Primitive Archer
Main Discussion Area => Bows => Topic started by: bigcountry on August 03, 2008, 07:40:18 pm
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Ok, I am trying to work on this yew stave I got. It had alot of windshake damage but I think I made the layout to miss it all
Not the best stave in the world, but something to work on. While bandsawing, the log twisted on me, and about 3/4 way up a limb, I got it too deep. I figured I could leave it thicker there.
Anyway, where should I go from here? Should I smooth/round the edges of the sapwood? Anyone have some rough dimensions to take more off the belly side? I am trying to follow the TBB1 yew bow. They have 1" handle wide, 1.25" handle deep, 4" from handle to fades, 1.25" wide at fades. And going to 5/8" tips. I want to band saw some more belly before rasping and floor tillering. But I need some safety lines
I want it to be 55-60lbs at 29" draw. Its 70" Tip to tip now. I am pretty open to design. Most likely a d-cross scection or flat D.
(http://i301.photobucket.com/albums/nn73/bigcountry_ky/YewStave/YewBandsaw2Topview.jpg?t=1217802064)
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Here's a side view
(http://i301.photobucket.com/albums/nn73/bigcountry_ky/YewStave/Yewsideprofile1.jpg?t=1217802425)
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Here's where I got too deep where the stave twisted whil bandsawing
(http://i301.photobucket.com/albums/nn73/bigcountry_ky/YewStave/Bandsawtoodeep2.jpg?)
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Here is a belly view where I let the stave twist on the bandsaw.
(http://i301.photobucket.com/albums/nn73/bigcountry_ky/YewStave/Bandsawtoodeep3.jpg?)
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Big,
Whats your sap wood depth on that?
SJM
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Sapwood is about 3/8ths of an inch. The pure white stuff. But seems to fade into the heartwood
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If it were me I'd work the sapwood down to 3/16 to 1/4"
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From now on I would only use a good rasp and scraper. A band saw can make 2 lil bows out of that before you know it. You could take the sap wood down a bit also. Pat
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that there is exactly why i only use hand tools when making bows.
that and the fact that i dont have enough bow wood to take that kind of chance with
good luck with it,your asking the right folks for advise
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I would take the sap wood down as well. Its a bit much for the weight bow you are making. Its not that hard to chase rings in yew. Yew ( ;) I mean you) sorry for the pun, its early.......just need to use a shap cabinet scraper and go real slow, one ring at a time.
As far as the bow design goes. I would make a nice bend through the handel elb out of that piece of wood. It looks nice and straight and would certainly make a nice one. That saw mishap may cause you some problems though it looks pretty deeply cut into the profile.....if its not to bad you could use that angle to then make your D section. Its hard to tell from the photos. For a nice elb blank try this.
Centerline 1 1/8", 5" out 1 1/8", 10" out 1", 10" out 7/8", then taper to the tips to 9/16". For the depth make it easy and go centerline 1", 5" off 1", 10" off 7/8", 10" off3/4" then taper to 9/16". Get the bow to that point with square edges then round your D belly and ease the edge of the back nicely. That "should get you a nice bending start. The rest will be tillering. You may need to shave the whole thing down a bit once you start the tillering process.....that will largley depend on the wood. This lay out should give you a bit extra meat in case you need it.
Understand that you need to look at those numbers as a staring point for your design. Every piece of wood is different and will behave differnt. Every bowyer works differntly. If I had that sitting in front of me that is how I would lay it out.
SJM
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ps.......you are way close enough to a finish bow that you should jsut use hand tools.
SJM
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ps.......you are way close enough to a finish bow that you should jsut use hand tools.
SJM
This stuff is strange to work. I tried using a draw knife on the belly, but it cut in and then would pull up other word. I tryed a ferriers rasp and would do great on the sap but heartwood wouldn't touch it. I then tried my nicholson 49 and it works ok.
so you guys think I should rasp off an entire 1" of wood from teh tip? Not cut anymore?
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PATIENCE will make a bow. Impatience makes firewood! ;D You could reduce the tips with your drawknife but go slow. Use your #49 on the sapwood then a scraper to try to get as close to one ring as possible. With yew, you don't have to get to one ring as long as the violations aren't too bad. Do the sapwood removal first before you reduce the thickness of the tips. I prefer to leave the tips thick until the tillering is complete then reduce them so they just don't bend. I leave the handle area full width and thickness until tillering is done also but it is too late for that now. Pat
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I need to get a vise or finish my shaving horse to work down the sapwood. I have a spokeshave I can try to use on the belly.
I am just shocked it works so much different than osage or hickory. I figured it would draw knife like hickory.
Maybe my drawknife is too sharp.
I figured I would scrape only on the sapwood.
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The 3 best tools for working yew are drawknife (used properly it will removes small almsot tranparent shavings of wood), Cabinet scraper and 36 grit sand paper. I usually tiller my yew bows with just sandpaper. Its a finicky wood that looses weight real fast.
The trick with the draw knie is to have it very sharp and use it very very lightly.
Osage = rasps
Yew = sharp drawknife
SJM
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With the bevel down you will have better control with your drawknife. Pat
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With the bevel down you will have better control with your drawknife. Pat
Oh yea, I always use the bevel down on any wood. But here's what I notice at least my yew stave. Never seen this on hickory or osage. When it cuts in, it acts like a wedge (like when splitting a stave) and instead of cutting the yew after 1/4", it lifts up thru the grain wood in front of it and causes problems. Kinda like my yew is very dry or splits easy. Maybe my drawknife is too thick. Just never worked with wood like this.
I have patience. just trying to find the right tool for the job. Looks like I am stuck to rasping.
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Big,
LOL.....as a bowyer you will spend more time rasping then doing anything else. Embrace it, love it and become one with the rasp. ;)
With a 49 and 50 you can take a bow from 1/4 splt to just about finished. Allot of guys do just that becase they do not have bandsaws. You will be amazed at how much wood you can remove with a #49.
SJM
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Little update. I have rasped and rasped until I can't rasp anymore. I got the profile, thined the sapwood, and rounded the belly. Starting to bend a tad. I haven't put a long tiller string on yet. But I came across this. I dug at it, and couldn't believe the hole.
Should I fill it it with super glue and saw dust? Or just fill it with superglue. Its in a critical place. Right above handle area into fades. This bow with have a semi working handle.
(http://i301.photobucket.com/albums/nn73/bigcountry_ky/YewStave/IMG_0012.jpg?t=1218332718)
Here is the "back" where this hole comes out.
(http://i301.photobucket.com/albums/nn73/bigcountry_ky/YewStave/IMG_0013.jpg?t=1218332966)
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Had some ugly knots. I just gave them a wide berth until I can figure out what to do with them. Not sure if should dig these out and fill with something or just leave em alone.
(http://i301.photobucket.com/albums/nn73/bigcountry_ky/YewStave/IMG_0015.jpg?t=1218333013)
(http://i301.photobucket.com/albums/nn73/bigcountry_ky/YewStave/IMG_0016.jpg?t=1218333088)
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So, here's where I am at. Getting excited to get past floor tiller.
(http://i301.photobucket.com/albums/nn73/bigcountry_ky/YewStave/IMG_0011.jpg?t=1218333194)
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I would dig out what you can of the pithy stuff in the hole add a bit of super glue and sawdust let that set and do another layer and so on until it is filled. Take it a little at a time so all of the saw dust is well saturated and let it set hard before adding more.
On the belly you shouldn't have to worry about leaving the surrounding wood proud but do on the sides. I also add super glue to all knots whether they need it or not. Pat
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Thanks Pat. Could I also use epoxy and sawdust since this is in the working part of the fade?
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If your draw knife is gouging try working it the other direction. A draw knife will always try to follow the natural grain dips and dives in the wood. Yew is a very soft wood and I have found it works easily with a good sharp scraper.
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The 3 best tools for working yew are drawknife (used properly it will removes small almsot tranparent shavings of wood), Cabinet scraper and 36 grit sand paper. I usually tiller my yew bows with just sandpaper. Its a finicky wood that looses weight real fast.
The trick with the draw knie is to have it very sharp and use it very very lightly.
Osage = rasps
Yew = sharp drawknife
SJM
thats sounds like good advise, i'll have to remember it.
i have a pretty nice yew stave that i plan on working come winter time
tim
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I think the only way to get epoxy to work would be to heat the bow and epoxy so it will flow. I have never used epoxy for this but plenty of folks have. I like super glue because it is thin and gets into small places without having to manipulate it with heat. Pat
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If your draw knife is gouging try working it the other direction. A draw knife will always try to follow the natural grain dips and dives in the wood. Yew is a very soft wood and I have found it works easily with a good sharp scraper.
I keep hearing that yew is very soft, but this stuff was tougher to work than osage or hickory. It laughed at my ferriers rasp, and my nicholson 49 was the only thing I found to put a dent in it. It was like very hard and brittle. It was so hard and brittle that when you used a draw knife, and cut in, it would start lifting ahead of the blade.
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I think the only way to get epoxy to work would be to heat the bow and epoxy so it will flow. I have never used epoxy for this but plenty of folks have. I like super glue because it is thin and gets into small places without having to manipulate it with heat. Pat
Thanks again Pat. I didn't know if superglue would flex or be brittle and break after some time.
I didn't understand what you meant in another reply when talking about the knots. You said, "On the belly you shouldn't have to worry about leaving the surrounding wood proud but do on the sides". Do you mean, I should just rasp the knots down on the belly but give them alot of woods on the side of the bow? I figured they would be weak points. I guess I will see them as stiff places when I tiller.
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If your draw knife is gouging try working it the other direction. A draw knife will always try to follow the natural grain dips and dives in the wood. Yew is a very soft wood and I have found it works easily with a good sharp scraper.
I keep hearing that yew is very soft, but this stuff was tougher to work than osage or hickory. It laughed at my ferriers rasp, and my nicholson 49 was the only thing I found to put a dent in it. It was like very hard and brittle. It was so hard and brittle that when you used a draw knife, and cut in, it would start lifting ahead of the blade.
Is your stave still green? It will pack up most rasps in a hurry if its green. I havent found any wood, even the hardest woods like seasoned hickory that I couldnt work with my fariers rasp. After all it was designed to cut horse's hooves.
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I guess you will leave a little "meat" around a larger knot on the belly just so it doesn't over stress there but if you leave too much around the knot the area, on either side of the knot will be more susceptible to over stressing.( ??? ::) ) A evenly bending limb is more important. The stresses are shared by the entire limb. That is why I add super glue to most knots to help support the knot and surrounding wood.
I have not dealt with an area as long as your knot is so I don't know as a fact it will work. This is how I would handle the problem. Experimentation is a part of the process of wood bow building. Pat
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Is your stave still green? It will pack up most rasps in a hurry if its green. I havent found any wood, even the hardest woods like seasoned hickory that I couldnt work with my fariers rasp. After all it was designed to cut horse's hooves.
Ryno, she is very dry. She has been drying out in WA state for a few years. Almost wonder if she is too dry.
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I guess you will leave a little "meat" around a larger knot on the belly just so it doesn't over stress there but if you leave too much around the knot the area, on either side of the knot will be more susceptible to over stressing.( ??? ::) ) A evenly bending limb is more important. The stresses are shared by the entire limb. That is why I add super glue to most knots to help support the knot and surrounding wood.
I have not dealt with an area as long as your knot is so I don't know as a fact it will work. This is how I would handle the problem. Experimentation is a part of the process of wood bow building. Pat
Hey pat, I heard you used all kinds of terms when you built your yew bow. Like Hoopdy or something like that. Is this what you are referring too? Is it pretty normal to see a small pin knot on the sap to be like this? Just trying to learn more about yew.
I have did a two part approach. I put crazy glue in to fill in the real fine places and epoxy with sawdust in where the gaping hole is.
I was looking at this this morning and don't think it will create much issues because runs the length of the bow and lot of wood on either side. Well, time will tell.
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If you look at the pic on post #19 you will see how the sapwood makes a "hoop-t-do" above the knot. This is natures way of strengthening the wood around the limb (knot). The belly should follow, to some extent, this wave in the sapwood. Usually on the back there is enough "natural" meat so an island of extra wood is not needed and can cause problems as they are basically a violated ring. On the belly some "island" of wood will be necessary but that is different in each piece of wood. What you want is a good even bend throughout each limb. Any extra wood left on the belly can cause a stiff spot in the limb.
What I call hoop-t-dos are up and down waves in the surface of the stave. Snakes go side to side. When you get hoop-t-dos and snakes you really got something! ;) Pat
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Ok, I have got the bow floor tillered but its stout. I put a tiller string on (One you don't have to cut in nocks) and pulled about 4". I am not sure this bow should be braced yet even 3". She seems to want to twist some. Should the bow be stiffer side way? I rounded the belly.
I never faced this on my flatbows. But this by is 1.25" at fades by 1" thick going to 1/2" tips. I suppose the thickness should be less than the width? I kept the back completely flat. Maybe I should start flattening the belly some. She is stiff. I bet around 80lbs or more now. I just don't want to go too far with the belly and get a lightwieght bow.
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Yeah what every one else said.
1. Reduce that back with a scraper to about 1/4 to 3/8". Go slow.
2. Wrap that bandsaw "oops" with a couple layers of Electricians tape. (I do this to remind me where not to scrape.)
3. Work the belly down with scraper and rasp till it floor tillers good. Then remove the tape and work on that section.
4. Switch to scraper and sandpaper only for final tiller.
For rounding the belly, I like to use the old "Chattanooga shoe shine boy" method of sanding, with coarse grit emmory cloth. (a
sanding belt works well too)
That is a nice looking stave and should make you a mighty fine bow.