Primitive Archer

Main Discussion Area => Bows => Topic started by: Tree_Ninja on November 29, 2015, 02:08:36 pm

Title: Crysal fix
Post by: Tree_Ninja on November 29, 2015, 02:08:36 pm
 
Hello folks,

This one was a bit of a fail. I must not of shot it in enough after tillering (before finishing) and missed a bad tiller. A couple of crysals showed up between a couple of stiff spots.

Its oceanspray 66" NTN. Was 44#@28".  As you can see I had put a leather wrap and handle and finished with poly (which is how I found the crysals)

Ive removed wood on the stiff section and between crysals. The left lim is lower, and sitting  a little higher on the tree because of the handle. (Bend thru). Its about 25" draw now.
The tips seem stiff still. I found one crysal about 6" on the bottom limb and another about 10" on the bottom limb (from center)

All tips and comments appreciated.
Title: Re: Crysal fix
Post by: Tree_Ninja on November 29, 2015, 02:15:46 pm
Crysals on bottom limb
Title: Re: Crysal fix
Post by: PatM on November 29, 2015, 02:32:01 pm
Looks like OS doesn't like pins. Many really hard woods are like that. Nothing you can do except start over and try leaving areas with pins a bit wider.
Title: Re: Crysal fix
Post by: bow101 on November 29, 2015, 02:34:39 pm
I see your dilemma Ninja.   Try to challenge yourself like DC build bows with a non bendy handle.   Believe me; you will get to the punch much quicker,   your tillering expertise will develop faster.   
Never the less your work is looking better.  :)
Title: Re: Crysal fix
Post by: bradsmith2010 on November 29, 2015, 02:34:52 pm
well it does not seem the bow was not bending evenly,, it still looks to need work,, getting the stiff parts to do their share of the work
fixing a crysal,, is very debatable,,yes it can be done, I have seen the whole belly scraped flat and wood or horn laminated on,and  thats alot of work,, you will get alot of opinions on the state of your bow,, and it is really hard to tell from the pic,,
I have a black locust bow that fretted or got a crysal,, I evened up the bow and it is shooting 20 years later( after many tournaments and a nice buck to boot), so it can depend on how severe the damage is,, if it was my bow,,  I would even it up the best I could to a lower weight and just see how it goes,, if the damage is light ,,,it may hold up,, or it may get worse and then you would have a wall hanger,, :)
Title: Re: Crysal fix
Post by: wizardgoat on November 29, 2015, 03:11:41 pm
Your limbs are not bending much, especially the right.
PatM is right, OS does not like pins, problem is its next to impossible to find a clean stave.
I made an OS bow a while back that had frets around pins very early on, and they still made bows.
Mine were a little raised, you could really feel them
Title: Re: Crysal fix
Post by: wizardgoat on November 29, 2015, 03:15:21 pm
http://www.primitivearcher.com/smf/index.php?topic=52209.0

This bow has shot many hundreds of arrows, but has been hung up for the past while.
Title: Re: Crysal fix
Post by: Del the cat on November 29, 2015, 03:16:05 pm
Chrysals go surprisingly deep.
You can rasp out a gentle scoop going about 3/16-1/4" deep and glue in a matched patch. BUT you must ease off those outers to get e'm moving else you'll just get the same again.
Treat it as a no loose experiment.
Del
Title: Re: Crysal fix
Post by: bradsmith2010 on November 29, 2015, 03:34:42 pm
I have never worked with OS,, but if you could make it a bit longer next time,, it would give you more wood working,, or if the stave wont allow,,,, make the draw shorter,, :)
Title: Re: Crysal fix
Post by: Tree_Ninja on November 29, 2015, 03:45:18 pm
Thanks guys. I know fixing crysals doesn't really work, I was more looking for the cause. I'll remove some wood from the outer limbs to get it working more.

  I have a couple other bows with worse crysals than this I have kept shooting, I was just hoping this one turned out. Oh well, Next one.

Title: Re: Crysal fix
Post by: bradsmith2010 on November 29, 2015, 03:50:11 pm
the main cause it the wood needs to work more evenly,, and that just takes practice,, you are on the right track,,
Title: Re: Crysal fix
Post by: Del the cat on November 29, 2015, 04:16:35 pm
... I know fixing crysals doesn't really work...
grrrrr. It does work if you rasp 'em out, patch and re-tiller >:(
Del ;)
Title: Re: Crysal fix
Post by: Tree_Ninja on November 29, 2015, 04:51:37 pm
Quote
grrrrr. It does work if you rasp 'em out, patch and re-tiller

I meant it probably won't work for me. I am hoping to fix this, so I might get a bit creative.
Title: Re: Crysal fix
Post by: DC on November 29, 2015, 05:13:07 pm
Bring it up when you drop in. I hate to say this but The only Os bow I made that crysaled  was my very first and it was about 5' long and I was pulling way back close to my 27" draw. I got major crysals. Since then with decent lengths I've had no problems(touch wood). 66" should be lots. especially with a bendy handle. The only thing I can think that I do is flood any small knots or pins with thin CA and then I keep doing it as I work my way down. Bit that doesn't seem like a major thing. I have a little bow that I patched some thin spots(like Del mentioned) and it was easy and lasted.
Title: Re: Crysal fix
Post by: bradsmith2010 on November 30, 2015, 11:38:43 am
I was just reading Jay Massey,, he suggest drilling out the pins and replacing with wood plug to prevent cracking around the knot,,,, I have never tried this .. osage doesnt seem to mind pins,, but I think if it worked for Jay,, it could work for the OS,,
Title: Re: Crysal fix
Post by: LittleBen on November 30, 2015, 11:53:16 am
Tiller is the cause of your problem as much as the pin knot.

My very general recommendation when tillering is this. Don't ever draw the bow more than necessary to see where to scrape.

Until those outer 2/3 of both limbs are working you're gonna get fretting.

You could try to repair them, but I would tiller it out better first.
Title: Re: Crysal fix
Post by: crooketarrow on November 30, 2015, 12:16:28 pm
   This is a easy fix.

SLOW DOWN WHEN THE TILLERING STARTS.

 I was self taught for 10 years before I met CROOKETARROW.

  Heres what he ment by saying SLOW DOWN.

  Naturally just slow down look at your bow from all side as you tiller. There's no hurry.

  But mainly after you do your tillering a little at a time. Leaveing it over night then next morning each time.

  Your fresh you can see where you need to retiller places from last night.

  DO THIS YOU'LL NEVER HAVE TO WORRY ABOUT CRYSALS

 Good tillering means no crysals.
Title: Re: Crysal fix
Post by: Tree_Ninja on November 30, 2015, 12:33:37 pm
I've had this one sitting in the shame corner for 4-5 months now as a specific reminder to go slow (and to ask on here).

I was using a photo  app to draw a curve on the bow and it looked good (to me) every inch to full draw. I think that step misled me a bit. There also might of been a bit too much moisture  in it. After tempering I had to re tiller again, and It might not have equalized with moisture. Anyhow, I definitely don't want to make those mistakes again.

I have since moved on to other projects (with success), and I am going super slow with my tiller.
Title: Re: Crysal fix
Post by: bradsmith2010 on November 30, 2015, 12:58:16 pm
I think the reason a photo app,, may not work all the time,, is the stave can have some reflex and deflex that needs to work evenly,, the taper when kept perfect, may not fit a pre fab line,, every bow is slightly different on a stave bow,,
Title: Re: Crysal fix
Post by: randman on December 03, 2015, 09:37:17 pm
I don't think crysals on OS are as big an issue as they are on other types of wood and one thing I do know is you don't have to worry about OS "exploding". I've used lots of OS and broken lots intentionally and none "exploded". The grain is so interlocked that it just kind of shreds and bends when it goes. Takes a lot of work to get it to break.
Title: Re: Crysal fix
Post by: George Tsoukalas on December 04, 2015, 04:31:11 pm
My take....
That first photo suggests that stave is about to fold in on itself like closing a book. The second one confirms it.
I had that happen on the first bow I tried to make for my brother...Lord rest him.
It happens.
Time to start another.
Jawge