Metal Musings Blog

Well, the owl worked out so well, I decided a hummingbird was in order.  If you recall the “encouraging failure” from the first post in this series, I used the copper sheet pressing from that to chase a small hummingbird skull.  That became the model for a press die.

The original “encouraging failure,” above.

Above, I’ve begun cutting out the hummingbird press die from a 5/8 x 5/8 inch square piece of O-1 carbon steel I normally use for making my knives.  Why O-1 and not mild steel?  I had it on hand and it was the right size.  No other reason…


The above two images are of the finished press die and the original “encouraging failure” hummingbird skull.  Note that I’ve drilled and tapped a 10-32 hole through the skull of the press die, before I cut out the profiles of the hummingbird skull.  That will hold the skull securely to the “pusher” I’ll turn from aluminum.

Above is the first copper sheet pressing on the die.  Since this is a considerably smaller die than the owl skull, it only took three pressings to get this far rather than the four it took for the owl.

Above, the completed die and the completed first pressing.

There’s been a little madness to my method here.  Above, I’ve made another pressing and am going to shorten the beak to make a tiny raven skull.  If you think about it, this partially-formed hummingbird skull shape is pretty generic for a lot of different birds, if you ignore the long beak.  You can also see the specialty pitch block I made up for this press die as well.

By the way, I made the press die extra tall just for this reason.  There are a lot of different bird skull this basic form will be appropriate for, saving me a bit of labor making different press dies.

The above two images show the press die, a normal pressing and the finished raven skull.

Above, I’ve completed a copper humming bird skull and a silver version as well.  Now to make a pendant from the silver one.  I don’t know what the copper one will become yet.

I guess I should also tell you that after cutting the hummingbird skull free from the metal sheet, I take it to the anvil and carefully forge the open bottom of the beak closed on the anvil, with a tiny hammer.  Picture a tapered tube, with overlapping bottom edge.  Note that I don’t do that for the raven-style beak.

Thanks for looking!

Now it’s time to begin the finishing process.  I’m going to be “chasing” the final details here, so will be filling and embedding the copper piece in pitch.  But, since I intend to use my Lindsay Airgraver in the chasing process, I’ll need a fixture I can place in my engraver’s vise under the microscope.  To facilitate that, I’ve turned a hardwood cylinder (about three inches in diameter) and excavated a pocket for the pitch.  You can see some small pieces of pitch in the background.  I get my pitch from Northwest Pitchworks.

Above, I’ve begun filling the pocket with pitch.  I’ve already melted a layer of pitch in the bottom, and am adding more for the next layer.  I’m using a heat gun to melt the pitch, but a soft “bushy” flame from a plumber’s torch would work just fine as well.


Above is my copper piece mounted in the hardwood cylinder, and clamped in my engraver’s vise.  The cylinder is important here because it allows the piece to be rotated in the engraver’s vise and held very securely.  You can purchase similar inexpensive wood fixtures here.

Here is the hardwood cylinder and copper piece mounted in my engraver’s vise.

Here I’ve penciled in the details I’ll be chasing in.

Above, I’ve begun chasing around the bone eye ring.  I’m using a 90 degree “liner” I made, in my Lindsay NitroG20 Airgraver.

Above, you can see the 90 degree “liner” and a magnified view in the inset image.  I made this from hardened 1/8 inch diameter piano wire.  At this scale, I need the business end to be smooth, but not necessarily polished.

Above, I’ve finished chasing in the bone eye ring edges, and textured the inner area with a simple hardened piano wire punch.  Notice I’ve also been further refining the shape of the tip of the beak as well.

Above, I’ve used my NSK micromotor and carbide burs to carve out the center eye circle.  You can see the little copper plug I removed lying nearby.  I found it was much easier (for me, at least) to carve the skull free from the waste copper than to try and hold it at the many odd angles it would take to cut it free with a jeweler’s saw.  But, that might just be a personal problem…

Above is the other side, and I’ve also begun carving away the base of the skull.  You can see the two sizes of carbide burs I’ve used.  I found the smaller one worked much better in close quarters like the tip of the beak.

Above several images, other views of the same.

Above, I’ve used a small torch to heat the copper and get it to release from the pitch.  I don’t want to heat the pitch too deeply here, since I’m going to want to use this same fixture and pitch for the other owl skulls…

Here’s the finished skull after cleaning it up with abrasives and files, along with an unfinished version.

Above, the finished skull after patinating, but before polishing the surface back a little with 0000 steel wool.

Above, a beauty shot of the entire process, start to finish!

And, finally, the finished version.

Here’s the finished pendant.

Thanks for looking!

Above images courtesy of BladeGallery.com

And a work-in-progress image of my own.

In the past I’ve experimented with carving bird skulls from antler, and some with small helmets.  While they proved popular, all of the above works were terribly labor intensive.  While stumbling around the Internet, I found some videos from Rio Grande jewelry supply showing the Bonny Doon Press in operation.  This started ideas rolling around in my noggin, and a little more research led me to PotterUSA.com and their inexpensive jewelry presses and contained urethane.  Since I already have a small 20 ton hydraulic press I use for bladesmithing, that added fuel to the fire, and here we are.  Here’s a little hint – since many bladesmiths have a hydraulic press for forging, they might take note that this process could easily be adapted to create silhouette dies that could be used to make metal halves of sheaths.  Here’s a pretty decent video about silhouette dies by Melissa Muir – bladesmiths take note of the possibilities…

Above is my (semi) finished first success.  It was a bit of a winding road, but I seem to have broken at least some of the code.  I can now make multiples of this design, with maybe 70% less work for each.  Here’s how I got there…

Above is my first attempt, something I think of as an encouraging failure.  I carved a positive bird skull shape in walnut (grain oriented vertically) and glued it onto a 2 inch diameter, 1 inch thick circle of walnut (grain oriented horizontally).  The press squashed it like a soft rubber hockey puck.  But, the small sheet of copper I used was partially shaped well enough to encourage me to make a metal die.

I decided on an owl skull, since my contained urethane is only 2 inches in diameter, and owl skulls are round rather than long.  I figured I could make a pressing large enough to make a pendant sized piece.

Here is my pattern and research material.

Above is the beginning of the owl skull form, sawed from a 1 x 1 inch square mild steel bar.  You can also see my PotterUSA contained urethane in this image.  This little plug of urethane is quite hard, I’m unable to dent it with my finger, but it will serve as the resistance medium to form thin copper sheet around the owl skull form.

Here’s one side partly ground with an angle grinder.  I’m leaving the skull attached to the bar to help hold this slippery little thing…

I’ve drilled an tapped a hole in the bottom to hold the skull onto a metal plate during pressing.

Partly ground – note the center line I’ve drawn on with Sharpie permanent marker to try and keep both sides identical.  I often use red Sharpie because it doesn’t show blood as easily…

More grinding and a few features drawn in.

This is as far as I can go with the angle grinder.

Above, another center line and additional features.

Here I’ve begun adding inthe eyes with my NSK micromotor and carbide burrs.  Note that I’m not carving anything below the halfway mark – if I carve there, the urethane will force copper into the concave spaces, trapping my form after pressing.  That would probably cause damage to either the copper sheet or the form itself trying to remove the pressing.

The other side – same story, different day…

Things smoothed out some…

Above, I’m using a small drum sander to finesse the shape and smooth the surface.

Now I’ve cut the skull from the steel bar, ready to file and grind the back side.

The above two images – using coarse ScotchBrite™ and jewelers files to refine and smooth everything.  I want the form to be smooth, but I don’t think it needs to be polished.

The above two images, the finished form left and right sides.