Primitive Archer
Main Discussion Area => Bows => Topic started by: Don Case on July 28, 2013, 01:47:24 pm
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Hi All
I live on Vancouver Island. I'm 67 and this is the first bow I've made since I was about 12. Somewhere in the last few years I picked up a fascination with Ocean Spray so I cut a couple of staves? from the bush out back and stood them in a corner of the garage for a year or two. My granddaughter recently took up archery so last camping trip I took one of the staves with us and started whacking on it with a hatchet. It is incredibly hard. Anyway here is a picture of my progress. The bow is short-50" NTN. In the picture it is drawn to 14 1/2" and my fishing scale says 26#. I'm a bit leery about where to go next. My gut says to thin the tips but I'm not sure. To my old eyes the sides look pretty even. So this is why I joined this group. Could I get some advice? Be brutal- I'm thick-skinned.
Thanks
Don
PS Thin end is to the left and now that I've posted it, it doesn't look that even
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Don, the tips look a bit stiff but it is hard to say without seeing the unstrung bow. What draw length do you want?
Jawge
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You don't need to get the tips that thin to make a good shooter with OS. If you can get them NARROW without letting them bend too much or let them warp off to the side do it. If you slowly perfect the tiller you can get that bow to at least 23" of draw. OS is seriously tough stuff.
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I'm not sure of the draw length but it should be about 24-25". Zion says max 23" so maybe I'll shoot for that. It's got about 1 1/2" of set but I didn't measure it when I started. It's looking like this bow will be to short for my granddaughter so I will just use it as a learning stick. I was thinking about a final DW of about 25# so I have a lot of wood to remove. As I was tillering and flexing the bow the bark cracked and flaked off the back of the thin end in a couple or three spots. The wood looks fine but I'm wondering if I'm pushing too hard? How do you decide whether to take wood off the belly or the sides?
Thanks again
Don
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From a guy that's the same age, I make my major adjustments with belly tillering, and very fine "tweeks" with side tillering. A single scrape on the belly is worth 8 on the sides. ....."twice as wide is twice as strong.....twice as thick is 8 times as strong"..... Your Bow looks good to me, especially since you have plenty of wood to finish "shaping" your bend.
rich
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The type of wood with the lenth of the bow uselly determs how wide I make my limbs. I shape the limb and get them straight before I tiller and never touch the sides again. I know some people do trim the sides if they get the even tiller early. And are afraid to lose it. But shaveing the sides down this but exture stress on your limbs.
Keep takeing the wood from the belly ,tillering untill you get the right lenth and right draw weight . This takes akes stress off your limbs the closer you get to where you want to be.
With the tips I make mine as small,narrow and as light as I can with out them beening the last 4 inchs..
Your bow looks perty good the right limb beens a little more than the left.
Juyst tiller it back to where your granddaughter can shot it. Just becuausw ZOIN SAYS MAX IS 23 DOS'NT MAKE IT SO. I'VE MAKE 50 INCH BOWS DRAWING26,27 AND AS FAR AS 28 INCHS.
WHO IS ZOIN ANYWAY
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WHO IS ZOIN ANYWAY
Second reply to my post and http://www.primitivearcher.com/smf/index.php?topic=35142.0
If I can do anywhere near this I will be a happy camper
Don
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WHO IS ZOIN ANYWAY
Zion is a young fella that lives out in the PNW that not only has OS around his area, but has actually used the wood to good effect. He didn't say 23" max, he said at least 23". Big difference.
For just getting back into it, that's looking pretty good Sir! I would guess that would easily make 25" if you get the handle workin just a bit. Josh
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if you get the handle workin just a bit. Josh
Would you mind giving me a little more detail on "get the handle workin just a bit"? Should I make the handle a little smaller? shorter? a little shorter on the fades? Keep in mind I've never done this before.
Thanks
Don
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if you get the handle workin just a bit. Josh
Would you mind giving me a little more detail on "get the handle workin just a bit"? Should I make the handle a little smaller? shorter? a little shorter on the fades? Keep in mind I've never done this before.
Thanks
Don
He means to get the handle bending with the rest of the bow this will give you a longer draw then having a stiff handle
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So I would take a little off the belly of the handle?
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Sure, what I mean by that is make the handle a working part of the bow. I usually wait until the last couple of inches of intended draw length and then start removing wood from the belly of the handle. For instance, if the intended draw length is 25", I would tiller the bow to 23" and then start gradually removing wood from the belly of the handle area. You really don't want the handle bending as much as the limbs because this is the worst possible place for set. Ideally, you should just start to feel the handle bend at about 23" of draw. Even with that slight of a bend in the handle, it will go along way towards relieving the stress of the entire bow. This will help considerably in getting the longer draw without excessive set. Josh
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How long is the handle? If its more than the hand and arrowpass you could always move the fades in a bit and gain a little"working limb".
Just be careful about the right limb just out of the fade,its a bit softer there and its easy to get a hinge in that area.
I see Gun Doc beat me to it :)
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The handle is 5" and the fades are about 4".
Don
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Whoa guys, i said AT LEAST 23" i never said it was impossible to get it to 24-25," i know what Os can do, so calm your horses, and crooketarrow next time read my comment thoroughly before saying something that isn't even true please.
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As I was tillering and flexing the bow the bark cracked and flaked off the back of the thin end in a couple or three spots. The wood looks fine but I'm wondering if I'm pushing too hard?
Any comments about this?
Thanks
Don
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Sounds like possible cambium peeling up, hope so anyway.
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As I was tillering and flexing the bow the bark cracked and flaked off the back of the thin end in a couple or three spots. The wood looks fine but I'm wondering if I'm pushing too hard?
Any comments about this?
Thanks
Don
It will pop off sometimes. I built one for my son, and the bark never cracked, I built one for his friend and all of the bark popped off. I think it just depends on the stick.
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If the wood was harvested in warmer months then the bark has a good chance if popping of. If you harvest during the coldest part of the year then the bark is far less likely to do so.
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Here it is again after a couple days of tillering. For this photo I made a new tillering stick and put the bow on it with the intention of pulling it to 24" but I counted wrong. Here it is drawn to 27" OOOPS! I have misplaced my scale so I can't give you a weight. I think I see too much bend on the right hand limb. Does overdrawing it once do much damage? It had 3" of set after this but it's slowly straightening out to its normal 1 1/2". Comments please.
Thanks
Don
Forgot the picture!
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WOW!!!! .................that sure is some bend. :o
Ocean spray is some real tough stuff. what does the un brace profile and the back look like???
Wow I'm speechless
DBar
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Letting it sit on the tree drawn to 27 inchs is a bad idea I use a tillering tree for early tillering only because letting it sit full drawn is gonna cause more string follow.
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Here's the unbraced and back. The back picture ain't that great, maybe you can see what you want. It was only drawn to 27" long enough to take the picture. I think I may have strained it a bit as it's staying at about 2-2.5" I found a smaller scale that only goes to 25# and the bow hits that at about 21" draw. Probably not bad for a child.
Don
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The outer parts of each limb need to bend more
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Live and learn..... bout time to start another one, don't ya think? Can't build to many! :)
DBar
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Definitely time to start a new one but that was the only seasoned stick I had. Now I have to wait a few months for the others to dry. I plan on making this one to death. I want to try heat treating, apparently OS responds well to that. I want to narrow the tips to see what that does. I should probably practice shooting this one. I hung the broad side of a barn in the front yard and I couldn't hit it. I also have to learn to make arrows. I should be able to fill the time til a new stave is ready. Then I can collect more so I won't run out again.
Don
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Over drawing causes set, chrysalls or breakage. Jawge
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Sounds like you got plenty to do......Have fun and enjoy makin shavings
DBar
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The outer parts of each limb need to bend more
I used a tillering block(the block with a pencil screwed in it) and at 23" it was even. That's as far as I went. I noticed that as I was tillering that as I increased the draw the first part that the pencil hit was the outer limbs. I think this means that as you increase the draw the outer limbs need to be thinned more than the inner. I think the outer limbs are looking stiffer because I over extended the bow when I drew it to 27".
Don
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Woah! Thats a heck of a bend!
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Over drawing causes set, chrysalls or breakage. Jawge
It is definitely taking a set. What are chrysalls? I think I will recognize breakage.
Don
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You could try heat treating. if you heat treat it lightly a few times it will do wonders, probably won't have any set when your done. make sure not to try to reflex the limbs too much at once or it will chrysal because the belly fibers are used to bending the other way. Tiller looks great, well if it didn't it would be broke haha! Chrysals are little cracks that appear on the belly if it is overstressed, but there's a few other reasons they can appear as well.
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Chrysalls are also known as compression fractures. They appear as faint, lines that run across the belly. They happen when the wood can't handle being compressed anymore so a small fissure forms where the cells are collapsing. That's my understanding, anyway. They are bad news and often spell doom for a bow though there are drastic measures that can be taken to alleviate them. If they are localized then they show that the bow was poorly tillered and if they are spread evenly along the whole bow then it shows a design problem.
My opinion is that you not only asked too much of that bow but you also weren't able to distribute the bend evenly enough. the outer limbs aren't doing their share. I'd chalk it up to experience and get started on your next one. Good luck and have fun.
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Yep chrysals can be seen by holding the limbs up to a bright light what they are is tiny little lines that indicate slight compression failure it's basically Little collapses on the belly
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Yup, I've got a few chrysalls. On both limbs and right where it bent too much when I overbent it. Looks like this bow is finished. I learned a lot. Next one will be better. Meanwhile I'll practice with it til it breaks.
Thanks for all the info and help
Don
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Lots of bend in that baby, I agree that you can get a short stick to bend out to 26/27/28 cause some here have done it but as a rule and especially for beginners
I use ,double the draw I want + the non bending area for a fairly safe build. Bending handle double the draw is pertty safe. As far as the bark cracking,I have never had much luck leaving it on,it always cracks after a while,I always take the bark off on any bows I am building,of course I have never used OS so can't say for sure on that. :)
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When a bow breaks, is it usually the back or the belly that causes it? Or is the jury still out?
Don
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I'd say that technically the bow almost always breaks at the back. That being said, the belly can fail in a way that forces the back to break. You can also have the bow crack and break in the middle of the limb, between the back and the belly. But I'd say that a good rule of thumb is that if the bow really and truly breaks then it was a failure in tension (the back) and if the bow takes excessive set or chrysals then it was a failure in compression (the belly). But that's a bit of an oversimplification.
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The outer limbs are doing plenty of work. it just looks like the fades are doing more work because of the extreme bend. Look at each limb seperately.
You did a great job of the tillering, all you have to do is get a little longer piece. Great work tho.
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The outer limbs are doing plenty of work. it just looks like the fades are doing more work because of the extreme bend. Look at each limb seperately.
You did a great job of the tillering, all you have to do is get a little longer piece. Great work tho.
Thank you Zion, I appreciate that. If there was a way to speed up the seasoning of the staves I collected 2 weeks ago I would be tillering instead of typing.
Don
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I agree with Zion you did an awesome job tillering in fact it almost looks perfect to my eye
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Thank you Joe. I was reading a thread about putting a thin layer of ipe on the belly of a bow that had some chrysalls. I had never heard of ipe so I Googled it and discovered that it is also called Brazilian Walnut. Hmmm, I used some of that on one of my model boats. I ripped out a couple of 1/16" or so pieces and glued it on the belly. The glue is drying right now. I can start tillering tomorrow afternoon!
Thanks again
Don
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that might solve your problem, if your glue holds the only problem that COULD happen is for the ipe to overpower the OS, but with the tension strength of OS i doubt it. Cant wait to see it.
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It looks pretty good. It will be nicer to shoot if you thin the width but leave the last 4" not bending. That way it will have very low handshock. It is a low lb. bow but do that on your next one. No one can ever make just ONE :)
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that might solve your problem, if your glue holds the only problem that COULD happen is for the ipe to overpower the OS, but with the tension strength of OS i doubt it. Cant wait to see it.
I waited 5 days for the glue to dry and then started tillering again. At 21 inches it was fine. At 22 I got a chrysal on each limb, one just outside the fade and the other at about halfway out. I wish I had marked where the original chrysals were. I would guess that the OS overpowered the Ipe or that the Ipe was a crappy board. Anyway I'm now stuck waiting for my new staves to season and my wife has an exotic garden stake.
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I've never done lams nor have I worked with ipe but my understanding is that ipe is incredible in compression but that it is relatively brittle and there for not particularly well suited to extreme bends. So I think that your chrysals came from the ipe's lack of elasticity. Sorry to hear that it didn't work out.
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My mom does the same thing with my broken bows ;)
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When I cut the strips I cut three so I could pick the two that were closest in thickness(my table saw ain't much). They were 27" long, 3/4" wide and 3/32" thick. I took the left over piece and bent it around til the ends were about 3" apart before it broke into three pieces. I don't think I can blame the chrysals on faulty Ipe.