View Full Version : making a saya ?
01-16-2013, 05:11 AM
I'm looking at doing a little woodwork. I was wondering what the traditional knife saya construction is/was. Is it split then chisel out one side, split chisel both sides equally or I saw one where there's 2 equal sides and a middle section cut out with the knife shape> ? Or is it all preference? And due to ignorance, is the pin only going about 1/2 way through ?
I recently figured out there's a place I drove by 6 days a week for bout 2 years that sells wood and knife making materials and I wanna finally check into them. I figure it's a good starting place. Thanks
01-16-2013, 10:41 PM
all of the above. the pin goes all the way through. The fastest an least time consuming is to do two flats and add a center piece. The most elegant and hardest to do is the split and chisel method. It is very traditional and you can fit it perfectly for a tight friction fit. neither is wrong. It is the skill set you bring to the table that determines what you want to do. Learn them all. I carve out two pieces with my pocket knife or bird's beak paring knife and then match the sides and glue. If the knife doesn't fit after glue up, I take a small heated wire and burn the spots that are preventing the fit. Hope this helps.
01-18-2013, 06:43 AM
Go to your wood store and look for some thin stock exotic wood. I've used Bolivian Rosewood and Macassar Ebony with good results and a wax finish. Stay away from woods that will ooze pitch or sap. I tried Spanish cedar and it coated my blade in pitch. I also have a piece of Wenge I'm waiting to use since it's fairly toxic I'll need to finish the inside of the saya and outside to prevent any splintering that could form over time.
So, take your thinstock and trace out 3 stencils of your knife profile. I use a silver Sharpie because it's easy to see under the light on the bandsaw and the width of the marker gives some room for error. It's best to leave 1/4" around the knife stencil. Take the piece your going to use for the center and cut out the center piece of the knife stencil. Be careful and cut slowly with your saw to avoid cracking the piece, you may need to make some relief cuts where the tip will sit on the inside. Once you have the center piece cut lay it on another single cut out stencil and see if your knife will slide into the center piece easily. You may need to make some adjustments with a dremel.
So, once you have a center piece that allows the knife to slide in easily, check the thickness of it. if it's too thick the knife will wobble in the saya. Reduce the thickness if necessary on a belt grinder and check often to ensure you don't remove too much material.
When it looks good, use some titebond II and glue the center piece to ONE SIDE ONLY. Use a number of clamps to apply even pressure on the center piece and one side. and then clean up any glue that oozes onto the inside of the saya with a Q-tip and Acetone. Do it quickly so its easier. Then let the two pieces sit overnight. Remember to unclamp the pieces after 30 minutes of curing.
Once the glue is dry, I take the piece and shape the profile of the saya's edge and spine. 1/8th inch of wood from the inside of the center piece to the outside of the edges of the saya should be good.
Slide the knife in the 2/3's piece and make sure it moves in and out nicely. I also take the 3rd piece and clamp it to the 2/3 of the saya and make sure the knife will move and out easily.
test out your drill bit and dowel on a scrap piece of wood to make sure the dowel fits in the hole properly. When you have it right, take the 2/3 saya with the knife resting inside of it and put the heel of the knife up against the drill bit on a drill press. Leave just a fraction of a fraction of an inch between the heel and drilled hole if you like, or at least for your first saya, you'll get better over time. Test the dowel in the hole on the 2/3 saya.
Now just take your third piece, or even just the uncut flat stock and glue it to the other 2/3's piece. I usually run a thin bead of glue on the center piece edge of the saya, if you use too much glue it will leak into the saya and potentially prevent the knife from going in. I usually use a Q-tip and spread the bead evenly, even cleaning the inner center piece edge of glue to ensure none will seep in when clamped.
Glue and clamp.
unclamp after 30 minutes and let it sit overnight or 12 hours. trim the edges of the 3rd piece you glued to match the 2/3's piece you made, sand, sand, sand. Fit the drill press into the pre-drilled hole on one side and go through the other piece. Make sure the knife goes in and out easily, ensure the dowel fits, and then add a coating of George's Clubhouse wax to the outside.
Another thing I like to do with my dowel hole is raise it up so the spine of the knife presses against the inner saya and the edge is free floating. You just need to make sure there is enough room when making the center piece and ensure there is enough wood around the dowel hole to support the weight of the saya or knife depending on how you carry it or travel with it.
01-18-2013, 12:39 PM
Thanks all, I went down to the wood store and picked up some Cebil. It has a nice slanted grain so everyone will think it's going fast ! :) Bad thing is I did some research on it and it says it's so hard it dulls cutting tools. I guess I'll just make it tight on the spine so it doesn't rock.
A great many hardwoods come with cautionary warnings about the dulling effect they might have on tools. You'll hear the same about some pieces of maple (burl in particular), most rosewoods, ebony and a host of others that come from South America to Africa to Asia. For a project as small as a Saya you don't really have to worry about this. Just make sure your tools are sharp to start with if the wood is dense...and be patient cutting with any power tools so you don't burn the wood with the resulting friction. Also - if not already addressed -make sure your wood is well dried and not green. The expansion and contraction of green wood could easily warp a thin saya as it dries.....potentially making it no longer fit your knife properly.
Now, to circle back to the original questions about what's traditional and how to go about making a saya- I'll throw in another "all of the above" for the three methods mentioned. The choice is as much a matter of taste and time as it is skill and what tools you have available. Any of the methods can yield a great result.
Personally, I've used a method similar to what Cascadification described and gotten good results. I've also taken a more traditional approach and carved a saya.
For me, I go with the 3 piece method when function is my first goal (And the above description outlines this method well). If I'm using really nice wood or making a saya for an heirloom grade knife....I go with a two piece carved approach....but only if I have the time which is not often the case. The reason for the two piece approach to keep the seam/glue-joint as invisible as possible.
Don't want to turn this into too much of a woodworking post but for a two piece carved saya - here's a quick outline of my process to make it:
1. Starting with a good block of wood around 3/4inch to 1 inch thick ....I split the wood on a bandsaw into two pieces. They could be split equally in width but my approach is to make the ratio 1/3 to 2/3rds because it's easier to do the carving almost entirely on one half then carve two matched pairs.
2. Second step, I plane the inner faces of both boards so they are flat and mate nicely to each other.
3. Next, I trace the outline of the blade onto a stencil and copy it on to the insides of both blanks. I'm careful to make sure the stencil is matched edge to edge for the entire block as this will be important later.
4. I'll rout/carve the cavity for the blade out of the wider board - leaving it a fraction proud at the blade's spine. In the carving process I'm also careful to cut a little extra depth around the cutting edge of the blade. My goal is to get a good pressure fit up near the spine so the cutting edge itself is not in contact with the wood.
4. On the thinner piece, I make the slight carving needed so my two blanks will sit well together. I'm aiming for a pressure fit so i don't want to carve too far or I'll lose that. for the carving i use a mix of basic woodworking chisels, some carving gouges or sometimes a dremel tool with a grinding bit. Depends on what kind of wood....my mood....and how delicate i need to be. It's not a difficult process but it takes patience and sharp tools to hand cut. If you overdo it you're sunk and will no longer have a good fit.
5. After i have things fit and the inside cavity is ready (carved/sanded) - I will put either a thin coat of shellac or butcher block oil on the inside of the cavity i created. (This is not traditional, I don't think....but the shellac is food safe and it keeps the wood from absorbing moisture and potentially warping. It is also a good barrier to keep any camelia oil put on a carbon knife blade from soaking into the wood...The shellac is a good protective resin....and it won't harm the blade or wood.) Oiling the wood inside works too... If you go ahead with the step just be careful and sure not to get any oil/shellac on to the surfaces you will be gluing together.
7. with the blade resting in the deeper cavity - and before gluing - I will mark and drill the thicker half for the pin. I can use this hole as a guide to position my drill to go through the other half after gluing.
8. time for glue. The two halves are glued together at this point.
9. since i went with a 1/3 vs 2/3rd split to make the carving easier. The thickness of the remaining wood on the two pieces may not be symmetrical at this point. I fix that with a planer...taking the thicker side down as needed to get the two sides about the same thickness. A jointer is ideal but this can be done by hand or with a grinder/orbital sander etc.
10. Next up - trace the stencil on the top of the now glued piece. (This is why it was important to make sure the stencil's outer shape matched up with the edges of my wood blanks.)
11. I'll cut about 1/4 proud of the stencil with a bandsaw. I do it by eye but for the detail oriented you could use a scribe or another tool to expand the stencil.
12. Last bit is shaping with a sander/grinder/file to taper the edges .... and sanding to the desired grit for whatever finish you intend.
Good luck with your saya project.
01-20-2013, 09:44 AM
Eamon uses a softer wood for the inside piece. The color contrasting stripe is kinda cool....
01-20-2013, 11:42 AM
...I was wondering what the traditional knife saya construction is/was....
Way to verbose responses you got here. :)
Traditional saya, is two piece saya, with cavity carved on one side. Three piece saya was "pioneered" by TC Blades a few years back and since copied by a few.
Here is how I make my (traditional) sayas.
-Bandsaw (if you resaw your wood)
- 6x48 disk/belt sand for squaring, flattening, and shaping
-Piece of marble top with sandpaper glued on for flattening halves for precise fit
- Bench Wise for holding a half where cavity is carved out
- Saya chisel/s- very important, will save you time. Other chisels don't work well. If you can't afford 2, get one in 3/8. Buy 5/8 at a later time. They are $150 at JWW, but you can buy it on 10% sale.
- Clamps or you can tightly wrap your halves with electrical tape. It will work.
Use poplar, cedar or straight grain redwood - soft woods, as woods like maple and even walnut are difficult to carve, and the more figure in the grain, the more difficult to carve.
Resaw the board, give it 24 hours to rest for working out the tension, then flatten. Secure the half for cavity in your bench wise. Make an outline of you knife with a pencil, and trace the outline with a cutter, making a 1/16 or so cut into the wood. Then with a 3/8 saya nomi tilted so you are cutting just with the corner of a chisel, carve the perimeter of the cavity, and then remove the wood in the middle. Important that you establish the direction of the grain and carve with the grain. You will feel that in one direction your chisel struggles a bit, and in another it doesn't - that' the direction. Also when you carve with the direction of the grain, you carve tip to heel, so you can apply a little more pressure and remove more material toward the heel, similarly to knife's geometry. Here flexing of saya nomi is invaluable. Careful not to run over your cavity perimeter. Fit your knife regularly, tilt the cavity half to the light to see the depth of carving , so you see where you have high points. Mark them with pencil and remove them. There is a little bit of a learning curve, but I would say, after carving 4-5 cavities, you will have a good idea.
Gluing. The reason you carve on one side is because wood will shift when glue is applied and you clam it, and aligning two carved cavities would be difficult as you have a small window of time and glue bonds fast. Apply glue on one side (cavity side), carefully align both sides, carefully fasten them with electric tap. Once you see that everything is aligned, wrap tightly with more tape. You can clamp over it or leave it just with a wrap (it has to be tight though).
Notice I don't give halves the shape of knife before hand. I need them to be stay rectangular to be able to to hold them in a vise and clamps.
Mark the location of the cavity on the outside with calipers, you know where cavity is after you glue the halves up. Put a knife over caliper marks, outline it, add some extra, and rough cut with a band saw. Then give the final shape with a sander.
Shaping is best done on a sander of sorts. 6x48 belt/disk is probably your best option.
You can be creative - give a saya distal taper, cut bevels and chamfers on the spine and then blend them by hand (cork block with coarse 80-100 paper works well). Finish saya to 320 grit by hand, best outdoors on a sunny day, so you see scratches better.
For finish, apply tung oil, let it soak a 10 min, remove excess and let oil cure for a couple of days.
PS: once you master softwoods, you can move onto hardwoods and highly figured woods. If done properly, you won't see a glue joint, so your saya will appear as one piece. I think it is worth to put in time and effort to learn this method over a shortcut.
01-20-2013, 11:59 AM
Some good tips Marko. Your attention to details comes through, even in your directions, lol.
01-20-2013, 07:11 PM
Some one posted this about 6 mo. ago. I fell in love with it. It is quite long but you get the general idea of a traditional saya.
Also I loved every saya that Eamon made that came my way.
01-20-2013, 07:25 PM
Funny that Marko mentions TC Blades, found this video on Youtube a little while ago:
01-21-2013, 12:42 AM
I stumbled on this the other day,
its for a sword not a knife, but interesting nonetheless
01-21-2013, 01:13 AM
I was going to mention there was a serious lack of pictures in this post.... :detective:
Until I saw the videos! Any WIP pictures?
Those TC videos are some of my favorites! :biggrin:
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