Hairline Cracks on Maple Belly

[Prarie Bowyer]

Hi all.

I'm new to bow making and have completed my first bow.  I made some classic mistakes with it but on whole it's a success.
http://www.facebook.com/#!/profile.php?id=100000955187713&sk=photos

It's hickory backed bamboo and maple.  I got this brilliant idea after it was tillered and had some string follow to clamp it in a reflexed position overnight to let it take some set like that and get some string follow out.  Later when I realized I wasn't at full brace I braced it and drew it.  The backing split in 1/2, 1/2 across the back of the bow and split vertically for about 2".  I took it off and glued on another one.  I had a mild hinge and a pinhole knot in the backing right where it broke.  I re-tillered it and dropped the weight a bit because I also got these tiny little cracks in the belly.  I have soaked them in super glue but I don't think that will be sufficient.

the bow is about 35# at 28" (down from 58).  I put so much work into it I'd prefer not to loose it to those belly cracks.  I'm looking for attractive fixes.  I consider (1) Cutting them wider then filling the slot with crushed turquoise and impact strength super glue.  (2) Wrapping the the limb at that point with something like silk or nylon thread thread for 1-3 layers then coating over with epoxy.

I think it's a bit late to add another backing because I have the tip laminations on and a riser lamination.

I love the look of maple but it seems like it forms these cracks and bumps in the belly easily while tillering.  The cracks started before the clamping idea.  I'd shave them out and they would come back.  Perhaps Maple is a poor choice for belly or limb wood or it should be sandwiched between other things?

Thanks,
PB

[El Destructo]

The Cracks that you are fighting are more than likely Chrysal's...micro-cracks caused by over-stressing parts of the Limb while Tillering...Maple is not necessarily prone to this...you just have to make sure that you never over-stress the wood while scraping and tillering...Ash is also the same...and Locust too...There rally is no Fix for Chrysal's...filling them with Super Glue...or cutting out wood and patching them...are all just Bandaid's...all I can say is to watch them...and Shoot the Bow...and get what you can out of Her....if the Bow on your Facebook account is the Bow....It's a Sweetheart...

[Prarie Bowyer]

Yea.  It's my first bow ever.  The only powertool I own is a drill and a band saw (14"JET with riser extension). . .  and a chain saw.  I'm kinda a primitive/traditional wood worker.  I HATE sanding.  I'm an avid carver and turner as well.  I learned this trick to get a great finish on detailed work with out sanding that works like a dream on Maple.  I discuss it under the "sculptures section" on a progress photo of "Benedict".  I pretty  much use hand tools as much as I can.

Thanks for the compliment.  I want to get a few more under my belt then I'll start doing gold leaf and semiprecious stone inlays.

[dmc]

Hi Prairie Bowyer, bummer about the chrysals. I've had two on my maple bow as well. Fortunately, they are on my bottom limb. Might not be the smartest idea on my part, but I love shooting it so much that I'll shoot it until it blows. I crazy glued it, and wrapped it with dacron soaked in crazy glue, and it seems to be holding.  The bow is about 45 pounds, so there isn't too much stress. (I hope) From talking with other bowyers, they all told me it was chrysals, although my head kept trying to tell me it was the finish. I'll have to go slower on my tillering for my net one. Good luck with yours. dmc

[aznboi3644]

just because its 45 lbs doesn't mean its not stressed....if its chrysaled than its stressed

[Pappy]

About all you can do is take a little before and a little after the frets,scraping them out without do that will only make it worse,it is bending to much now  in to small of an area is the problem. Sometimes they will shoot for a good while,but sooner or later they will cave and that will be the end of that.  Wished I could see it ,but I don't do face book.
   Pappy

[dmc]

just because its 45 lbs doesn't mean its not stressed....if its chrysaled than its stressed

     
I agree.......stressed is stressed. I guess I meant I'd rather have a lower poundage blow than a higher one. I know eventually it will go, but I'm having too much fun with it right now. This probably won't be my first to blow. Learn from my mistakes and carry on. Deer season is coming!!

[Prarie Bowyer]

maybe tomorrow I'll load them properly in PhotoBucket.  I'm really proud of that first bow.  I hate to loose it. I looks like it's bending evenly now but either the damage was done or it's a grain issue.  I consider avoiding maple for a while.  The local place has Birch which is straighter grained and feels a bit harder.  Maple is kinda like Pear to work, sort of waxy if that makes sense.

[Prarie Bowyer]

How do you think I caused them?  The backward bending or tillering too fast?  I did nearly all removal after bandsawing the profiles with a card scraper because I didn't want to shoot past my target weight.  I flexed the bow in progressive depths 30 times after each wood removal session. They would form and little ridges along the belly.  I'd plane/scrape them out and smooth and they would come back.

[aznboi3644]

got a maple self board bow in the corner myself with chrysals...planning on just planing the belly down and turning it into a backing strip.

[Prarie Bowyer]

Just bought a bundle of bamboo.  I think I'll be avoiding maple in the future beyond decorative laminations.  Future bows will be largely bamboo, Hickory, Ipe, or Osage, possibly birch.  I'm amazed at how long these take and the effort that goes into them.  It completely justifies the prices I see in catalogues.  With that in mind I'm not wasting time and money on bows that don't have the best chance possible of long usefull life.  I may even start using fiberglass.  I'm a sucker for Hill type bow.  A Bear Montana experience got me started in all this.

[George Tsoukalas]

I don't see any bows on that link, PB. It is no a good idea to bend a tillered bow backwards. It wouldn't take out the set anyway. I don't know if those cracks were chrysals because I couldn't find the bows. Jawge

[El Destructo]

Jawge...you had to go to His Photo's om His Facebook Page....but still there were no pictures of the cracks...needs to post some on here for us to see.....

[Hillbilly]

Just bought a bundle of bamboo.  I think I'll be avoiding maple in the future beyond decorative laminations.  Future bows will be largely bamboo, Hickory, Ipe, or Osage, possibly birch.  I'm amazed at how long these take and the effort that goes into them.  It completely justifies the prices I see in catalogues.  With that in mind I'm not wasting time and money on bows that don't have the best chance possible of long usefull life.  I may even start using fiberglass.  I'm a sucker for Hill type bow.  A Bear Montana experience got me started in all this.

It's not using maple that causes chrysals-it's having too much bending in one spot on the limb or under-designing the bow that usually causes them. I've seen chrysals in all kinds of wood, even osage. From your description, they probably popped up in the hinged area. Maple is good bow wood, seen plenty of great bows made from it. If you got a shooting bow that's in one piece on your first attempt, you did good-better than most of us did. Bowmaking is a learning curve. After doing this for over ten years, I'm still learning. It would help if you would post your photos on here instead of Facebook, believe it or not, there are a lot of people who don't do facebook.

[Prarie Bowyer]

Yea, I hardly do Face Book that much anymore myself.  I was hoping that they would make a nice photo hosting site and kill two birds with one stone.  Looks like that wasn't the case.  You must need a facebook account to get to the photos.  I also do a considerable amount of carving and wood turning which I sell so I left the link general in case there was interest in other things.

I have international guests right now while I'm in the midst of a job search so my time is mostly broken up.  I'll try to get some shots up.

So they began developing while tillering.  I'd scrape them out and remove wood around them they would come back.  The hinge seemed only very slight to me.  I exercised the limbs 30 times after all wood removal and used a scraper for 80% of the removal because I didn't want to miss my target weight, which i did anyway.  So I don't think it was because I was too aggressive with the tillering. 

I have my tillering stick screwed to my garage workbench.  I was using a roller/pulley but it was terribly out of round and caused relay rough pulling.  Maybe something with the lighting or visual there prevent me from seeing how bad the hinge was.