Cactus Juice and Bangles

Barry Gross stopped by our April Meeting and gave us a great demonstration on how to stabilize wood and then use those pieces to make an elegant bangle.

So what is Cactus Juice? It is a heat stabilized resin that converts porous and punky woods into usable pieces for turning. It's low viscosity allows it to replace the air and moisture in wood when placed in a low pressure chamber.  Barry's company, Arizona Silhouette, sells two sizes of chambers, a 10 inch and 14 inch long, both with 4 inch diameters.

Barry starts by filling his chamber with some spalted wood rings, then tops those with a retainer to hold them under the liquid. Note that the chamber is fastened to wood base to prevent it from tipping over. Next comes the Cactus Juice; he fills the chamber enough to cover the wood and about an inch more. He leaves plenty of space above the parts since the liquid foams when the vacuum pump is turned on.  Barry's careful to regulate the pressure in the chamber with a simple valve to prevent sucking the juice into the pump.  That would not be good!  Barry uses a Robinair VacuMaster pump that he got on eBay for about $120. He figures you can find a pump on-line for between $65 and $135. The Cactus Juice is stable for about a year after the two part system is mixed so you can just leave it in the chamber until you are ready to infiltrate your next batch. Barry does caution that your wood should be relatively dry. Green wood will put too much water into the Cactus Juice and inhibit its curing.

Once the foaming stops you are ready to cure the pieces. All it takes is a toaster oven, a piece of foil to protect the oven and, ideally, an oven thermometer. Barry and Matt Overton found inexpensive ovens at Walmart for about $19, so don't use the one in your kitchen! Set the temperature of the oven for about 200 degrees F and let those parts cook for about two hours. Let's look at  how do you make those rings in the first place.

Barry suggests you start with a 3 3/4 inch square of wood that is about an inch thick, and then use a 3 1/2 inch hole saw to determine the outside diameter. Remount the disc in the Jumbo Jaws and with a 2 1/4 inch hole saw create the ring. Barry's website conveniently provides you with all the information you need: just click on  the bangle you want and you'll find a pdf of instructions and everything else you need. The two hole saws mentioned above work for all bangle sizes. You should check out the Instructions, they are very complete!

Once you have the blank stabilized, use a four jaw chuck with some shims to stand-off the blank from the face of the chuck so that you can turn the inside of the blank to fit the inside of the bangle insert.

Barry likes to use a 1/4 inch parting tool to lightly remove wood from both sides of the inside to create a loose fit with the insert. After getting the inside diameter right, he then mills the thickness of the bangle to fit the width of the insert. 

The split bangle cores make it easy to create a very strong bangle regardless of the wood.  Barry uses Liquid Nails- Home Projects to glue the wood to the metal; it remains compliant even after it cures. Spring clamps keep the assembly together during the cure. Once it is cured, the bangle is easily mounted in the four jaw chuck and then it is up to you to determine the profile. Barry uses a scraper or bowl gouge to do this shaping. The final step is finishing. After sanding, you might try Odies Oil or some of the other finishing products Arizona Silhouette has to offer.