Drilling Tahitian Pearls

[Stella'sStones]

hi, first time poster!

I have recently purchased a pearl drill, Japanese with a swivel holder, and have been attempting to drill my own pearls for design. I have have run into a couple of problems.

1. Some times I try to drill a pearl and it is like trying to drill a rock. If I force it the bit typically breaks. What am I doing wrong?

2. If I am drilling the pearls for a necklace, what size bit should I use?

3. Some times (with the larger pearls), I cannot get the swivel to spin without retracting the bit. I am worried that this may misalign the holes. Is there something I am missing?

Thanks guys!

[jshepherd]

Welcome to the forum!

Those Japanese drills can be a little tricky as the instructions (if there are any even included) are nearly incomprehensible. In answer to your questions:

1. Some times I try to drill a pearl and it is like trying to drill a rock. If I force it the bit typically breaks. What am I doing wrong?

I know what kind of pearl you are referring to. I am not sure why this happens at times. I have broken pearls open in the past that were hard as rock just to examine the nucleus, but I have not found a difference. Some are just extremely hard.
There is a way, however, to get through these pearls. If the bit breaks the pearl is lost, so you should never force it through. Try using a tapping motion and do not go more than 1/2 through each side. If you tap very lightly you will eventually make it through the pearl and the bit will not break. But the bit will be completely dull when you are finished. Not a bad trade off, however, a $3 bit for a good Tahitian pearl.

2. If I am drilling the pearls for a necklace, what size bit should I use?

I like to use a .7. You can go larger for larger pearls, but I would stay away from anything smaller. The smaller bits tend to bend within the pearls, and the thinner silk thread with stretch more quickly with the heavy pearls. One thing is important to remember - always drill the last 2 pearls on each side one size larger so that the stringer will be able to wrap the thread back through.

3. Some times (with the larger pearls), I cannot get the swivel to spin without retracting the bit. I am worried that this may misalign the holes. Is there something I am missing?

You are using the wrong size cup for the pearls you are drilling. If you are drilling a 15mm pearl you need to use a cup that is at least a size 13 or 14. Although a 9 will seem to work, the swivel width will then be too big to spin.

Good luck!

[PearlsAndJade.com]

Thanks for posting that information about the drill operation. I'm in the process of purchasing one and your post was very timely for me.

Bill

[jshepherd]

Noi problem. A&A in Los Angeles carries a good one. We have purchased 2 from them in the last year. THey are $1000 each, but very well built.

[PearlsAndJade.com]

Noi problem. A&A in Los Angeles carries a good one. We have purchased 2 from them in the last year. THey are $1000 each, but very well built.

Thanks Jeremy. What is the full name of the company? I can't find a web site for them.

Bill

[jshepherd]

http://www.aajewelry.com/
The Website is not functional. But I do not even see what purpose it will service with the size of the supply company. They have several floors of goods and the photography alone would probably take a year. Also, everyone knows most jewelers do not use the Internet...

A&A Jewelry Supply
319 W. Sixth St.
Los Angeles, CA 90014
T: (213) 627-8004
F: (213) 627-1653
e-mail: orders@AAJewelry.com

[Stella'sStones]

PERFECT! Thank you so much. I wish I had posted here a month ago. You would not believe how many jewelers I have asked these questions to! None of them have been able to answer me!
I really appreciate your help. Today I drilled those rock-hard pearls that I had saved so a jeweler could try a diamond drill. It works just like you said! I am also going to buy more cups tomorrow.

[Stella'sStones]

Jshepherd

Quick price quote question:

A dark color (green perferably) lot of 10-11mm, round (not near round), A quality (clean) Tahitians. I am thinking about 100-120 pearls.

Thanks!

[jshepherd]

For a color selected lot of that quality (basically the highest), you are looking at about $80 per pearl. This is selection price, and entire A lot (mixed darks) would be less.

[PearlsAndJade.com]

Thanks Jeremy,

I'll call them,

Bill

[Stella'sStones]

I am back with another quick question Jeremy. I am still breaking a lot of drill bits. They just tend to snap sometimes, even on pearls that are not too hard. Any thoughts?

[jshepherd]

Do the bits break in either direction or almost only on the reverse side?

[Stella'sStones]

Just on the reverse side. The tip comes off and gets lodged in the pearl. It is impossible to get out. I have tried changing bits more often but it does not seem to make a difference. I just feel like I am still missing something.

[jshepherd]

The trick is to drill more than 50% on the initial hole. When I drill I push until I feel the nucleus/conchiolin layer. You have to be very careful and release pressure as soon as you feel the separation, otherwise you will go through the nacre. Then, when you switch sides you will only have about 2mm to drill.

If you are not comfortable drilling this way just try to drill at least 3/4 way through the pearl. The less you have to drill on the reverse the smaller the chance of breakage. But, if your bit starts to angle on the first hole do not go more than half, and drill from the other side slowly and carefully.

[Zeide Erskine]

Hi Stella,

I was wondering for awhile why you had this drilling problem and clam nuclei did not sound right for the rocky bit of your probem.

hi, first time poster!

I have recently purchased a pearl drill, Japanese with a swivel holder, and have been attempting to drill my own pearls for design. I have have run into a couple of problems.

1. Some times I try to drill a pearl and it is like trying to drill a rock. If I force it the bit typically breaks. What am I doing wrong?

2. If I am drilling the pearls for a necklace, what size bit should I use?

3. Some times (with the larger pearls), I cannot get the swivel to spin without retracting the bit. I am worried that this may misalign the holes. Is there something I am missing?

You may want to read this: http://www.spc.int/coastfish/News/POIB/13/POIB13-6.htm That seems to get to the heart of the matter.

Zeide

Thanks guys!