Monday, February 28, 2011

Making the Steel Ulu

ready for rivets and antiquing
This is a follow-up post to the ulu reproduction mentioned in the previous blog post.  Despite the time crunch that I'm feeling, I'm really regretting not building a second ulu alongside this one for myself.  I'm sure that I'll attempt it, or a similar one again someday so I want to record some of the steps while its fresh in my mind.

Muriatic acid accelerates rust
For the blade, I used a stainless steel cleaver that I bought at the Magic Wok on Duckworth Street.  It has just the right dimensions and gave me a nice, clean steel blank to start with.  I cut the corners off with an angle grinder and used the grinder and hand files to finish shaping and sharpening the blade.  To mimic the pitted and rusted surface of the blade I covered the blade with a very fine sawdust and sprinkled a bit of muriatic acid solution into it.  It only took a few hours on each side to create the antiqued pattern.  I then soaked the blade several times in tea to help turn the reddish pink rust a darker blackish colour, to mimic the look of a conserved metal artifact.

Antler stem
The neck of the handle is caribou antler.  The general shape is a natural flare, where a tine starts to flare out into a flat palm.  When I had the rough shape cut out, I soaked the antler for about 24 hours in white vinegar to soften it.  I wanted the slot for the blade to fit inside the soft spongy part of the antler without cutting through the dense outer layer.  Softening the antler in vinegar first let me bend out the slight irregularity in the shape of the palm.

Cut musk-ox horn for the handle
The small grip across the top of the antler is musk-ox horn.  I used the smallest part of the horn that I could that matched the dimensions of the original artifact.  I think there are still 2 or 3 more similarly sized handles inside this small horn.  I cut the horn with a scroll saw and shaped it with an electric sander.  Its comparable to soft wood or antler and shapes very quickly and easily with sanding, although it was that distinctive, unpleasant burnt hair smell as you cut or grind it.  Its predominantly held in place with friction, although I also added some hide glue to fill up any gaps and to make it even more secure.  I left the antler neck a little longer than necessary and sanded to top down flush with the musk-ox handle when it was fit in position.

drill the antler and metal apart
I needed to drill holes through the antler and the ulu blade for rivets.  I marked the position of the holes on the antler and drilled through the antler first.  I put the undrilled blade back into the slot and marked the position of the holes on the blade, through the drilled antler holes with a pencil.  Then I drilled the pencil marks out using diamond abrader bits on the dremel tool, plus water to keep from burning through the blades.  I don't really have a steel working shop, so this was the step with the most room for improvement.  I'm sure a drill press would have done a much quicker and better job.  The main thing is to not to drill through the antler and the metal together.  Its too easy to shred the antler when the bit hits the harder steel inside and starts to dance around.

tea staining works on metal and the organics
After I drilled the holes, but before I but the rivets in, I antiqued everything in tea.  I wanted the tea to stain the antler and horn a reddish brown, and the blade black.  I didn't quite get as much red from the tea as I was hoping, so I touched it up on the surface with a bit of red ochre.

Annealing the copper rivet rod
The copper rivets were slightly more laborious than they needed to be because I started with a a heavy copper ground wire that was much thicker than I needed.  I hammered, ground and filed it down until it was thin enough to fit through the holes.  If I had it in the workshop I would have started with a narrower gauge of wire.  Since I was hammering I needed to periodically anneal the copper with the blow torch to soften it again and prevent it from becoming brittle and fracturing while I worked it.

Ready to cut to length
Starting to tap out the rivet head
When the copper was thin enough to fit through all the way through the antler and blade I would cut it off and move on to the next hole.  I worked on all the rivets at the same time.  The wires in the photos are a little longer than necessary.  Next time I'd make each on a millimetre or two shorter.  If the wire is too long, it will want to bend over rather than flare out as you hammer it.  I'd hammer the rivets on the anvil, being sure that the opposite end of the rivet was supported by the anvil.

Finished rivets flattened out
Even one light hammer tap on the antler can leave a dent that is impossible to remove.  I hammer very slowly.  Alternating filing the heads down and drilling small dimples into the ends to help the metal flare out and create the rivet head as I tap it down.  When all the rivets were pounded flat, the ulu was pretty much done.  All that was left to do was touch up the colour and and antique the copper with the red wine vinegar and miracle gro solution.

The photo sequence below shows the progress of the ulu next to the original 1:1 blueprint that I drew from the reference photo.

The cleaver made a perfect blank
At this stage the antler has had very little work done to it, its naturally shaped like that
The blade has been cut and I started trimming the antler
The blade has been antiqued in muriatic acid and the musk-ox horn handle is planned out
I made the first cut on the musk-ox horn and started thinning out the antler part of the handle
All of the major shaping is done, it just needs to be antiqued and riveted
The finished ulu next to the original pattern

Photo Credits: Tim Rast

8 comments:

  1. Giving away all your trade secrets...now everyone will be making them!

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  2. As long as Future-Tim remembers that these notes are here and actually bothers to read them and save some future trial and error, then Present-Tim is willing to take that risk.

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  3. Sounds like potential for the creation of a rift in the space time continuum :)

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  4. Great work Tim, beautiful ulu! Your steel ones are just as great as your stone ones! Maybe try using some old saw blades next time, they usually need no antiquing, they are carbon steel, not stainless, (the steel the Old Time Inuit/Indians used) They should be plentiful up there, if not, they are easy to find-or buy 'em on Ebay, they are all over the place, the rusty old junkers sell for cheap, usually. I am jealous, your ulus are so beautiful! Actually, your work is one of my present inspirations, I make the steel ulus already, but always wanted to try slate and stone ones, now you inspired me to try some, they are coming along nicely, will have to post some pics soon.Also, if you don't have any handsaws or crosscut saws, get some circular blades and let 'em rust, it works, but the steel is so much better in the hand and crosscut saws, these are truly traditional, especially the older blades, typically better steel in those. Thanks a lot for the beautiful ulu pics!

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  5. Thanks, Frank - I've heard saw blades make good ulus - I guess I was stuck in the knife mindset because the original artifact was made on an old carving knife. But I bet the old saw blades would take the rust antiquing quite nicely.

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  6. Oh, ok, that's why you used the Chinese cleaver, that makes a lot of sense, if you don't have a machine shop (and most of the Native craftsmen/women probably didn't) you want to start with something as close to the shape and size of the item your making. It's interesting- you said the original was made from a carving knife, (I suppose that puts it in the mid 19th century to mid 20th century)They already had a functional knife, yet the person went to the trouble to turn it into an ulu, instead of using it as is. That says a lot about the deep rooted tradition of the ulu, and the fact that whoever made it, preferred using the ulu to a perfectly good Western style carving knife. Maybe it was easier to use for them (her probably) Yes, the old saws really take the old look well, if they aren't old and rusty already. I have some that are so pitted and rusty, I got a great deal, since they usually go for display, collections, etc. I make ulus and "old-time" style replicas, similar to what you make, except yours are MUCH prettier! Oh, P.S. just wondering -mhow much are the Dorset knife repros (the flint ones with the "polar bear" shape handle? God, I love those!

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  7. Frank D. is right when suggest using old handsaw blades. My sons and I make ulus (uliaq) for sale and for familyu members. The Yupik people of my my wife's family nearly always use hand saw blades. Hard to drill so we use a sharp punch and then drill the hole clean. My father in law used a two stem handle and small blade. Te stems were usually large nails split partially with a hacksaw. I use a single stem ulu and use an iron ail or heavy brass rod split with a hacksaw. We use finishing nails, copper brads or braas rod to attach handles. Yupik women prefer hard wood or antler handles but tourists prefer ivory although it becomes slick with blood. We make a few large heavy ones for heavy butchering but most women prefer a more modest 5 50 6 in. wide blade and older woman like a much smaller one for sewing. Most ladies have a stone of fine grained sand stone they use to sharpen their ulus. When the men finish them they usually only beveled on one side. We still use a bit of trap spring and an antler tine to make crooked knives for men's knives. again bevel on one side and sharpened on on side. A very good carving tool to creat wooden or baleen implements. We also make & use hand adzes with steel blades. I also us Tlingit or Haida styled adzes and crooked knives to carve wood.

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  8. Thanks Richard for sharing that. I like the tip about splitting nails lengthwise for stems - I'll have to keep an eye out for that in collections. The single sided bevel is the norm in the east as well.

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