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Dennis
28-02-2011, 06:01 AM
Seamless tubing is very versatile, but its most common use is for mounting stones, taking it either straight from stock or more elegantly, made into tapered collets in a collet block. You need some practice to do this well. Another application is for making hinges and if the size of joint tubing available is not to your liking, you can thicken the walls by drawing down normal tubing, starting with about four sizes bigger than needed. As it comes in straight lengths, it can also be used as a light-weight rod, but it needs to remain vented to avoid trapping air or pickle.

Round tubing can be cut with a miniature tube cutter, from model makers’ suppliers, which uses sharp disks, but it does leave a slight constriction at the cut end and it is limited to the larger sizes.

The cutting jig favoured by jewellers has a deep groove in which to seat the tubing, a lever to hold it down and a slot to guide the saw blade. It can also be used for rod or strip. The handle may be clamped in a vice, or held in the notch of a bench peg. Once you have decided on a size of saw blade convenient for you, for instance 3/0, you can unscrew the outer plate and rub down the spacers so that the saw will fit into the slot more snugly and make a straighter cut. It also helps to tension the blade well. The stem of the length stop can be customised by marking it at intervals with saw cuts.

As the outer plate of the device is made of hardened metal it can be treated as a filing block for trueing ends, but the real tool for this is the Bergeon chenier clamp. It is expensive and must be regarded as a luxury item, but it will allow you to file the ends of tube rod or strip to a perfect right angle, or to 45 degrees. It is also good for holding strip and wire when cutting and filing a V-shaped groove and for holding tubing to prepare it for stone setting.

By feeding in copper wire, stripped electrical cable, or flex that fits, round tubing can be bent on a mandrel or wire bending jig without collapsing. The wire is then extracted by pulling it back-to-front through a hole in the face of a drawplate, which will hold back the tube. My main reason for doing this is to make supporting bails for pendants to fit thin snake chain, or cable. However after soldering on a jump ring, the inside often becomes too rough to introduce the chain. This can be dealt with by polishing with wet string and scouring powder. It also helps to file the end of snake chain to form a taper.

Below: Test tube pepper and salt set , pourers and upright made from round tubing.
Blue topaz and aqua pendant made from square tubing
Amethyst pendant with square tube decorations and round tube support.
The common tube cutting jig and the Bergeon chenier clamp. Dennis.

ps_bond
28-02-2011, 12:03 PM
I do tend to oil wire before inserting it into tube & bending (or drawing it down) to make removal easier; those working with gold tube have the dubious luxury of being able to etch out copper wire with nitric acid.

Being able to make your own tubing is useful - in this case, seamed rather than seamless - all it requires is a suitable drawplate (and ideally a small swage block to start it off).

I do like those pieces Dennis - particularly the salt & pepper set; the use of test tubes is excellent.

Kwant
28-02-2011, 02:42 PM
I have only thus far used tube as is for setting small stones and have been pleased with the result. I very much like the topaz piece Dennis, is it cable you have used to suspend it from?

medusa
28-02-2011, 05:26 PM
oooh! the topaz pendant is beautiful! it looks like there's a golden mean thing going on.

are you going to do rods? I'm guessing they aren't the same as tubes in terms of how they bend etc.

Tabby66
28-02-2011, 08:46 PM
Thanks Dennis for your descriptions for how the chenier clamp can be used. I received one for christmas and haven't made very good use of it so far!

Dennis
01-03-2011, 04:55 AM
Thank you for your replies,

1. I had been visiting Glasgow, so it's a touch of Charles Rennie Mackintosh.
2. Yes it's silver cable, I like coloured tiger tail too.
3. Rod is solid, but bends like wire. At the time I shopped at Blundells in Wardour street and they didn't list it. Now I would just anneal wire and stretch it on my draw bench. the effect is quite dramatic. Dennis.

medusa
01-03-2011, 03:10 PM
it does have a Glasgow School look to it!

I was thinking fatter rods, say 8-10mm diameter.

Dennis
01-03-2011, 08:57 PM
I was thinking fatter rods, say 8-10mm diameter.

O.K. Moneybags!

Joe
01-03-2011, 09:12 PM
Heh! You could make a whole piece out of one of Medusa's sprue-offcuts!

I did not think the price of silver would influence my sizing decisions... The world is mad!

medusa
01-03-2011, 09:32 PM
O.K. Moneybags!
I only said I was thinking of it!

Heh! You could make a whole piece out of one of Medusa's sprue-offcuts!

I did not think the price of silver would influence my sizing decisions... The world is mad!

my sprue pot weighs almost as much as my larger bangle :)

Inanegal
29-03-2011, 08:08 AM
Hi all,

Can anyone tell me whether I can draw down square tube in the same way as round tube?

I need some 1.5mm square silver tube, but most suppliers only seem to go down to about 2.25mm. Am I being too ambitious in attempting to draw down tube this thin?

What shape of supporting wire would I need to put inside it while I'm drawing it down? Would round do, or should I use something square? (I don't really mind what shape the hole ends up being; roundish would be OK).

Any advice gratefully received,

Nina

Dennis
29-03-2011, 09:02 AM
Hi Nina, you don't need suppoting wire when drawing down tube, only when bending it to stop it collapsing. Just pinch about 10mm flat at one end and cut and file the resulting bulge until it will pass through the first hole of the draw plate.

1.Keep the end well tapered before each pass, or the bit you grip will snap off.
2.Anneal after about 3 holes.
3.If youn can borrow the use of a draw bench for this the result will be more even and less curved.

Hope it goes well, Dennis.

Inanegal
29-03-2011, 09:49 AM
Thanks, Dennis - I'll give it a try!

Nina

Kitchenjeweller
11-04-2011, 12:47 PM
Here is great tip how to coil tube: http://davidcruickshank.ganoksin.com/blogs/2010/01/26/coiling-tube-useing-the-draw-bench/

Sandra
20-03-2014, 11:20 AM
Dennis do you still have the pictures from this thread? I don't see them here, I was interested in seeing the bail made of tubing in particular.

Dennis
20-03-2014, 07:35 PM
Well Sandra,

It's a really sad story, because one day I found all my uploaded pictures, in a list here and thought I could save space by deleting it. I never dreamed that it would delete all my pictures to date. The Devil makes work for idle hands.

As you will see from today's posts, I am unable to upload any more pictures today, so for the moment there is only this year's album to look at, using the link below.

Dennis.

ShinyLauren
21-03-2014, 06:48 PM
That's a bummer Dennis - I've not seen this thread before and would love to see the pictures!

Also intrigued by modification of the tube jig you described. I have one of these: [URL="http://www.cooksongold.com/Jewellery-Tools/Special-Joint-Filing-Tool----------Chenier-Cutter-prcode-999-597"] and I find the slot far too wide and can never get a straight cut, thus defeating its entire purpose.

Dennis
21-03-2014, 09:35 PM
Yes Lauren, the better the saw blade fits the slot, the straighter the cut will be. So:

You can select a saw blade fat enough to fit, but still move, or

You can undo the screws at the front, to reveal that the space is determined by metal washers, or sometimes a thin metal plate. Rub these/this down on flat sandpaper to match the sawblade of your choice.

All you need in addition is some calipers. I have also restored the pix as requested and one extra for good luck. Dennis.

Sandra
22-03-2014, 09:03 PM
Thank you Dennis! I love your work, it's great inspiration! It helps to see the tube bail pics, looks like I may need another new tool. :">