Poured Pewter inlays tutorial
Of all the historical techniques I use, inlaying wood is up there at the top of my list. There are so many different styles of inlays from the finest wire tendrils and finely carved and inlet sheets of fine silver, brass, pearl, you name it - beautifully set flush with trace a gap in the surrounding wood. Then there are the sometimes crude folk art styles hand carved by flickering candle light or the glow of the campfire that exhibits all manner of skill and material at hand. By far the most interesting, at least process wise, is what is known as poured pewter inlays. As the name suggests this process relies on the quirky fact that pewter metal (an alloy of mostly tin with small amounts of antimony, copper, and/or bismuth to control hardness and flow characteristics) melts at a lower temperature than wood burns! This allows the craftsman to literally pour the inlays inplace and was used historically in many places and time periods around the world. The technique became especially popular in early America where pewter was readily available in cheap tableware: silver was currency under the Crown and prescious little made it's way into the interior. Pewter on the other hand was traded far and wide with the Native Americans and could be worked in the nightly fire at home or on the trail. Inlaying it as a liquid offers it's own challenges but where our handy forefathers might grab a piece of green tanned buckskin and stout string, today we use paper and tape, the process is the same. A recent project came up with a request for the technique so I decided to document the process and share the the tricks I have gleaned from too many maker's to name. "Traditional" technique as it comes to me via tutorials etc online and in print.
To start you need to carve exactly what you want the inlay to look like on the surface of the wood. This can be really as simple or complex as you like, but generally straight lines are easier than curves and direction of grain in ease of carving is a smart thing to pay attention to. In my own work I try to work as masters of old did by eye and rarely measure, so lots of time looking at historical examples from the target period 1760-1830 to match the head and getting a feeling for historical designs, line weight, etc, etc.
Working from a sanded or scraped surface (400grit+) trace in the design with graphite pencil, some designs I would be tempted to use graphite transfer paper for the same result. Try to make lines clear, avoiding corrections, better to erase and start again than to push harder on the pencil. As soon as you are 100% happy with your drawn layout hit the area with artist fixative to lock that graphite down! Many an hours of sanding can be saved if you do not smudge the graphite into the wood fibers. Trust me I know.
The inletting should be square with the surface and the bottom generally square to the sides (tight spots are open to interpretation and tools available). I normally cut all the cross grain sections first, laying out the pencilled lines with first the saw, then the knife, and then a fine mill dastard file with a safe edge to clean everything up and get all the inletting as smooth as possible. Sharp corners in the design can be slightly under cut to encourage the metal to flow but otherwise it is important to keep everything 90 degrees and square to allow the best flow pattern for the metal.
Another neat trick to get crisp straight bands across wood grain in to use a micro fine jewelers saw to trace the inside of your pencilled lines. The fine blade sets the perfect stop cut that can be later be filed to a gleaming surface.
After everything is inlet, square, and filed smooth (all mistakes will be highly visible so decide how to deal with them before progressing) we're ready to prepare for the pour! Maybe not totally necessary a great trick I learned from the gunsmithing community is to rub everything down with pencil. First it burnishes the surfaces of the channels and also the graphite acts as bearing surface allowing the molten metal to flow faster into the entire design before it cools. As with all casting flow rate, speed of cooling, complexity of the channels and escaping of air from the cavity needs to be accounted for for the casting to work. There are a whole host of failures inherent with any casting technique and working with molten metal should be fairly understood. The graphite seams to elevate a few of the veritables so is worth the time. We only have one shot at the pour and a failed pour in a bummer to be avoided.
A new trick to me is to use masking tape as a bed, only one layer deep to slightly over pour the design. Over pouring helps fill blind bands and more complex designs. Not always needed but part of the arsenal. It also tends to help everything seal up as a leak in any of pour and it is game over.
I lay out a strip of paper, I use manila folders from office supply. Maybe an inch wider than the widest part of the design and long enough to go all the way around with an inch or so on each side. Holding the paper inplace I mark where both flaps overlap the opposite of the handle. I want a good 1/4 or more of overlap. I find punching holes in the paper discourages it to tearing later. Then V cut to the punched holes on both flaps to create a funnel for pouring
I create the funnel by first taping the overlapping ends of both flaps so the paper is as tight to the surface as I can get it, then I tape down both edges of the paper 3 or more times around to make sure nothing can leak or come undone when hot. I now push the corners of the mouth I've made towards the center to create a funnel for pouring. Using a poker is helpful for pushing the paper from the inside. Try not to rip the paper, but mistakes happen patch as best you can or start over remember you only have one shot at this working, getting everything just right now saves a lot of work later. I specially pay attention to the intersection where the funnel meets the cavity with criss crossing tapes over the shoulders and extra wraps up the funnel to hold everything together. Historically I've been told they used partially dried fresh raw hide and stout cordage. The moisture content was important as the steam jacket served as a form of gasket. I've never gotten it to work
Metal is melted and poured! It always blows me away that the hot molten metal can touch the untreated paper with only the slightest hint of smoke. This is a new alloy to me called Britannia metal as a type of lead free pewter and I am sold. It melts lower, stays molten longer, cools harder then anything I've worked with before. Any takes a beautiful patina rather than modern "tarnish free" alloys.
As soon as it's cool enough to touch you know it has solidified so pull off all the paper and tape and see what you got! This pour out of three was slightly over heated and I got some smoke bubbles that frothed up the end of this open cast mouth piece, but the blind band castings went more than perfectly. In my work I often live with my mistakes as inherent in a handmade process but depending on severity a 800w soldiering iron and some determination can fix a lot of the common defects. But sometimes nothing can be done and it's game over. Carefully try to remove the casting, or try to pour around it, do everything not to fail in the first place.
Now file the pewter down the the surface. I find pewter smears pretty easily not to mention grey dust if you try to sand it. Stick with sharp traditional tools like files and steel cabinet scrapers to bring up to finish to match the surface. Keep working on the surface until all the lines are straight and clear (here is ways it is important to cut the inlet at 90 degrees, some times you might need to go a little deeper to get past a defect in the casting and if you undercut you loose your design) smooth flush with the surface.
Be sure to have a break and let the shop cat inspect everything for quality control
Now if you are really creative this pewter surface is a blank canvas for further decorations; engraving, this case wiggle-work, scrimshaw, filing, etc. Patinas easily with a few bottled patinas, check stained glass places for "lead alloy" backings and other colors.
Thanks for looking through this tutorial hope it helps the next generation of makers! To see more how-to's and tutorials of Iron Tree Forge click here! Also remember to become a member of this blog and next miss another project again. For current on sale pieces check out our available tab. Thanks again!
Iron John Logan