A New Technique in Metal Inlay
I have been experimenting with a slightly different [metal inlay] technique that you might find interesting. It works like this:
Start with a true cylinder with the desired pattern carved in it. I use a CNC router setup for carving. In this case I have chosen a serpentine pattern. The pattern is cut 0.3” deep, but it need not be that deep. The depth required depends on your final design.
The part is mounted in the lathe, and the pattern is wrapped with several layers of heavy aluminum tape in preparation for the metal inlay.
Next, a one-inch hole is drilled in the end. This hole must be deep enough to go past the serpentine pattern. The hole is then hollowed out to reveal the serpentine pattern. Note that at this time you have two pieces of wood, held in position by the aluminum tape.
Now I mix the brass metal inlay material. I use SystemThree Mirror Coat resin:
6 cc resin
3 cc hardener
25 grams of powder
I used brass metal powder 325 mesh in hopes of getting a higher density inlay. The mixture is then poured in and the part is spun at 3,200 RPM (This is max speed for my OneWay lathe) for 15 minutes. Then the speed is reduced to a few hundred RPM until the resin is set. The initial high speed spin drives the heavier parts (brass powder) to the outside, and floats the lighter parts (air-bubbles and wood dust) in toward the center. In fact, when you first turn the inside, you will find resin with a lower or nonexistent concentration of brass powder. This seems to indicate that the proportion of resin and powder is not that important except that the mixture has to be thin enough to flow, and there must be enough brass powder to ultimately fill the pattern.
I have not experimented with different mix ratios, and have not tried other resins. It seems like most any clear resin would work with this application. SystemThree Mirror Coat has a long cure time, which ties up your lathe for a long time. Not too bad for us old retired guys, but not too good for commercial applications.
I also included a picture of a cup I just finished with a double chevron pattern. I had to do this one slightly different because I don’t think tape would hold the floating triangles. So for this one, I carved the chevron pattern 0.25″ deep, and then cut a number of short slots 0.35″ deep. Then I hollowed it out to meet the slots but not the chevron pattern. That way, the diamonds were still attached, and the pattern filled from the slots.
Note from Chris:
I admire your metal inlay work, and thank you for sharing your talent and techniques with the rest of us. I marvel at the graceful lines and arcs that you achieve in your work. I have watched your DVD several times, and learn something each time. I have been practicing the graceful arcs that you do – I still have a ways to go, but I think I am getting better.
Chris Van Peski
Chris Van Peski is an MIT graduate (1956 – before the transistor was invented) and spent most of his working years in the semiconductor industry, primarily in the wafer exposure area (credited with several patents to his name). In 2008 his employer, Sematech, moved to Albany NY, so it seemed like a good time for him to retire.
Chris says. “Woodworking is my main hobby, but I also enjoy baking bread and bagels. I bake four or five loaves of bread and a couple dozen bagels in a typical week. Mostly for neighbors, friends and family. And also, you just can’t beat a thick slice of bread hot out of the oven!”
Check out his website: (https://www.sites.google.com/site/chrisvanpeski)
Chris says he started the website many years ago, but admits, “I have not kept it up to date.” If you check out his website you’ll know why. There isn’t any woodworking project he hasn’t been able to figure out, and the list seems endless. It seems he’s always woodworking. I was impressed!
Note from Ted:
Thanks for sending me the beautiful goblet you made with the serpentine pattern. I also appreciate the detailed article you wrote on your personal technique of metal inlay and for granting me permission to reprint it in my blog. I love the fact that centrifugal force compacts the metal into a dense form that then appears solid. The beauty of this metal inlay technique is that the design is seen from both the inside and outside of the goblet. I suppose you can use the same technique even without a CNC router by drilling or piercing the wood. I can’t wait to see your next wonderful creation.
P.S. I might have to stop in for some fresh bread someday!