Author Topic: Questions on new bow tillering (9/9) - at end of thread  (Read 12066 times)

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Offline Davepim

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Re: Questions on new bowstave (please look at my first tiller)
« Reply #15 on: August 28, 2009, 11:39:29 am »
The bow is not bending at all yet, so no advice is useful at this point. Next time, don't install your horn nocks until the bow is tillered, as you may end up being whip tillered. Wait and do your nocks at the end. Cut temporary self nocks, and they will disappear when you cut your tapers for the horn nocks.

Quite right adb! Also I think the tillering bar is too short - needs to be about your own height, that way, if you don't have a pulley system to draw the bow, then at least you can use your own bodyweight to do it!

Dave

Offline Marc St Louis

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Re: Questions on new bowstave (please look at my first tiller)
« Reply #16 on: August 28, 2009, 05:50:36 pm »
You need to shorten your string till there's no slack.  You need to remove wood in the center and leave the outer limbs alone for now
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Offline markinengland

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Re: Questions on new bowstave (please look at my first tiller)
« Reply #17 on: September 01, 2009, 05:06:03 pm »
I guess it doesn't need stressing too much but go really careful with the big knot. It looks as though the limb is almost all knot at that point. A knot has relatively little strength. If it goes at that point it may go very suddenly.
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Offline swotavator

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Re: Questions on new bowstave (please look at my second tiller 9/8/09)
« Reply #18 on: September 08, 2009, 01:41:33 am »
Hey all,
did a little work, and have tillered again.  This is the result.  I think that the left side is a little stiff, and something is going on in the center of the bow.  Any ideas how I can remedy?  Which numbers?  Thanks guys

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Offline Davepim

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Re: Questions on new bowstave (please look at my second tiller 9/8/09)
« Reply #19 on: September 08, 2009, 04:43:01 am »
Hey all,
did a little work, and have tillered again.  This is the result.  I think that the left side is a little stiff, and something is going on in the center of the bow.  Any ideas how I can remedy?  Which numbers?  Thanks guys

Ok, so you need to have the centre of the bow absolutely horizontal on the tiller bar to make any sense of it. You have too much bend between 10 and 11, and you need a tad more bend at 12 to alleviate this. The centre is too stiff between 6 and 9; start by reducing the depth between 8 and 9. You have what might be a hinge starting at 3, so you need to get a bit more bend at 4, not necessarily by reducing depth here; maybe width, but it's hard to tell from a photo. You've done well to leave a bit more timber around the big knot; this is the point at which the bow should start bending on that limb so it takes more stress than any other point - I still think it will be a miracle if the bow holds together at that knot! Remember that the way a bow bends round on the tiller bar is a combination of depth and width; we can see the depth from the photos, but cannot see the width, so you have to go with your intuition here. take it carefully and remember that, if this is your first bow, it may not come out perfectly - each bow you make is a learning experience,

Good luck! Dave

Offline adb

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Re: Questions on new bowstave (please look at my second tiller 9/8/09)
« Reply #20 on: September 09, 2009, 12:14:45 am »
Get rid of that long string!

Offline swotavator

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Re: Questions on new bow tillering (9/9) - at end of thread
« Reply #21 on: September 10, 2009, 06:45:36 pm »
Thanks for your help dave! - I made a shorter string too and have tillered it to about 2/3 draw.  It is still really heavy, and has about a 1.5 inch string follow now. 
My newest problem is that the bow seems to want to twist when i pull it to longer draws.  The bow has a really straight profile when looking at the back, and the string nocks are very deep and even. 
What could be causing this, and how to correct?
I was thinking that removing wood from the belly opposite the direction that the back leans.
The twist isn't huge, but is evident when I draw the bow, and was enough to split my tillering stick.
I am getting a new stick now, and am wondering if I can correct the twist by making the tillering slot VERY tight and leaving the bow drawn for a period of time. 
What do you think?

Offline Pat B

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Re: Questions on new bow tillering (9/9) - at end of thread
« Reply #22 on: September 10, 2009, 11:50:57 pm »
Feel the thickness of the limbs with your fingers. Use your thumb and forefinger and slide it up and down the limb and also across from side to side. If it is twisting as you draw, one side is thicker than the other. This will also teach you how to tiller a twist out of a limb.  ;D
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC