel (and an Aldi drill) the following can be achieved.