# Making silver tubes for accent bands



## BRobbins629 (Jan 14, 2012)

In this thread 

http://www.penturners.org/forum/f56/making-accent-bands-pens-91842/

George discusses one technique for making accent bands. Those who have or want to try this will find one of the most challenging steps is finding a supply of silver tube in the diameter you want.  Here's what I do.

Start out with a wax cylinder.  These should be jewelers wax and are available from jewelry supply houses, ebay, etc.  I usually get mine from RioGrande.  I think the smallest diameter they make is 7/8” so the first thing I do is turn it between centers to about 3/4” so it will fit in one of my collets. (Note: wax can be easily turned with any tools you use to make pens- nothing special needed)   If you drill on a drill press, this is not necessary, but I like to drill on the lathe.  They are 6” long and I usually cut them into pieces about 2” long, but any length will do.







I try to make them somewhere between .015 and .020 thick so for what ever size you want, drill a hole in the wax about .030 to .040 smaller in diameter than what you want for an outside diameter.  Thinner than that are difficult for me to make and thicker is usually a waste of metal.

I turn the outside with the drilled tube mounted on a pen mandrel with home made bushings.  When the wax becomes thin, you will notice that it needs internal support, so I turn a piece of scrap on a 7mm tube that will be a snug fit in the wax tube and leave a little room on the ends for the bushings.

Now comes the easy part.  Take the tubes and ship them to your favorite silver caster.  I use Cranston Casting in Rhode   Island and have been using them for 3-4 years.  They are nice people, a small USA business, and have reasonable prices.  I usually get pieces back with 2 weeks after I mail them.  I think they have a minimum of about $50, but call and ask.  Typically I send about 10-15 pieces of various parts at a time. They also do gold.  They charge for labor and for whatever metal they use, typically in the range of $5 labor for a simple centerband, 6-12 for a clip and $15 for a complex overlay.  Silver casting grain is about $35 ounce now (subject to change rapidly).  You can estimate the weight of silver you will need by multiplying the wax weight by 10.

If you have scratches in the wax, you will have them in the silver.  It is a very true reproduction method with a very small amount of shrinkage.  The casting you will get back will have some small places of heavy silver where the sprues were attached, but these are easily filed off.  The piece will also be covered with fire scale which too is easily filed or sanded off.







EXTRA:  there is no reason as long as you have some wax that you can’t make custom finials, threaded centerbands, clips, overlays, etc.  Enjoy!


----------



## Curly (Jan 14, 2012)

Thanks for the information Bruce. Very generous of you.

Forgot to ask if there is any shrinkage corrections to worry about?


----------



## BRobbins629 (Jan 14, 2012)

Curly said:


> Thanks for the information Bruce. Very generous of you.
> 
> Forgot to ask if there is any shrinkage corrections to worry about?


There is a small amount of shrinkage, perhaps 1%, but since most of these will be for custom pens it typically is irrelevant.


----------



## Texatdurango (Jan 14, 2012)

Just thinking outloud, rather than make a wax tube to send in each time you want a cast made, isn't there a way to make a master mold of sorts that can be filled with hot wax then the wax tube popped out to be sent to Cranstons?


----------



## BRobbins629 (Jan 14, 2012)

Texatdurango said:


> Just thinking outloud, rather than make a wax tube to send in each time you want a cast made, isn't there a way to make a master mold of sorts that can be filled with hot wax then the wax tube popped out to be sent to Cranstons?


Master molds specifically for injecting wax are made all the time but not sure if the geometry of a long tube would work.  The video on Cranston's home page briefly shows the process.  Usually the master is the first metal cast from wax, but could be other things.  Since they are the experts, may be a good idea to call them and ask what the capabilities are.  They may have some ideas for both the originals and duplicates.  I'm sure molds could be made for shorter pieces as they would simulate a ring.  My volume is so low that I doubt that a mold could be justified, but perhaps there is a market for one of the vendors.


----------



## Chris Burton (Jan 15, 2012)

Bruce, thanks very much for posting that. It is the answer to something that I've been trying to solve lately. 

much appreciated,
Chris


----------

