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Main Boards => PowWow => Topic started by: 30coupe on July 17, 2007, 03:00:00 PM

Title: Board too dry? Help all you bowyers.
Post by: 30coupe on July 17, 2007, 03:00:00 PM
I am working on my third unsuccessful attempt at building a board bow. I started with a hard maple board with nearly perfect grain and a nice curly figure to it. I added a hickory backing from 3Rivers, so I thought this would be the one!

Everything looked good as I began tillering the board. One limb had a slight hinge developing, but I worked that out. I was getting close. I was shooting for 45#. I was at 45# @ 12 inches and all looked pretty good. As I continued rasping/scraping then exercising the bow one limb suddenly started to show string follow. When I got it back to the vise, it looked like there were numerous small cracks developing. I went a bit further and the cracks increased. It looks like they are developing in line with the curly figure in the grain.

It looks like another learning experience instead of a bow...again. What do you think all you bowyers? Is it the structure of the maple or was the board too dry? There were no cracking noises, I followed the work a little-excercise a lot routine, but there is no way this is going to make a bow.

Help!  :banghead:
Title: Re: Board too dry? Help all you bowyers.
Post by: Chris Lantz on July 17, 2007, 03:27:00 PM
Curly figure in the grain? Is your maple board highly figured? That could cause you problems. That's just a guess, I'll let some of the more experienced guys weigh in.

Don't get discouraged, take everything you learned from this experience and apply it to your next bow. You'll get al the kinks worked out and have a sweet shooting bow soon enough.
Title: Re: Board too dry? Help all you bowyers.
Post by: Pat B on July 17, 2007, 04:20:00 PM
If the cracks are in the belly, they are probably frets...compression fractures. They either happened when you hinged the limb or the wood was weak, for some reason, and that caused the frets. How thick is your hickory backing? that could have possibly overpowered the belly also. With wood like maple, lighter backing wood might be the ticket. Wood like elm or even more maple.    Pat
Title: Re: Board too dry? Help all you bowyers.
Post by: 1/2primitive on July 17, 2007, 04:45:00 PM
Like Pat said, it might help to use a lighter backing. You could even go with a heavy linen fabric.
   Sean
Title: Re: Board too dry? Help all you bowyers.
Post by: 1/2primitive on July 17, 2007, 04:46:00 PM
And these cracks are on the belly, right?
   Sean
Title: Re: Board too dry? Help all you bowyers.
Post by: 30coupe on July 17, 2007, 06:08:00 PM
Yup, the cracks are on the belly. The backing is 3/16 hickory. I think that may be the problem. The hinge was not enough to cause it and the cracks are not limited to that area.

I just keep on learning. Someday I'd like to end up with a bow! I thought the hickory backing would be just the ticket. Oh, well...  :knothead:
Title: Re: Board too dry? Help all you bowyers.
Post by: Keith Deters on July 17, 2007, 06:21:00 PM
Curly maple is not a good belly wood.  Maple without the curl works well, depending on the backing and your tillering ect... ect..
Title: Re: Board too dry? Help all you bowyers.
Post by: Pat B on July 17, 2007, 11:20:00 PM
You want straight grain wood for board bows and grain that doesn't(or with little) run off the top, bottom or the sides. Check out Jawge's site for info about board bows. Mickey's site too.
  The 3/16" hickory backing is too thick in my opinion. 1/8" or even less is good.
  As far as the frets. I have made bows that fretted all along the limbs belly. Sometime you get a piece of wood that is just too weak in compression for bows...even osage.  Fretting can also tell you where your limb thickness has decreased(very slight hinge) without your knowledge. Study your limb thickness closely and you can probably see what you did wrong. I know this from experience...like most wood bow builders.    Pat
Title: Re: Board too dry? Help all you bowyers.
Post by: 30coupe on July 17, 2007, 11:31:00 PM
I think I'll try something other than maple. This is the second one that didn't work out. I did a red oak board bow that worked for a while, but the bottom limb cracked. I lightened the draw and wrapped the crack with sinew. It still shoots, but only draws about 35 pounds. Another crack is developing, so I think it is retired.

I just haven't found another straight grained board yet. I wonder if the ones at Menards are just too dry to make good bows.
Title: Re: Board too dry? Help all you bowyers.
Post by: George Tsoukalas on July 18, 2007, 08:13:00 AM
Have you tried red oak or hickory. Look for straight grained stock. More info on my site in the "How to" section. Jawge
Title: Re: Board too dry? Help all you bowyers.
Post by: 30coupe on July 18, 2007, 04:59:00 PM
Jawge,

I did try red oak. That one cracked in the lower limb. Otherwise it was better than the maple.

Russ
Title: Re: Board too dry? Help all you bowyers.
Post by: Jeff Strubberg on July 18, 2007, 05:43:00 PM
Curly means by definition it won't build a board bow.

Good grain for a board bow is the opposite of "good-looking" grain.  You want NO curl, NO wiggle, nothing but nice, boring, straight lines.