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Main Boards => The Bowyer's Bench => Topic started by: razorback on August 18, 2015, 08:27:00 AM

Title: Chrystle repair ideas
Post by: razorback on August 18, 2015, 08:27:00 AM
So I have a hbh pyramid bow that I love the look and feel of. Unfortunately it developed compression fractures I tried Dean's patch on one bat h but then found more, so I put it aside. Was supposed to be a swap bow from a couple of years ago. Anyway I have been thinking if I reduce the weight and get the tiller better and then add a belly lam of 3/16 Osage, would that secure the bow. If the current fractures are moved to the neutral plane will most of the danger from them be removed. I know that all wood bows will break and this one will probably break at one of these points, but hoping this fix might give it a normal lifespan. What do you all think?
Title: Re: Chrystle repair ideas
Post by: John Scifres on August 18, 2015, 09:43:00 AM
Details on design?  Why did it develop chrysals?
Title: Re: Chrystle repair ideas
Post by: LittleBen on August 18, 2015, 09:56:00 AM
If you add a belly lam, whatever frets were there before are nearly irrelevant. I assume we're not talking about some horrible nasty fret causing a severe hinge or anything.
Title: Re: Chrystle repair ideas
Post by: razorback on August 18, 2015, 12:37:00 PM
John, it is a Hickory backed Hickory pyramid style bow 66"ttt 2' at fades tapering to tips that are 3/8". Fretts are small and on one edge. I think the side to side thickness is off a little in those spots thus causing the stress. I just checked the osage slat and it is less than 2" wide so i may change the profile to parallel for half the length and then go with the taper to the tips.
Title: Re: Chrystle repair ideas
Post by: mikkekeswick on August 18, 2015, 02:33:00 PM
Osage would only need to be 1 1/2 wide at the fades so you would have room to play.
That edge was too thin so make sure you get it even before gluing on a belly lam.
Title: Re: Chrystle repair ideas
Post by: razorback on August 18, 2015, 02:39:00 PM
That is what I'm thinking. I will measure those areas carefully and get it even and flat before glueing on the belly.
I hate to change the taper profile a s I really like the lines of this bow, but to get a good safe working bow I may have to do it.
Title: Re: Chrystle repair ideas
Post by: George Tsoukalas on August 19, 2015, 09:19:00 AM
Retiller. Mark a big x on the chrysals and leave that area alone because it is already bending too much.

Tiller the other limb to match.

I used to slap on a piece of rawhide over the chrysals but these days I just make another bow.

Jawge
Title: Re: Chrystle repair ideas
Post by: John Scifres on August 20, 2015, 01:27:00 PM
That will work.  But you need to do a cost-benefit analysis  :)

If it were me, I'd probably just build another bow that matched the look and feel.

But I have been known to throw good money after bad and sometimes it's just fun to try something new.
Title: Re: Chrystle repair ideas
Post by: takefive on August 20, 2015, 04:39:00 PM
I'm in the same boat with a red elm board bow I made a while back.  No chrysals, but it took more set than I liked and turned out mediocre all around.  Tried some heat treating but wound up with small belly cracks on one limb trying to flip the tips.  I probably could have made a new one in less time than it has taken me to rasp and sand this one down to fit an Osage belly lam and glue it up.  Oh well.
I had backed it with cherry bark and liked the way it looked so much that I couldn't bring myself to toss it.  I'm going to start tillering it today.
Good luck with yours!
Title: Re: Chrystle repair ideas
Post by: canopyboy on August 20, 2015, 09:53:00 PM
John makes a good point if you just want the bow working again. But you learn a lot trying to fix these things I think. I've done an osage belly lam to fix frets before. The bow came out quite a shooter and I learned a lot in the process. Would I do it again if the goal was just to complete a bow? Nope. I'd just make another campfire poker out of it and start over. But I'm glad I did it the first couple of times!
Title: Re: Chrystle repair ideas
Post by: Roy from Pa on August 21, 2015, 07:03:00 AM
Once a wooden bow develops a problem on me, I turn on the band saw and cut it into fire wood. I'm not going to spend time patching up a bow which I could never trust again..