Snag News Volume 18 Number 3 June 2010 33
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SNAG NEWS VOLUME 18 NUMBER 3 JUNE 2010 33 TECHNICAL ARTICLE ..................................................... Alternative Methods for Patterning Mokume Gane - Part 1 by Victoria Lansford This issue’s Technical Article is by Victoria Lansford, an accomplished maker, educator, and author. Please visit her website, www.victorialansford.com, for more about her numerous articles, books, DVDs, and studio pieces. Because of the amount of information she has to share about her use of mokume gane, we have split her article into two parts. The next issue will feature the second part of her article that addresses the combination of fold forming and mokume gane patterning. As the newest Technical Article Editor, I am proud to contribute to the longstanding commitment that SNAG has to the sharing of information for our field. From the earliest issues of the Golddust newsletter, there has been an important exchange of knowledge and experience that keeps SNAG and our field vibrant and dynamic. I encour- age everyone reading to contact me about potential topics and authors. Thank you! -James Thurman Enraptured, Eastern repoussé cuff bracelet from straight grain mokume gane, sterling, copper, shibuichi; 2-1/2 x 2-1/2” x 1-1/4”, 2010 Mokume gane, which translates to wood grained metal in Japanese, is a laminate of different alloys that can be manipulated to create patterned effects. The sheets of these various alloys that comprise a piece of mokume can be welded or soldered together to create a single billet or sheet of metal. Of the two methods, however, welding creates a far stronger bond that will withstand the manipulation required to create many patterns. While there are several classic patterns that can give consistent results, the possibility of more patterns and ways to de- velop them is endless. Most anything that displaces and distorts the layers of flat (unpatterned or straight grain) mokume gane can produce some sort of pattern. Purists may wish to create mokume billets from scratch.1 For those who don’t, Shining Wave Metals2 offers unpatterned mokume in a variety of contrasting alloys available through Reactive Metals Studio and Rio Grande®. For me the reward of patterning comes through various metalsmithing techniques that create texture and form with an “accidental” pattern as the result. The processes that have the greatest pattern potential are those that significantly displace and deform the sheet itself. Merely bending the straight grain mokume is not enough. SNAG NEWS VOLUME 18 NUMBER 3 JUNE 2010 34 TECHNICAL ARTICLE ..................................................... Alternative Methods for Patterning Mokume Gane - Part 1, continued by Victoria Lansford Cross section of straight grain mokume layers. Cross section of straight grain mokume layers in bent or curved sheet. The pattern is revealed by grinding off the surface marks after forging or forming is complete, so it’s important to consider how thin the metal may become by the time it has been forged, formed, and ground down. The result is like scratching off a lottery ticket to find out if you have a winning number. Cross section of mokume layers after forging. Red line indicates down to where the metal might be ground Since most pre-fused straight grain mokume comes 14 gauge or heavier, it needs to be milled in a rolling mill to thin it to the necessary gauge for the particular process. As the sheet gets lon- ger, the layers of metal become much thinner, which will result in smaller, delicate, and more subtle patterns. When rolling down, be sure to anneal frequently! Trying to roll the metal too quickly might cause the layers to split or separate at the edges. If turning the crank of the rolling mill feels too diffi- cult, then open the rollers farther apart. You can decrease the space in the rollers a quarter of a turn with each pass. Anneal the metal every pass or two. Always anneal when changing the direction of the sheet in the rollers. Heating to cherry red increases the risk of melting the layers together, which could result in one big blob of an alloy instead of multiple distinct layers. I use a permanent marker to indicate the temperature of the metal when annealing. Make a large mark in the center of the sheet and anneal as usual. When the mark has faded away, the metal is annealed. A blob of paste flux on the metal will also indicate that the metal is annealed when it has turned glassy. SNAG NEWS VOLUME 18 NUMBER 3 JUNE 2010 35 TECHNICAL ARTICLE ..................................................... Alternative Methods for Patterning Mokume Gane - Part 1, continued by Victoria Lansford Eastern Repoussé from Straight Grain Mokume Gane Cartouche II, Eastern repoussé pendant from straight grain mokume gane on a Roman chain, fine silver, sterling, copper; 1-3/4” x 1-1/16” x 3/8”, 2010 Eastern repoussé is a form of repoussé and chasing that involves delineating an area to be raised and working it from both sides to achieve high relief. It is usually worked within a matrix of sheet, which may be cut away later. In terms of malleability, using mokume for this technique differs little from using sterling except that it requires annealing more often. I use straight grain mokume, rolled to 23 or 24 gauge. There are several comprehensive publications on repoussé available (including my own3), so what follows is an overview of the process of Eastern repoussé, illustrating what creates the mokume pattern on the surface. After transferring and scribing my design onto the metal, I hammer the lines with a line tool over a bench block. SNAG NEWS VOLUME 18 NUMBER 3 JUNE 2010 36 TECHNICAL ARTICLE ..................................................... Alternative Methods for Patterning Mokume Gane - Part 1, continued by Victoria Lansford I embed the piece face down into plasticine and hammer from the back with oval shaped push tools. At this stage, I am only concerned with pushing out the overall rounded rectangular shape, so I ignore the interior lines of my design. I go over the exterior lines again from the front and then anneal. This stage usually takes between three and eight rounds, depending on the size and depth of the piece. After I have puffed out (a technical term) the overall shape, I put the piece face up on pitch and go over the interior lines with a large line tool. SNAG NEWS VOLUME 18 NUMBER 3 JUNE 2010 37 TECHNICAL ARTICLE ..................................................... Alternative Methods for Patterning Mokume Gane - Part 1, continued by Victoria Lansford Now that I can see the interior lines from the back, I place the piece face down in plasticine again and begin to puff out the individual shapes. The secret to added height in this technique is what I call, edging, hammering at an angle with a special tool just inside the lines. This stretches the metal in areas where it might not otherwise be stretched before I continue puffing out the rest of the shape with a large push tool. In between rounds of pushing out from the back on plasticine, I lightly go over the lines from the front on pitch. SNAG NEWS VOLUME 18 NUMBER 3 JUNE 2010 38 TECHNICAL ARTICLE ..................................................... Alternative Methods for Patterning Mokume Gane - Part 1, continued by Victoria Lansford To create the peaks and valleys characteristic of my style of Eastern repoussé, I compress the sides of the high relief areas by planishing them with a large planishing tool. In non-mokume pieces, I do two to three rounds of successively finer planishing so that the final hammer marks are refined and even. In mokume pieces, I do one to two rounds of planishing, leaving the final hammer marks slightly rougher. By grinding these marks off, I reveal the pattern that results from the process. Endnotes 1. Steve Midgett’s DVD, Mokume Gane in the Small Shop is a won- derful resource for learning how to make mokume from scratch, available through . 2. www.shiningwave.com 3. For more detailed instruction on this style of repoussé, see Metal Technique of Bronze Age Master: Eastern repoussé and Chasing, DVD, available through . Part Two of this article will appear in the next SNAG News..