Monday, April 29, 2013

Docs and the newest growing CAD materials

As new materials come into play for CAD models, be sure to review the CAD instructions for Docs. Long hot burnouts will be the order of the day. Docs can take the 1600 degree heat for this and maintain it's strength. This way you are far less likely to have any plaster break off and become inclusion porosity. 

Wednesday, November 17, 2010

A Small Selection Of Metals

A few of our alloys pictured so you have a chance to see what the alloys look like next to the 24kt gold. Unfortunately monitors do vary, but this will give you a very good idea of what the colors are like. This is just a small sample of the varieties avaialble.
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Sunday, June 20, 2010

Casting 14kw NRH

Casting our best 14k white gold, a nickel based alloy. Hydrogen/Oxygen torch and an open vacuum casting machine. A very inexpensive easy to use setup.
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Monday, April 12, 2010

GIA Tour

Some of the group.

Saturday, April 10, 2010

A close up of hydrogen as a fuel for smelting gold

A few images shot at our shop on GIA open house day. Once a year we have GIA students in through their alumni programs. The top picture shows the actual smelting of pure gold. Next is a shot of the gold being mixed with the alloy to make it into 18kt white gold. The next shot is that gold being vacuum cast.  At bottom the raw 18kt white gold castings.

The advantage of hydrogen for silver, gold and platinum is incredibly clean heat. 5000+ degrees Fahrenheit. Since hydrogen is an element as is oxygen, there is no carbon in the combustion as with natural gas, propane and acetylene. This illustrates how clean our environment could be if our primary fuel were hydrogen. The byproduct is pure water. One great precious metal that responds badly to hydrogen is palladium and palladium white gold.

Tuesday, March 23, 2010

Resin Cad Cam or Photopolymers

For those most difficult resin Cad-Cam models...

If you are using this material to simply overcome the defects that you encounter from the use of carving or RP waxes, you can just as well use a normal jewelry burnout cycle in the same oven as your normal daily production flasks.

Method B: (Smaller flasks or small flask-less castings)

Note: Casting flask-less is ideal with this type of material

· Program your oven controller for a ramp rate from 4 degrees per minute to a maximum of 10 degrees per minute. This investment material is very resistant to shock so your ramp up speed can be faster than with gypsum-bonded investment.

· About 1 hour after investing, put the flask into an oven that is preheated to about 300oF (150oC), with the wax button facing down.

· Ramp directly up to your top burnout temperature of about 1350oF - 1600oF, depending on the metal you are burning out. For photopolymer (Invision or resin based) use the 1600 degree peak temperature

· Hold your top temperature for 2 – 8 hours depending on the amount of material in the flask and the ending top temperature of your flasks. Lower top temps and higher wax content require a longer top temperature dwell times and higher top temperatures and lower wax content require shorter top temperature dwell times.

· It is always a good idea to flip the flasks over around 1200oF in order to allow combustion gases to escape the mold but is not necessary for longer burnouts.

· Your final flask casting temperature will vary and depends on the type of metal that you choose and the design of your parts.

· Quenching this material will not cause the investment to break away from your castings. This step is done at the appropriate time to give the maximum benefit to your metal crystal structure. You will then need to break away the investment using a hammer or a high-pressure water blast cabinet.

Monday, September 21, 2009

Our Finest White Gold

Announcing NRh or “No Rhodium” White Gold

The search for improved white gold never stops at PMWest. We are pleased to release our latest White Golds in 14kt & 18kt or White Master Alloy.

PMWest has been working on this white gold for over a year. Taking full advantage of the very latest metallurgical research and development-Precious Metals West announces availability of this breakthrough nickel white gold material for the custom fine jeweler or karat gold manufacturer.

This white gold will not ever require rhodium plating. This is an important cost savings both now and later. This is a gold you can cast yourself, rather than sending it out like you might be doing for Palladium white gold or platinum family metals including palladium.

A few technical points about PMWest’s NRh, or “No Rhodium White Gold”.

These white golds will torch or induction cast via vacuum or spin casting. The resulting button can be re cast or used for fabrication. This is a white gold that is perfectly reasonable to set, engrave or bend and manipulate for forming.

The preferred casting temperature for 14kt using NRh is 1140 Centigrade or 2084 Fahrenheit. Relatively high flask temperatures of 1100F or higher are suggested for all but heavy items. Rhodium is not needed! All the great color with none of the drawbacks.

Watch for more information to be released soon! Contact us vie email or our toll free line for pricing and other details.