Tapping earring post

Hello,

I already have a tap and die for earrings but the thread is too
tight and involves too much winding. Whenever I have a request for
these I don’t make them, I buy them. I can’t find what I need
locally.

Does anybody have a good supplier for tap and dies that have a loose
thread?

It seems to me that 3-4 turns should do it and a heavy thread is
better then fine.

Sorry for the complete lack of proper technical jargon. Hope it
makes sense.

Add I’d like to start afresh with ALL my stamps (Plat, Pt, Pd, 750,
etc in 2 sizes). Does anybody know a good stamp maker who uses good
quality heavy stock? It is important to me that they are all the
same weight, and the heavier the better.

Phillip

Phillip,

When creating a loose thread from tapping use a larger drill bit.

From Morse Cutting Tool’s “Machinist’s Practical Guide”:

Example: screw size #0-80
Body drill: 52

Size or number of drill for percent of full thread
100% tap drill: 58
80% tap drill: 57
75% tap drill: 56
70% tap drill: 56
60% tap drill: 3/64"
50% tap drill: 3/64"

Interesting notes:

“A 53% thread will break the bolt, before it will strip - in most
cases.”

“A 100% thread is only 5% stronger than a 75% thread, but it requires
three times the power to tap.”

Most of the work I do (steel, ss, polymer, aluminum prototyping) is
cut at 75% full thread. I might index one drill bit size larger than
recommended if I’m in a hurry on non-critical stuff.

Off list I can give you the drill bit numbers for the taps you are
working with. For very thin stock, you will want to use 100% full
thread, whereas the above is for holes as deep as the diameter of the
tap.

Jeff Simkins
http://blackicepond.deviantart.com

Off list I can give you the drill bit numbers for the taps you are
working with. For very thin stock, you will want to use 100% full
thread, whereas the above is for holes as deep as the diameter of
the tap. 

That went over my head, sorry. I don’t understand what the
percentage scores relate to.

I only need one size of tap & die, which is for 0.8mm wire. For me I
think a range from 0.5mm to 1mm would be usefull if I get the time
to use them in a design.

I’ll appologise in advance for a total memory block on the
appropriate technical term - the few I know.

The depth of the cut on the die is important as much as the thread
should be fairly deep. What is more important is how close the
threads are spaced. It needs to be long. The main metals would be
750 gold and plat, so I can get a lot of turn fast. The tapping side
of things is simple enough. I only need to tap into a soft metal
4mm’s tops.

I imagine I would struggle with the smaller ones. I did in the past,
but if I do one I will do a hundred, so I am sure I will sort out
the right drill size pretty quick.

The tapping sets I see around are probably not made with jewellery
metals in mind. The best sets are available. I know because you can
buy earring posts with the threads just right. The problem is that
the butterflys/scrols are often too expensive for what they are. They
are easy to make and if you can make one by hand cheaper then you can
personalise it at the same time. They come out nicely.

Phillip,

If this source hasn’t already been suggested, Reactive Metals,
http://www.reactivemetals.com carries a nice range of tap and die
sets and you might find there what you are looking for.

Susan Ronan
Coronado, CA