Author Topic: Maybe an idea  (Read 3028 times)

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Offline DC

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Maybe an idea
« on: May 19, 2016, 10:53:12 pm »
I'm working on my first bendy handle bow. I was trying to find a way to see if the handle was bending  just a bit. I remembered Del's idea of fixing the splints to the bow to check for twist so I glued a splint to the center back of the handle. When I bent the bow I could see both ends of the splint lift off the bow. I was happy. Then I thought, if one is good how about a bunch. So I cut a bunch of 6" splints and layed them on the back and glued one end with 5 min epoxy. Put the bow on the tree and when it bends the ends of the splints lift off the bow. You can see if it's bending evenly by the amount the splint lifts. This has probably been mentioned before but I haven't seen it so i thought I would mention it. I think it would work a treat on lumpy bumpy staves. The pic on the tree is blurry but I think you can get the idea.

Offline Jim Davis

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Re: Maybe an idea
« Reply #1 on: May 19, 2016, 11:52:14 pm »
Very revealing trick. Good thinking. The only drawback I can see is having to  remove all those glue spots after. Could get tiresome trying to protect all the sticks while doing some more scraping or handling the bow, etc.

 But I really like the concept.
Jim Davis

Kentucky--formerly Maine

Offline DC

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Re: Maybe an idea
« Reply #2 on: May 20, 2016, 12:37:56 am »
I tried just clamping the splints on but they moved around too much. I had to reduce the sapwood on the bow so a few scrapes here and there to remove the glue won't be a big deal. On something with a pristine back it may be a problem. It is 5 min epoxy so it doesn't stick all that well. I've only used it for a couple of turns back and forth to the tree but they really didn't get in the way. Once I get the bow braced and don't take the string off I'll see how much they get in the way. They aren't necessary on a smooth curve like this but this is what I was working on when I thought of it. Wish I'd thought of it at the beginning of the week when I was working that swoopy Cascara.

Offline Del the cat

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Re: Maybe an idea
« Reply #3 on: May 20, 2016, 02:07:11 am »
It's fun to try these things... a bit of "what if" is always good  :)
Del
Health warning, these posts may contain traces of nut.

Offline DC

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Re: Maybe an idea
« Reply #4 on: May 20, 2016, 11:16:27 am »
I was mulling it over as I dropped off last night. I think hobbie hot glue would work to avoid back damage. I think this would be a good way of noticing set and where it's happening. with equal length splints you will get arc of a circle tillering and if you shorten the splints as you go out the limb you would get elliptical. That's assuming the tips of the splints come off the bow the same distance. For someone like me who is still unsure of what they are seeing I think it will help. For anyone else it would probably be a pain in the ass. Whether or not it would help or hinder the development of the "tillering eye" I don't know. I'll leave them on this bow and see how it goes.

Offline Pat B

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Re: Maybe an idea
« Reply #5 on: May 20, 2016, 11:43:55 am »
Working a tillering gizmo along the belly will show you how the limbs are bending or not bending and also you can see twists by using the gizmo along the sides or the belly where a line from the gizmo would show stiff on one side and not the other. I'm sure we've all come up with ideas that work, some more complicated than others but if it works for you then it works!
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline DC

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Re: Maybe an idea
« Reply #6 on: May 20, 2016, 11:49:53 am »
On a straight stave the gizmo is the obvious answer but this will work on lumpy staves where a gizmo suffers.

Offline Lucasade

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Re: Maybe an idea
« Reply #7 on: May 20, 2016, 02:00:01 pm »
Blu tac? Or whatever the non-UK equivalent is called (other coloured non permanent adhesive putties are available...)

Offline DC

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Re: Maybe an idea
« Reply #8 on: May 20, 2016, 02:50:14 pm »
If Blu tac is that stuff for holding up posters and such it wouldn't hold the splints solid enough. They can't move or it throws you off.
 
The bow I am working on is my first ELB. I had a really nice thin piece of Yew and I've wanted to do an ELB. It was working beautifully with the spoke shave and I was enjoying that and playing with this idea that I totally lost track of what I was doing and tillered it out to 45#@26" on the long string :-[ :-[ :-[. It was a short long string so it wasn't totally the end of the world. I put a string on it and now it was a little whip tillered so I worked on the middle and ended up around 42#@ 28". Shot it and got in the high 150's at 10GPP. A little disappointing. I was planning on horn nocks but I might skinny the tips right out and see what I can do.

Anyway I'm off topic. I just like talking about how stupid I can be ;D The idea works. You can see the bend very nicely. What really impressed me was how well it showed up set. When I first glued on the splints the tip of them were touching the back. After I tillered for a bit I could see that each one was off the back by about 1/32" except on the portion of one limb that I had steamed a bit(small bit)of deflex out. The two splints in that area had lifted by maybe 1/16". Definitely showing more bend that I don't think I would have noticed in a million years. Once I remembered to put the right string on it and left it braced the splints started to get in the way. Now it was bent all the time the splints stuck up and snagged on things. Eventually I lost two of them. If I had braced it when I should have I probably would have popped them all off. I also think the bending loosens the glue so. Once off you can't really put them back because that messes the original position that shows the set so nicely. It needs some thought. I think I can tiller without it but I really like how well it shows the set. I struggle with that and in my humid climate it a constant struggle. Anyway thanks for listening. 

Offline Pat B

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Re: Maybe an idea
« Reply #9 on: May 20, 2016, 03:02:49 pm »
The stave you have pictured looks quite straight.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline DC

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Re: Maybe an idea
« Reply #10 on: May 20, 2016, 04:57:22 pm »
Yeah, it's a beaut. Just a bit of twist in one limb that came out easily. No knots. One little flaw in the back to spoil the prettyness. I didn't need any gadgets with this one. It was what I was working on. It sure showed the little bit of set.

Offline Emmet

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Re: Maybe an idea
« Reply #11 on: May 20, 2016, 06:59:42 pm »
I would think a small rubber band would hold a splinter fairly tight.
Good idea  tho, I can see it being a useful trick.

Offline DC

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Re: Maybe an idea
« Reply #12 on: May 20, 2016, 07:02:22 pm »
If you have a band around the bow you can't scrape the belly :(

Offline Academonicon

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Re: Maybe an idea
« Reply #13 on: May 20, 2016, 11:47:37 pm »
I do a similar thing but more low-tech - I hold a pencil flat against the handle with the bow bent on the tree, and run the pencil down each limb to see where the pencil tip gets closer to/farther from the bow.

Offline Emmet

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Re: Maybe an idea
« Reply #14 on: May 21, 2016, 11:31:19 am »
If you have a band around the bow you can't scrape the belly :(

Should be able to slide the band out of the way till your ready to recheck tiller