Primitive Archer

Main Discussion Area => Bows => Topic started by: Muskyman on March 15, 2023, 01:19:21 pm

Title: Yew stave straightening
Post by: Muskyman on March 15, 2023, 01:19:21 pm
I got this as a present. Posted it before but now I’m thinking about starting a bow with it. Yew stave 73 inches long but will cut it down to 72. Has almost 2 1/4 inch bend and I’m guessing I should take it down to about floor tiller then try to straighten it. Couple other things I’m curious about are the knots and should I try to avoid them with my layout

Title: Re: Yew stave straightening
Post by: Muskyman on March 15, 2023, 01:20:55 pm
Knots
Title: Re: Yew stave straightening
Post by: Muskyman on March 15, 2023, 01:21:41 pm
Another pic
Title: Re: Yew stave straightening
Post by: bjrogg on March 15, 2023, 01:44:22 pm
Sorry muskyman I have zero experience with yew. I know it’s a different critter.

I would suggest watching the video Del posted a link to on his new years bow in the English war bows section. I watched it and it was quite informative

Del has lots of videos that would surely be helpful

Bjrogg
Title: Re: Yew stave straightening
Post by: PEARL DRUMS on March 15, 2023, 02:19:49 pm
That knot is well below any line your bow will take on. Yew will bend and stay. But, you want to over bend by at least 25%. The thinner and more flexible the limbs are when you heat it up the more likely it stays put. I'd thin the sapwood down to a 1/4" thick max before you start doing much else.
Title: Re: Yew stave straightening
Post by: Muskyman on March 15, 2023, 02:29:30 pm
I’ll try and find it.  I’ve never really straightened anything and am just a bit unsure as to how. I have watched others do it but, not really anything like this.
Pearl, I’m planning on trying to take it more to bow shape before I start trying to bend it. Planning on trying to make a jig of some kind before I start trying to do any straightening.. probably should get a few more clamps to.
Thanks again gentlemen
Title: Re: Yew stave straightening
Post by: Muskyman on March 15, 2023, 02:45:37 pm
Went to Del’s site and after about a minute I subscribed. He’s a yew wood guy for sure. I’m pretty sure I’ll sure I’ll find some help on his site, just need to go through some of his videos and find one on straightening yew staves. Great resource for bow building.
Thanks for that Bjrogg
Title: Re: Yew stave straightening
Post by: PEARL DRUMS on March 15, 2023, 03:03:30 pm
That bloke :) is on here often. I'm sure he will gladly chime in and help all you need. He is one of the old timers around here.
Title: Re: Yew stave straightening
Post by: Del the cat on March 15, 2023, 06:19:49 pm
First Yew bow of the year had a load of deflex and some knotty areas:- Here's the playlist
https://www.youtube.com/watch?v=dJvkD1ib4YI&list=PLBz2tD9476KTaf_X7Em-n2t7jv4i1kCqm (https://www.youtube.com/watch?v=dJvkD1ib4YI&list=PLBz2tD9476KTaf_X7Em-n2t7jv4i1kCqm)
And here's a post from my blog showing a knot that I managed to fill successfully on a 90# ELB
https://bowyersdiary.blogspot.com/2012/01/mystery-knot.html (https://bowyersdiary.blogspot.com/2012/01/mystery-knot.html)
Loads of youtube vids and blog posts on steam bending/straightening
Del
Title: Re: Yew stave straightening
Post by: superdav95 on March 15, 2023, 06:46:31 pm
Your in good hands here with these guys mike.  I’ve referred to dels in for for myself.  Good stuff.  I’ve got a similar piece of yew staring at me right now.  Best of luck. 
Title: Re: Yew stave straightening
Post by: Muskyman on March 15, 2023, 10:03:53 pm
Haven’t had a chance to watch the videos Del posted yet but, I’m going to be watching them and others on his site.. I did want to post a photo I took today of the bend in my stave.
I pulled a string down it to show the bend and where it lays.. it’s about 4 to 4 1/2 inches from the center of the stave to the string. I’m hoping that’s doable. I did watch one of Del’s videos where he bent one in the handle section so I feel like I can bend it there. Just hoping I can bend it that much
Title: Re: Yew stave straightening
Post by: Del the cat on March 16, 2023, 04:30:48 am
That'll be fine... just give it plenty of time in the steam and over bend it slightly.
Steam bends can slowly creep back sometimes (even a week later!) but if that happens, heat treating seems to fix the bend in place.
Del
Title: Re: Yew stave straightening
Post by: Muskyman on March 16, 2023, 09:52:29 am
Thank you Del. I’m going to give it a go following the video on your site. Take it down to about floor tiller. Handle area to about a inch and bend, if I remember correctly, steam it and bend about 25 percent more then the correction needed. I don’t have a steamer like yours but have a pot and some foil. About how long in the steam before bending. 1/2 a hour?
Title: Re: Yew stave straightening
Post by: Del the cat on March 16, 2023, 10:40:11 am
I'd say 1/2 hour minimum. 40 mins to be safe.
Do a dry run so you can get it jigged up or onto a form as quick as possible once it's out of the steam. Or even better arrange some sort of jig so you can steam it while it's on the jig and bend it ito position after the appropriate time... that works well 'cos you can lean on it an feel when it starts to soften up and start bending.
Del
Title: Re: Yew stave straightening
Post by: Muskyman on March 16, 2023, 09:03:01 pm
Did some work on my stave today. Got it taken down pretty good and closing in on my bow shape..
Need to thin it down some more. It’s about 1 1/4 now.. probably try to get it close to floor tiller tomorrow and get setup for some bending. It’s also got a little twist in one limb I’ll try to get out after I straighten it up..
Title: Re: Yew stave straightening
Post by: Muskyman on March 17, 2023, 03:25:13 pm
More work today and then I thought I’d test out how to straighten it before I try to straighten it. Probably try to straighten tomorrow.. probably over bend it more than my test bend..
Title: Re: Yew stave straightening
Post by: Muskyman on March 17, 2023, 04:26:03 pm
Another question.. can you take deflex out of a yew stave? This one has a little bit. More in one limb than the other. More in the outer half on both limbs if I remember correctly..
Title: Re: Yew stave straightening
Post by: superdav95 on March 17, 2023, 04:46:53 pm
Yes you can.  I’ve done this with mild deflex with no problems.  Like stated already here by others go a little past straight as some spring back does occur.  On mine with yew I rough it out pretty well then do my bend corrections in the mid section first then any limb correction from there.  You could even induce a little reflex as well. 
Title: Re: Yew stave straightening
Post by: Muskyman on March 17, 2023, 05:25:33 pm
Thanks Dave, don’t want to get to crazy with it. Most of the straightening is in the handle area. Planning on taking it down to a better bow shape after that.  Trying not to get crazy after burntstick had his bow break I’m a little nervous..
Title: Re: Yew stave straightening
Post by: superdav95 on March 17, 2023, 07:05:51 pm
Ya I find that yew is more susceptible to getting too brittle with too much heat so tread carefully.  Osage is little more resilient I find to heat corrections.  I don’t the amount of correction you need is excessive.   Good luck with it. 
Title: Re: Yew stave straightening
Post by: Muskyman on March 18, 2023, 09:01:59 pm
Steaming then clamping today
Title: Re: Yew stave straightening
Post by: Muskyman on March 18, 2023, 09:02:51 pm
Clamped .. didn’t come out perfect but got most of the bend out
Title: Re: Yew stave straightening
Post by: Muskyman on March 22, 2023, 03:29:36 pm
Any thoughts on how to handle this?
Title: Re: Yew stave straightening
Post by: Muskyman on March 22, 2023, 03:30:57 pm
Another pic
Title: Re: Yew stave straightening
Post by: Muskyman on March 22, 2023, 03:32:17 pm
One more
Title: Re: Yew stave straightening
Post by: Muskyman on March 22, 2023, 05:14:43 pm
I figure I have two options. I can pop it out and try and glue it back or try and file it out and see if the limb has enough heart wood to still hold up.  It’s closer to the fades but maybe not close enough.
Title: Re: Yew stave straightening
Post by: Hamish on March 22, 2023, 05:36:25 pm

I would bring the stave to final dimensions for width( with a little extra at the tips), then start tillering, and don't do any more heat corrections until you absolutely need to, ie get it to a 4-5" brace height, but not drawn more than 15"(less if feasible). Hopefully when you get to that point, the knot will have disappeared.

I wouldn't try and pop out the knot, its likely to tear out rough.

Title: Re: Yew stave straightening
Post by: Muskyman on March 22, 2023, 06:28:36 pm
It’s just starting to bend slightly on the floor tiller, barely flexing. Should I follow the contour of the sapwood on the belly of the bow like in the pic I posted below?
Title: Re: Yew stave straightening
Post by: Hamish on March 22, 2023, 10:19:30 pm
 Register the thickness of the limb from the back(so follow the flow of the sapwood). A pair of outside calipers will allow you to check that the limb doesn't get too thin around that curve, and create a weak spot.

Title: Re: Yew stave straightening
Post by: Muskyman on March 24, 2023, 12:49:53 pm
Took your advice Hamish. Took it down to bow shape and have it bending more but not quite ready for a long string yet but close. Working on it with the scraper. Should cut knocks in and get a low brace today or tomorrow.
Title: Re: Yew stave straightening
Post by: Muskyman on March 24, 2023, 12:50:52 pm
Pic #2
Title: Re: Yew stave straightening
Post by: Muskyman on March 24, 2023, 05:51:41 pm
Would this be to much reflex for this piece of wood?
Title: Re: Yew stave straightening
Post by: Muskyman on March 24, 2023, 05:52:22 pm
Pic of the deflex
Title: Re: Yew stave straightening
Post by: Hamish on March 24, 2023, 07:16:18 pm
Would this be to much reflex for this piece of wood?

You will end up with more reflex than I generally would want. I aim for 1-1.5" of reflex after bending. That being said you look like you will get 3-4 inches. Now some people like that amount, so it will work for them. The higher the reflex the trickier it can be to first get a string on it, without removing too much wood, and coming in under intended final draw weight. A bow stringer is good help when first getting it to brace height.
 
If you don't want as much reflex, you can still use this form. You can use 1"  or larger dowels under each tip, to limit the distance bent, and hence reduce reflex. Get ones made from a wood that isn't too hard so it won't damage the back of the bow. If you can easily dent it with a thumbnail, you should be good to go. No need to really clamp it down too hard into the form. You can  bridge the space between the tip, back towards the handle with a smaller diameter dowel, eg 1/2", if you deem it necessary, to your own eyes.
Title: Re: Yew stave straightening
Post by: Muskyman on March 24, 2023, 10:20:30 pm
I’ve got 3 or 4 small knots that seem to be rotten. Maybe 3/16 inch around. Should I pick out the rotten wood and fill with sawdust and super glue?
Title: Re: Yew stave straightening
Post by: Muskyman on March 24, 2023, 10:41:06 pm
Knots
Title: Re: Yew stave straightening
Post by: Muskyman on March 24, 2023, 10:41:44 pm
Another one
Title: Re: Yew stave straightening
Post by: Muskyman on March 24, 2023, 10:43:05 pm
Another