Author Topic: yew takedown  (Read 34184 times)

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Offline Weylin

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Re: yew takedown
« Reply #15 on: September 09, 2014, 11:07:09 am »
Richard, I think the knots will be fine. I would try to avoid leaving them exposed along the edge there, but it doesn't look like that is an issue from where they lie.  The thing you will need to avoid in order to have a durable long-lasting take-down is the stepped shoulder going into the sleeves.  It needs to be a smooth gradual reduction in width down into the sleeves.  Don't leave any shoulder, not even butting up to the brass.  This is tempting to do in an effort to make the surfaces of the brass and billet smooth, but it is better to leave the edge of the ferrules proud and smoothly run the wood into the sleeve.  I have seen a couple of yew take-downs develop lifted splinters when shouldering the joint.

+1

Offline Del the cat

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Re: yew takedown
« Reply #16 on: September 09, 2014, 11:42:38 am »
Good idea. Those are gorgeous yew billets and it would be a shame to ruin them due to inexperience. Get your hands on some inexpensive maple or hickory boards and have at it. Walk, then run.  ;)
He could ship 'em to me to look after in the meantime O:)
Del
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Offline Richard B

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Re: yew takedown
« Reply #17 on: September 09, 2014, 02:41:31 pm »
Carson,
Many thanks for that. I have seen a number of takedowns where  the belly and sides (to about half depth) have been shouldered, but did wonder about the longevity given repeated compression against the brass, so will take your advice and taper down to the inner brass sleeve section all round.
Interested that both you and Weylin do not think the knots will be a problem where they are in relation to the edge of the sleeve. I can see that they will be well away from the edge of bow and the back is free of any defects. They are quite solid from what I can see at the moment, but there is no knowing how they develop inside the wood before they are grown over, so is there not a danger that the bow will be weakened in an area of high stress concentration around the sleeve edge?

Offline steelslinger

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Re: yew takedown
« Reply #18 on: September 09, 2014, 04:03:05 pm »
My take-down was one of them that lifted a splinter.  I think if i do another one I will do some string wraps at the step to help with strength.

Offline Richard B

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Re: yew takedown
« Reply #19 on: September 09, 2014, 06:13:17 pm »
Steelslinger,
Did it lift a splinter on the back or belly?

Offline Richard B

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Re: yew takedown
« Reply #20 on: September 14, 2014, 07:12:42 am »
Just got a "Shinto Rasp" and started reducing my yew billets. What a brilliant tool! Used a surform for a lot of the wood reduction on my elm bow and this is a joy to use in comparison.  Fast wood removal and very precise with no danger of gouging out wood around knots. In the past I have used the edge of a saw for shaping wood (can work well but you need to develop a real feel for it, or it can be risky). By combining a whole lot of saw blades this tool seems to have turned this approach into something really useful.

Offline Richard B

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Re: yew takedown
« Reply #21 on: September 16, 2014, 03:17:05 pm »
One of my billets has about 25 degrees of prop twist. I am thinking of heat treating to correct + induce a bit of reflex to match the other stave (it is currently slightly deflexed). I have never tried dry heating bending wood before, or heat treating yew in any way. I have steamed other woods before (both for bow making and boat building) and feel more comfortable with this.
The stave is currently tapering from about 35mm thick out of the fades to 20mm at the tip.
What have people had more success with with yew?

Offline Carson (CMB)

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Re: yew takedown
« Reply #22 on: September 16, 2014, 03:48:02 pm »
I would use a good long steam.  As for the previous question, the splinters lift on the back of the bow where the grain ends abruptly at the shoulder. 
"The bow is the old first lyre,
the mono chord, the initial rune of fine art
The humanities grew out from archery as a flower from a seed
No sooner did the soft, sweet note of the bow-string charm the ear of genius than music was born, and from music came poetry and painting and..." Maurice Thompso

Offline DC

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Re: yew takedown
« Reply #23 on: September 16, 2014, 05:59:13 pm »
Yup, steam. Three days ago this 6' yew stave had over 90 degrees of twist. I made up a steam box that clamps to my caul so that I can twist it while it's still steaming. Thanks for the idea Del  :)

Offline Cloudfeather

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Re: yew takedown
« Reply #24 on: September 16, 2014, 08:42:24 pm »
DC, any chance of some building schematics? I've got some maple and pear wood with some serious twist that needs fixing.

Offline DC

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Re: yew takedown
« Reply #25 on: September 16, 2014, 09:03:50 pm »
Here's a couple of pictures. The box is a friction fit to the caul. I clamp the box to the caul and stuff the ends with rags. The strap wench works good and doesn't mark the bow(so far). The steam generator is a Conair fabric steamer that I got a the Sally Ann for $5 (Can). Holler if this isn't enough.

Offline Aaron H

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Re: yew takedown
« Reply #26 on: September 18, 2014, 05:11:05 pm »
Brilliant

Offline Prarie Bowyer

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Re: yew takedown
« Reply #27 on: September 21, 2014, 03:43:54 pm »
Grasp!  Smart!  Hmmm haw can I make that for mine?

Offline Del the cat

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Re: yew takedown
« Reply #28 on: September 21, 2014, 03:46:27 pm »
Woo that's a nice bit of kit :)
Del
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Offline Weylin

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Re: yew takedown
« Reply #29 on: September 21, 2014, 04:32:31 pm »
Interesting! I wonder if the steam loses any heat as it travels through that long tube.