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View Full Version : I Bought A Round Collet Plate (but there were no instructions).



Dennis
04-04-2011, 05:39 AM
As Peter explained in his thread ‘Instruction Manuals’, Many essential tools come without any helpful booklet, and unless you learned to use them as an apprentice, you will be left to fend for yourself.

Tapered collets are very attractive and will support a faceted stone without the need for a bearer. So here is one way to make them using a collet plate:

1. Select a tube with an outside diameter about 1.0mm smaller than the stone. Then try this tube into a hole about 3.0mm wider than the stone. The total length of tube needed will be twice its inserted depth. You have now established the hole to use and the length of tubing.


2. Cut off the tubing and anneal. Tubes are very vulnerable to fire scale, so you might paint it with flux, or a saturated solution of boracic acid in meths beforehand. Now place the tube over the smallest hole in the plate (to protect the tip of your punch) and inserting the punch, expand the tube gradually by tapping the punch with a hammer. Re- anneal if you feel much resistance.

3. Finally, when your collet is pretty well shaped using the punch alone, insert it into your chosen hole and wriggle the punch inside by hand to perfect it. Adjust the height to suit your stone, leaving only about 0.25mm to rub over and cut off any unwanted extension at the base. Then the collet can be mounted on a screw type mandrel and filed, sanded and polished using a Scotchbrite pad or micromesh while rotating it in your handpiece. Also by holding a file against the rotating edge it is easy to achieve a near perfect bevel.

4. To fit the collet to your ring shank, file the base with the same size round file, or abrasive paper wrapped around a mandrel.

Below:
The collet set, with a New collet and a brass rod to tap it out of the plate if it sticks.
Collet on screw mandrel using the hand piece as a lathe.
Finished ring with set CZ. Dennis

Tabby66
04-04-2011, 06:20 PM
Brilliant, thank you Dennis, this kind of information is really useful! Copied and pasted into wrd to begin my 'how to use it' manual.
Thank you.

Kwant
04-04-2011, 06:26 PM
Is fire scale such a big problem? I find no matter how much the silver discolours, after heating a few moments in my acid bath cleans it up with no problems, mind you I do tend to use it neat as it comes and don't dilute it.

medusa
04-04-2011, 09:03 PM
dumb question, how do you fix the collet onto the mandrel?

Dennis
05-04-2011, 02:53 AM
Is fire scale such a big problem? I find no matter how much the silver discolours, after heating a few moments in my acid bath cleans it up with no problems, mind you I do tend to use it neat as it comes and don't dilute it.

Dear Quant,
The Grey/black discolouration which appears on the surface of silver alloys when heated is largely composed of cuprous oxide and can be removed with sulphuric acid or safety pickle.

Firescale, which is cupric oxide runs deeper and is a more purple colour. It needs strong nitric acid to remove it chemically, but it can be disguised by repeated heating and normal pickling to deplete the surface copper. This effectively gives you an opaque layer of fine silver.

More commonly firescale is removed by filing and coarse abrasives. It becomes increasingly obvious as ugly patches, the more highly you polish. So for me it is not so serious a problem as I am generally content with a brushed or satin finish. See Tim McCreight, ‘The Complete Metalsmith’.
Regards, Dennis.

Dennis
05-04-2011, 06:46 AM
Hi Liz,

Here is the screw mandrel.You can pass the screw through the collet and tighten it. If The head of the screw turns out to be too lage, it can be reduced by the same metod, tightening it over a short piece of tubing as a spacer first. Dennis.

Lisa Quinn
05-04-2011, 08:48 AM
The tip for securing the collet to the mandrel is pure genius, thank you Dennis x

Dennis
05-04-2011, 02:38 PM
Thank you Lisa,
I once saw a tutorial by a man who tube-set small diamonds entirely in his handpiece, but this was about straight settings.

First he fitted the tube directly into a collet of his handpiece and then held burrs against it while it was rotating, to form the seat. Next he filed the outer bevel, stopped it to snap the stone in and set it with a burnisher while going round again. It only remained to cut off the completed setting by holding a saw against it while it rotated and go straight on to the next one.

Being heat proof he could then solder them all in place. My idea of a fun project. Kind regards, Dennis.

lilia
05-04-2011, 09:52 PM
This is very useful! I've had a collet block for several years now, but tried only once and needless to say failed :(|. Will get it out again this weekend and follow your instructions.:~:

Dennis
06-04-2011, 05:31 AM
Hi Lilia,
I do hope you can make my instructions work. My light bulb moment came when I realised that it was better to start the collet on top of the block rather than in it. but outcomes vary, so do let us know how you get on. Regards, Dennis.

Kermit
14-01-2015, 08:09 PM
Just want to say thank you to Dennis for posting this how to (a very long time ago!). I have just bought a collet plate and this was very helpful in my first experiment with it last night.

I think I need to buy some screw mandrels to hold it in place as trying to work on a tiny collet is quite hard but for my first attempt I'm not too discouraged. I made a few mistakes - main one was that I didn't allow enough tube length, but I'll try again and hopefully get better.

Now to go and play with my new doming set :)

Dennis
14-01-2015, 09:24 PM
Kermit...that's a name from the past. I hope you are well.

As you will have gathered the waste generated when the tube goes in too far, can be reduced by sitting the tube on the surface to start with.

Due to fiddling with my Forum settings, I accidentally deleted the accompanying pictures, so here they are restored, Dennis.

Patstone
15-01-2015, 05:38 AM
Do you buy the mandrel with a screw top or do you have to make it. Also how do you know what size screw to use.

Dennis
15-01-2015, 08:57 AM
Morning Pat,

No there is only one size and you buy them as standard: http://www.cooksongold.com/Jewellery-Tools/Screw-In-Top-Mandrel-For-Rubber----Wheels-Etc.-prcode-999-AET

Regards, Dennis.

Patstone
16-01-2015, 07:52 AM
Hello Dennis,
I have a collet plate that I have only used once unsuccessfully I hasten to add. I also have a screw top mandrel but only use it for sandpaper discs. When you said you form the conical shape on top, do you mean not in the former, as in on the desk, then when the right size just use the former to perfect the shape. I wouldnt know what size tube to use either, so your previous post was helpful too. I dont set faceted stones very often as I cant seem to get the basket the right size or whatever you call it, I can however set flush, so tend to use smaller stones and do it that way. Thanks again for your help.

Kermit
16-01-2015, 02:37 PM
Thanks for the pictures Dennis - very helpful :) I'm going to have another go and see how far I get this time!

Yes, I have been absent for a while - I do try to read as much as possible even if not posting. In the last 3 years I've moved house, got divorced, moved house again, new partner, two deaths in the close family and my son being bitten by a dog and having to have surgery!! As a result I haven't been doing as much jewellery as I would have liked! But, new house has a space for a new jewellery bench (about to be built by my OH) so I'm really looking forward to increasing the amount I'm doing.

Nick martin
16-01-2015, 03:28 PM
Thanks for reposting those images Dennis, I've found them very useful too.

Nick

Kermit
22-01-2015, 08:10 PM
I've been trying to work out this Collet plate again, but not worked it out as yet.

I've attached a couple of images so you can see where I have got too.

Dennis - what is confusing me most is that it is not the same shape as in your photo's. Yours has a section of parallel tube and then the cone????

Would appreciate any suggestions.

thanks

Tabby66
22-01-2015, 08:49 PM
Hi Kermit,

That is because the tube used was longer than the tapered section of the collet block, therefore the excess tube gets pushed down beyond the taper. It is the tapered part that you need to be concerned with. I've attached a few pictures of some tapered collets 'in progress'....

727772787276

Dennis
22-01-2015, 10:13 PM
I've been trying to work out this Collet plate again, but not worked it out as yet.
I've attached a couple of images so you can see where I have got too.
Dennis - what is confusing me most is that it is not the same shape as in your photo's. Yours has a section of parallel tube and then the cone????
Would appreciate any suggestions.
thanks

Yes I think yours has the tapered shape going right to the bottom, so avoiding the tubular waste. That's good, but how to vary the technique would be a matter of experiment.

At a guess, I would begin by driving the tube in until it was just through the other side and file it flush.Then sit it on a steel block before inserting the tapered punch.

How big a tube to start with? Maybe half the maximum diameter and the whole depth of the plate. Go on until you are satisfied with the result. Dennis.

Kermit
22-01-2015, 10:21 PM
Thank you both, that is really helpful. I'll try again!

Paul Kay
30-05-2016, 10:11 AM
I know this is a fairly old thread, but, having just followed Dennis' instructions successfully, I would like to add my experience. The first collet was perfectly formed first time, and stuck firmly to the collet punch! I guess, because I didn't 'wiggle' the collet and punch in the hole to perfect it, but gave it a few good wacks. Heating (the punch sucked in all the heat), twisting with ridged pliers (nope), cutting (would probably have worked, but I was worried I may scar the punch) wouldn't budge it. Finally a firm grip and twist with some end cutters removed the now ruined (previously perfectly formed) collet.

Attempt #2; First I lubricated the punch (I used burr lube which was to hand, but I'm sure your favourite lube will work just as well) and did so at intervals while forming, and testing that collet was still removable. Second attempt perfect AND removable from the punch in that state.

Thank you for the original post Dennis, you definitely seem to have found the trick with the handy little tool, I'm now looking forward to spending much of the rest of the day experimenting with different sized tapered collets.

glitterandgem
30-05-2016, 10:13 AM
http://ganoksin.com/blog/larryseiger/2010/03/04/claw-setting-jig-review-and-tutorial/