Wednesday, December 20, 2017

A pewter lapel pin

I've been mulling over this as part of a Halloween costume since I finished reading Doctor Zhivago a few months ago.  Early on in the 1965 film version, Pasha Antipov (Tom Courtenay) wears an unusual pin on his hat, a crossed hammer and monkey wrench, during his not-Bolshevik labor movement activities.  I've so far failed to figure out what organization this emblem belonged to, if indeed it was a real emblem (it's been so long since I've seen the film that I can't remember if it's explained onscreen), but a closeup publicity photo (inset) gave me a degree of detail which I attempted to copy.

I made the copy in wax, piecing it together and trying to keep its profile in proportion to the film version, but deeper from front to back for strength, with no undercuts.  Then I dabbed thin plaster into its front face and placed it face-down in the cutoff lower quarter of a plastic cup full of plaster to make an open-topped mold.  Once the wax was hard but still felt a bit damp, I peeled the wax out.  Two days later, I put the mold in a low toaster oven for an hour and a half to try to drive out any remaining moisture, and three days after that I figured it was time for casting.

I intended to use lead-free pewter, of which I had a small amount left over from making an akinakes chape for Marathon 2011.  But I couldn't find it in my house, even though I swear I saw it not long ago.  With no other option, I picked up some low-temperature solder at a hardware store - this is a lead-free, silver-bearing alloy, but it still had a low melting point of 430 degrees Fahrenheit.  It wouldn't surprise me if the one used in filming was a cheap white metal as well, though it could have been brass - it looks silvery to me in color screenshots, but as I well know, photography doesn't always accurately reflect actual colors.

Next I made a small pot for the actual melting and pouring of metal.  This is a 1-1/2 inch copper end cap, annealed and with a spout beaten in by means of placing the cap partly over a cross-peen hammer and smashing it into a block of wood.  Then I drilled a hole in the back and in the end of a piece of thick brass strip, and attached them with a copper rivet peened on the outside, over an anvil horn at Bucks' metal room.  Since the brass handle still conducts heat, it has to be handled with thick insulating gloves or a pair of pliers.  The pot may be heated on a stovetop or over a gas flame, which is what I did here, balancing it between two firebricks.

On my first attempt, I put way too much solder in the mold, giving it a large blobby back.  Attempting to scrape off the excess damaged the rapidly-cooling casting.  The mold broke on the first casting - perhaps it was still too damp; my foundry professor tells me that investment for jewelry is usually baked for around a whole day.  Or perhaps it couldn't withstand the heat even when dry, or my first attempt at divestment was what cracked it.  In any case, it was clear that I needed to try again, so I shoved the broken casting back in, held the mold together by wedging it between a pair of firebricks, and remelted with the gas torch.

Possibly as a result of the damaged mold, there's a lot of flashing below the hammer's head, which, as you can see, detracts from the striking appearance of the crossed tools.  I could probably file it out, but it would take a long time, and I think that the hammer's skinny neck, supporting the relatively massive head, would be prone to breaking without the flashing to strengthen it.  Also, obviously the threaded middle of the wrench isn't as finely threaded or clear in detail as in the film version - the former being the fault of my original wax (it's not easy to cram such fine detail into a wax model) and the latter either because of me failing to work the plaster between the grooves as thoroughly as necessary or because the solder failed to flow into every crevice.

The proportions are slightly off, but I think adequate for a homemade costume - of course if this were professional work, then I would want it to be truer to the film version.  The apparent bend of the hammer's neck over the wrench isn't nearly as noticeable in person; I think it may be largely a result of the lighting here.  White metal is difficult to photograph under bright sunlight, as it glares a lot, obscuring details, so I waited until I had time to take photos when it was cloudy out.  The pin was actually finished last Friday.

With the poured solder sitting in the mold, I blasted the torch over it to make sure it was still liquid, then put a common jewelry pin in the back and tried to drag some solder on top of it with the tip of a piece of thin steel rod.  As a result, the back is pretty rough in texture.  It's probably not a very secure attachment, but as the uses this pin is going to be put through are not high-stress, it should be good enough.

I tried to clean up some of the flashing and smooth the surfaces with a fine file, then buffed the entire front with a carbon steel Dremel brush.

Tuesday, August 15, 2017

Dracula and Frankenstein's Monster

I had only set out to draw Adam, but I already had a design in mind for Dracula...  so why not.

Adam is an interesting challenge to visualize.  Frankenstein "selected his features as beautiful," so I tried to draw his face with normal human proportions (perhaps his jaw is a bit less deep than it ought to be).  The result doesn't give nearly as big and boxy an aspect as I'm used to seeing him drawn with.  Also, I understand him as basically looking like an anatomy chart with skin shrivelled so tight that it doesn't properly conceal the tissues underneath.  In my first attempt, I thought I delineated the neck muscles too clearly, as if he had no skin at all there; this version, by contrast, almost looks normal.  Perhaps it's not possible to do justice to the fine detail that really makes Adam as disturbing as he's supposed to be, with just a pencil at this scale.  I ought to do a closer-up drawing of just his face at some point.

Dracula is much easier to draw.  He's given a very detailed and clear description, and, although he has inhuman features like pointed ears, his overall impression is that of a normal human, which is ironic because he's not one at all, whereas Adam is.  So there isn't the issue of trying to capture anything subtle or truly unusual.

Tuesday, May 9, 2017

Peace, man

I dished this 14ga. brass circle several years ago and never decided what to do with it.  Last week, the idea hit me.

The front is etched with ferric chloride (a full hour this time) and patinated with some other kind of ferric compound, probably nitrate.

The back has a one-piece, fibula-style pin, secured with plenty of silver solder.  The back and front are finished with a polyurethane varnish to try and preserve the burnished finish for a while.

Since my casual jacket right now is an old surplus jacket (a Swedish M59, to be specific) I figured some peacenik regalia would balance it out a bit.

Monday, April 10, 2017

Small belt knife

This is my new personal knife - and, insofar as I "need" one (only for small tasks like opening and cutting up boxes), likely the only one I'll ever need outside the kitchen or art projects.

It's made to an 18th-century Scottish aesthetic to go with some of my other projects, scaled down to the size of what we would now call a patch knife*.  The blade geometry isn't correct for the 18th century, since it's a modern Lauri blade from Finland, but this was the best I could find in a bare blade without going custom.  (Judging from every photo I've ever seen, real 18th-century knives had a triangular "backed" cross section.)  Specifically, it's the 80mm Lauri stainless blade distributed in the U.S. by Ragnar Forge.  This is a heavy blade for its size at roughly 1/8 inch thick, designed for whittling and general work.

I modified the blade, grinding the tang upward on the edge side and the spine down a bit on the back, so the tang is off-center and the blade has a little shoulder.  Also, it transitions to slightly rounded at the very base so as not to leave any corners sticking out where it meets the ferrule.  Lastly, of course, the traditional jimping which is supposed to add grip when pinching the spine to work on delicate tasks.

The blade came with mirror polish but also a faint ribbed surface which I assume resulted from the initial factory grind.  I sanded and polished it to a near-satin finish that didn't quite manage to get rid of the ribbing, but obscured it somewhat.

The ferrule is a copper plumbing end cap.  These are made circular with slightly rounded ends, but annealing and a few minutes with a hammer give it a roughly oval cross section and flat top.  More challenging was the brass plating.  The old lye-zinc trick, used to give pennies a zinc plating which is then heated to fuse with the copper coin and produce a yellow brass coating, only produced any significant deposition on the spots where the ferrule was in direct contact with the zinc dust.  Worked great on a penny I, though.  I theorize this process doesn't really work except on thin, flat objects.  (Also I had a bit of a cough after the attempt; maybe the lye fumes hurt my throat?)

What worked better was electroplating, using two AAA batteries in a battery holder and a much more benign mixture of zinc, vinegar, sugar and epsom salt in a one-quart plastic yogurt carton.  The ferrule plated in seconds, polished up to a nice silver and produced a solid brass finish when heated.

The grip is American walnut with linseed oil.  I threaded the tang and ground down a brass hex nut to secure it, and assembled with epoxy for good measure.  Lastly, the sheath is good old vegetable-tanned leather, though a bit lumpy because I'm not very good at skiving, dyed brown and polished with shoe wax.  It fitted loose, but I shrank it with soaking and judicious warming over a heater (which I understand can ruin a sheath if done to excess - thankfully in this case it worked out.)

* A number of Scottish knives are preserved that resemble a mashup between a Highland dirk and a chef's knife, typically having a triangular blade and hafted with antler or carved wood, as on one thought to have been recovered from the field of Culloden.  These are sometimes identified today with the knife referred to in literature as a sgian achlais.

Sunday, June 12, 2016

Flute carrying bag


For her birthday this year, Mom pointed to a flute bag in the Crazy Crow catalogue and asked for one to fit hers (a concert flute somewhat too long to fit into the one they offer) for carrying to Market Day and other local vaguely Colonial events.

I made this one from a split, chrome-tanned garment buckskin with a dark red, hard-faced cotton twill lining to keep the weight from stretching and bulging the leather, and prevent too many shed leather fibers from getting into the instrument's workings.  The fringe is some large straps of leftover German-tanned buckskin.  The bag is folded and sewn inside-out with the fringe facing inward and the lining on the outside; when it's turned rightside-out, the fringe now sticks out and can be cut into strips.

The drawstring and shoulder strap are more German buckskin, but the small bits connecting the strap to the bag are a much denser, tougher chrome-tanned cowhide.  I handmade two pairs of soldered brass D-rings to attach the shoulder strap to the bag at the correct angle.  The cowhide bands are secured with tin rivets and steel washers; I would've preferred copper, but the hardware store didn't have any that were short enough.

One improvement I'd still like to make would be to line the shoulder strap with a smooth leather so it won't shed fibers into one's clothing.

Sunday, May 15, 2016

Presentation box for my letter opener

Yesterday I finished up my fine woodworking fundamentals course.  There were exactly two projects in this class (aside from doing a practice set of dovetail joints), a picture frame and a box.  I'm not publishing the picture frame because it's very plain and uninteresting.

I made the box to fit the letter opener I finished in September.  The finger joints reminded me of masonry, so it's obviously inspired by West Asian architecture, particularly the palaces of Persepolis.

It consists of American or black walnut and soft maple.  Unfortunately, the walnut's color varied a lot through the plank.  For finishes I had a choice of boiled linseed oil, tung oil-based varnish or water-based polyurethane, but being short on time, I was forced to go with the polyurethane, so its finish is still a bit rough (the professor noted that polyurethane, in her words, "bubbles" a lot when brushed on; it requires repeated sanding to look good).

It has two brass-plated steel hinges.  Sadly, copper to match the letter opener's furniture seems to be unavailable.  I might try to fabricate my own in the future.  The letter opener and scabbard are supported by two inserts carved from rigid pink insulating foam and covered with epoxied polyester suede cloth.  A considerable amount of epoxy seeped through the cloth; clearly I should've found something with a non-porous back.

Because the box is so small and cut to fairly tight tolerances, it's feasible to have the upper insert rest on a pair of narrow shelves over the lower one so the box can be more compact.

This was a good class for learning the use of the major standing equipment and how to get the greatest precision in fit.  Most of the work is (if you do it correctly) done on the planer, table saw and routing table, machines with which I was totally unfamiliar before.  It also gave me a chance to get started on a handful of personal projects which I can finish up over the summer.