Judy, first I seem to have seen smallish heavy walled tubing in
Hoover and strong’s catalogue…barring a custom order.
you can draw tubing, despite what anyone says, with well annealed
metal (. 999 silver or high karat golds work best) using a drawplate
*OR * a sturdy ( metal ) screw gauge - you don’t need a drawbench
for small lengths of tubing however it will have a seam that you can
easily close and clean up using successively finer grits of films,
discs, papers, etc. then finishing to the polish or texture of your
choice…but it is the easiest way to get a heavy wall and the exact
specs you need in a few hours. I have used this method many times
and it works well: starting with a tab on the length of metal you
wish to form to hold it fast in a pair of draw tongs or, if you don’t
have any tongs even pliers without smooth jaws will do. And as you
draw the metal ( annealing as needed as it work hardens) it will thin
somewhat, and the tool you use for your drawplate adds to the
differential as well: sapphire lined drawplates create the least
thinning, a basic screw gauge -the least thinning as it allows the
largest holes with which to form tubing.
I’m guessing you don’t want to make hinges with rolled tabs around a
wire or tube that you could then set with stones ( if it works with
your design) - but having a better idea of the hinge’s application
would be nice: if the hinge is very small, as though to make a pair
of earrings sway compared to that of a box lid or large pendant, or
consecutive bracelet elements there are many possibilities for the
best and longest wearing option should you 1) not be able to find a
ready made seamless mill product, or 2) you don’t want to make your
own that would require finishing to appear seamless…
Starting with larger tubing won’t work unless you have a drawplate
with the exact size o. d. end product you need and a length of piano
wire or other hardened metal wire that fits perfectly to maintain
the inner diameter you want to result in, which would require a
length of extra heavy walled tubing that can be drawn down that is at
least. 02-. 4mm larger than what you need the result to be- a hard to
do task at best…If by some miracle you have an extra heavy O. D.
walled tube, and a few successively smaller very hard insert wires
you could, in theory get what you want with a lot of stick type
lubricant - brass won’t work, and the smallest cold rolled steel
readily available is probably too large for your requirements.
An option in your area ( whatever that is) may be a machine shop
willing to manufacture a small lot of tubing for you provided their
equipment can be set up for " jeweler’s size" tubing. It would be
seamless but you may wind up paying more for their potential set up
cost, than just changing your specs a bit to buy mill products from
your regular vendors…
If you decide you want to try the short cut method using a 2 dollar
metal screw gauge contact me off list and I will give you all the
instructions ( really quite easy to achieve in a couple or three
hours time using fine silver or 18-22 karat gold - but they are soft
and the insert wire for the hinge should be 14 kt or even 12, 10 kt.
if gold or sterling if using silver to give the hinge it’s longest
wearing capacity. Also if you are using tubing solely to make the
hinge, then using a hard solder will be equally necessary to attach
the hinge sections ( presuming you are going to attach the outer
tubing first then saw out sections to attach to the other side of
the piece) that matches the colour of the metal(s) so keep that in
mind when ordering anything other than silver from vendors you don’t
normally use as most often colours don’t match from vendor to
vendor…
let me know if i can help further… regards, rer