Colibri Precious Metal Tap and Die- help needed

Jewelry Discussion
1

I am befuddled by this tap and die set. The dies and taps show .6, .8, 1, 1.2, 1.4, 1.6, 1.8 and 2 mm sizes. No instructions for this set, or any for taps and dies less than 1mm anywhere I have looked. This set was darned expensive and I would like to be able to use it.

When I use .81 argentium wire pulled down to .75 mm - taper the feed end at about a 30 degree angle and try to turn it, with a pin vice, into the .8mm die with cutting oil- it just chews the crap out of it (I know a real technical term.) The die also has 4- .8 mm holes - 2 with slots and 2 without- no indication if these are just redundant or are like that for a purpose.

Strangely, the .75mm wire will feed and cut visible threads in the 1 mm die- hard to image that is possible if the outer dimension of the 1 mm die is 1 mm (which is max diameter correct?) I assume that it is the thread cutting depth of the die that extends beyond .25 mm in the 1 mm hole that result in raised threads on the .75mm rod (wire.)

If anyone is using this set effectively or has an idea of how I am screwing this up or in what way I have it wrong- I would appreciate some help.

I’ve read that the drilled hole for the tap should be about 60 to 75% of the tap size. A 1mm tap would work with a .75 mm drill hole (actually a range between .6 and .75 mm.) I thought that the rod size for a 1mm die was suppose to be 1mm (the max diameter) but given that I couldn’t get a .75mm argentium wire to start and cut cleanly in a .8 mm die I have to question that.

Also, am I incorrect in assuming that I can cut these by hand- with the tap in a pin vice - carefully twisting it in to the drilled hole in the metal; and with the rod in a pin vice rotating it into the die (quarter turn etc, etc.)

Looking for a lot of good information on this- hope you can help.

Kirk

2

The holes with slots are for cutting new screws. The slots are what make the threads of the hole into cutting teeth. They also help clear the chips.
The holes without slots can be used for a finishing pass and also for rethreading damaged screws.
The drilled hole for tapping cannot be smaller than the minimum diameter of the tap. Taps and dies form the metal by cutting, not by swaging.
As to the diameter of wire for the dies, full diameter screws are made by rolling or single point turning. Threading with a die will always require the rod or wire to be slightly undersized, but 75% of the nominal diameter seems a bit too small. 90% of nominal diameter should be fine for these small sizes. Of course, getting the optimal diameter will depend on your drawplate.
Also, try making a longer taper on the wire, more like you might for drawing.
I’ve only used the commonly available, cheap screwplate, and that infrequently, mostly going by trial and error.

1 Like
3

Thanks Elliot, Good information. FYI - I’ve read in several places that even a 60 to 70 % rod to hole size works (and is easier to thread) and that 75% rod size has 95% of the holding capacity of a 90% rod size.

Are you successful doing these by hand with a pin vice?

4

As I recall I did hold the wire in a pin vise. I think it was the cheaper kind, which has corners that grip the wire, as opposed to the better ones with collets.

5

hi,

i have the economy tap and die set…

one thing i learned was to secure the thread cutting device/ or the piece to be threaded in a vise to keep it from moving

and a pin vise to secure the tap/ or wire to be threaded…

i held the piece to be threaded in my hand and easily snapped the tiny tap…

luckily economy replacement tap sets are available for under $10…2pc each size

julie

6

Thanks,

Yes- I snapped my first tap yesterday. Tried to get an extra 1/4 turn in a blind hole. Colibri charges $90 for a set of 18 and I already spent a bundle for the original taps and dies.

I have a ball vise with which I hold dies as well as the item to be tapped.

I am really puzzled why a 20 gauge wire (.81mm) even draw-plated to .75mm, won’t fit or feed into the .8 mm slot hole of the colibri set. I wonder if I need to anneal it before trying to cut threads on the die.

I am pretty sure it like everything else I learn in my studio - it seems impossible at first and after some trial and error and doing it isn’t. I look forward to getting there with this- I have a lot of cool ideas.

Kirk

| wldlzrd1
July 15 |

  • | - |

hi,

i have the economy tap and die set…

one thing i learned was to secure the thread cutting device/ or the piece to be threaded in a vise to keep it from moving

and a pin vise to secure the tap/ or wire to be threaded…

i held the piece to be threaded in my hand and easily snapped the tiny tap…

luckily economy replacement tap sets are available for under $10…2pc each size

julie

7

hi,

on another note…re: the numbers…

my die strip was numbered 7 thru 20
i did not equate that with .7mm thru 20mm…at the time​:grimacing::flushed::joy:

my taps were not numbered, so i spent s bit of time arranging them by size…with a loupe!…

then, not considering the significance of the numbers,

i took a test piece of the wire diameter i wanted to make a bolt with, dead soft i think…

and just eyeballed the die holes and twisted the wire into various die holes, looking for the right “feel”…

clipping off the end after each try, until it felt like it went in firmly and smoothly and produced nice looking threads…

then i gently tested various taps into that die until i found the right “fit”…

then i put a sharpie mark on that particular tap and die
and proceeded to make the nut hole…

after staring at the set, and the sharpie markers, and revisiting the link where i bought it to see if sizes were listed…

the mm size association with the numbers finally dawned on me (omg) and i marked my box…

i will say that my choices for tap and die were not corresponding…ie: the die was 10 and the tap was 9 in the tap lineup…(or visa versa…i forget)…i think my wire was .80mm

sooo, to make a long story longer…pick either your bolt or nut hole size, and test by feel…

i hope i made some sense…

julie

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…i think i associated the numbers as being like those on drawplates…not indicative of size measurements…

julie

9

hi,

it might be worth $10 to see if one of the economy replacement taps in this 28pc set (2 each size) can replace the tap that broke…

julie

10

Apologies, I don’t have specific directions for your brand of tap-&-die set, but here are some instructions I downloaded back in 2011. Hope it helps…

Tap & Die Instructions

How To Create Threaded Connections Using A Tap and Die Set

Working with small connections, it is important to be able to cut precision interior and exterior threading. Use Bur-life or blade lubricant.

The screw-plate is a threading die for hand-forming external threads on screws and bolts. The plate is highly tempered tool-steel, pierced with one or more threaded holes—progressively increasing in size—that are circular or double-notched for the clearance of metal chips.

The taps are very much like drills, also progressively increasing in size, each corresponding to one of the the die sizes.

We strongly recommend using liquid BurLife® for all tap & die work.

1 Create An External Thread (Die):

Select the die on the screw-plate with an inner thread diameter slightly less than the diameter of the shank that you wish to thread, so that it will cut into the shank and form threads.

2 Clamp the head of the shank in a vise with the shank pointing perpendicularly upward.

3 Turn the plate over and set the selected die firmly over the shank to fix it in a starting position. Please Note: The screw plate is designed to work front to back. With the shank held upright in your vise, the plate must be turned over to allow the shank to advance through the plate from front to back.

4 Turn the screw-plate clockwise; the grooves in the screw-plate begin cutting into the shank as the screw-plate advances.

5 Continue to wind the screw-plate until the desired depth of thread is formed on the shank, then reverse the direction and unwind the screw-plate until it can be removed.

6 To Create An Internal Thread (Tap):

To create a nut or threaded hole for use with a screw or bolt, cut a rectangular piece of sheet metal thick enough to engage at least three of the thread crests on the screw or bolt (or allow for such thickness in your base piece). Please Note: At least three threads are needed to give the nut sufficient grip to hold the screw or bolt securely.

7 Mark the center of the sheet metal rectangle (or the desired position on the base piece) with a center punch.

8 Using a tap drill that corresponds with the tap size used, drill a hole straight through the metal where you have marked it.

9 Insert the tap , make a quarter turn, then back off.

10 Continue advancing the tap by quarter turns and backing off until the hole is completely tapped. Be sure to keep taps clean and free of shavings while tapping.

11 When the hole is complete, remove the tap from the hole.

Use Bur-life or blade lubricant [Renaissance Wax works well too]

11

hi…

“tap drill”…interesting! followed by tap…

i eyeballed and used a smaller dia twist drill…i need to get more technical …!

julie

12

Oil both the tap and dies. When using the tap, screw in a little, then reverse and start screwing again. I snapped one the first day, too. Since I adopted the oil and backing out method, no problems. Make sure that everything that can be held down is held down; the steadier the better. When I was tapping tubing I always had to sacrifice part of it that got crushed from securing it in a vise.

Mine wasn’t a cheap set, but it wasn’t as much as yours. But I got mine 10 or so years ago. Mine came with a holder for both the taps and dies. Mystery maker; no markings on the box or tools.