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Main Boards => PowWow => Topic started by: Steve Kendrot on May 14, 2008, 11:47:00 PM

Title: First BBO! Tiller help?
Post by: Steve Kendrot on May 14, 2008, 11:47:00 PM
Hello Y'all,

Admiring all the bowyery magic on this site over the last couple years has inspired me to give it a go. Here is the result of my first BBO (first bow ever really except for a maple board bow that didn't do much). Cut the osage myself with a friend and bought the Boo from Mike Westvang. Received plenty of advice from Mike and others who've tillered his bows, and read and watched everything written and recorded by Dean Torges about a million times and here I finally am...

Ready for your feedback on my final tillering efforts.

This bow is a r/d straight from Dean's video. 64" NTN and upper limb (on the right in the photo) a bit longer (1 5/8" I think). I lost some deflex in the glue up of the handle which I laminated strips of bocote and osage to build up.

As you can see, I've got the two limbs braced at a little over five inches here and the string is pretty parallel to my guidelines (which are spaced 2" apart).

(http://i33.photobucket.com/albums/d83/skendrot/IMG_0916.jpg)

Here, I've drawn to about 20" and I see that the upper (right) limb is flexing about an inch more than the lower (left) limib. I don't know if this is to be expected given the upper limb is longer, or should I weaken the lower limb to bring both tips to the same line?
(http://i33.photobucket.com/albums/d83/skendrot/IMG_0917.jpg)

What are your thoughts on tiller?

I don't have a bow scale and I am concerned about making my weight of 50 lbs. I haven't drawn it past 20" cause I'm chicken. At what point can it be drawn to 28? once the limbs are flexing evenly?

Thanks in advance for your feedback.

Steve
Title: Re: First BBO! Tiller help?
Post by: Apex Predator on May 15, 2008, 05:25:00 AM
I'm just a beginner as well, but that's looking really good to me.
Title: Re: First BBO! Tiller help?
Post by: pine nut on May 15, 2008, 07:26:00 AM
In the flexed picture the bow looks like it is not centered up on the tiller tree.  It looks as if there is more handle at the fade to the right of the tree, and also the draw rope looks off center a little to the right.  I think this could affect your perspective.  Correct that and post more pics.  I'm a beginner too, but it looks like that is affecting the bow and perhaps giving a false impression.  Anybody else see it too?
Title: Re: First BBO! Tiller help?
Post by: pine nut on May 15, 2008, 07:30:00 AM
Lay a piece of paper on the screen and mark the distance from the draw point to the knock on the left and then slide the measure to the other side and you can see the difference.
Title: Re: First BBO! Tiller help?
Post by: RayMO on May 15, 2008, 07:51:00 AM
Hi Steve,

I have made several of these BBO and likewise have tried my best to follow Deans instructions. Some of them turned out to be shooters and some not so good.

If you have not read Dean's latest article on tillering the organic bow:

 http://www.bowyersedge.com/organic.html  

I suggest that you do. He talks about the tillering tree like you are using and how it causes trouble seeing the dynamic center. I think if you would use a radius instead of two brackets to hold the bow you may see that lower limb is not so much off. My tiller tree is currently like yours also.

Regardless, you have a really nice bow there.

Are you using faceted tillering as Dean recommends?

I am gluing up another one this coming weekend.
Title: Re: First BBO! Tiller help?
Post by: Steve Kendrot on May 15, 2008, 09:23:00 AM
Thanks for the feedback. I made my tillering tree based on Dean's picture in his Hunting the Osage Bow book. The center of the bow (marked by a node in mid-handle) is lined up on the center of the tillering tree. The hook, I thought was supposed to be on the edge to simulate where the fingers would be. Maybe I've got it wrong, but his design shows a nail on the left side to route the string up the left if you flip the bow over...

I did tiller with facets, though I was unprepared for how thin and flat the limbs would get at mid-limb. I've only seen one of these bows in person (a Dryad bow blank tillered by a friend) so I really didn't know what to expect.

I also shoot 3 under. Should I do anything differently to account for that?
Title: Re: First BBO! Tiller help?
Post by: Steve Kendrot on May 15, 2008, 08:39:00 PM
ttt
Title: Re: First BBO! Tiller help?
Post by: John Scifres on May 16, 2008, 11:30:00 AM
I have grown very fond of Dean's organic bow tillering principle.  Basically, place the center of the bow on a radiused support.  Then pull the center of the string.  Tiller it perfectly like that and you will end up with a sweet shooter.  Your middle finger will initially pull on the middle of the string.  Your bow hand will focus effort on the middle of the bow.  You will tune for nock point using properly spined arrows.

Your bow looks great so far BTW.  Proceed with cautious confidence.
Title: Re: First BBO! Tiller help?
Post by: RayMO on May 16, 2008, 11:51:00 AM
John,

Any examples of what the tiller device would look like. I understand the radius and it makes sense but how do you hold the thing in place?

RayMo
Title: Re: First BBO! Tiller help?
Post by: John Scifres on May 16, 2008, 02:54:00 PM
Tillering the Organic Bow (http://bowyersedge.com/organic.html)  

 There are some pics here but the reading is better. (http://www.bowyersedge.com/ABC_06fin.html)
Title: Re: First BBO! Tiller help?
Post by: Steve Kendrot on May 16, 2008, 09:27:00 PM
Thanks! I got my scale in the mail yesterday. Appears I've made my first kids bow! 30#@28. How much can I increase the weight by shortening the limbs? I'll probably leave it, curious more than anything. I've shot some arrows out of it. Really zings an arrow for such a light bow. I am hooked now. Can't wait to start the next one though I have a bit of work left on this one.

I'm picturing a tire rim profile for the radiused bow holder. Something to nestle the bow.
Title: Re: First BBO! Tiller help?
Post by: RayMO on May 17, 2008, 08:27:00 AM
Steve,

I have shorten limbs before, hard to say. I am sure John can give a better answer...you may get 5 to 10 pounds, but IMO it messes up the bow.

John,

Thanks for that second link! That is exactly what I was looking for. Great. I am at the work bench now getting ready to mix up some Urac.

Maybe I will post a pic later just for grins..

RayMo
Title: Re: First BBO! Tiller help?
Post by: Pat B. on May 17, 2008, 09:09:00 AM
Swap ends of the bow on the tree, ie; top limb on left and see if the tiller appears the same.

Looks good !
Title: Re: First BBO! Tiller help?
Post by: RayMO on May 17, 2008, 12:01:00 PM
Just another glue up.
At this point you never know what your going to get  :D  
(http://i23.photobucket.com/albums/b365/RRZESCH/BooGlue.jpg)
Title: Re: First BBO! Tiller help?
Post by: John Scifres on May 17, 2008, 09:34:00 PM
You can gain maybe 5# cutting 1" off each side.  You might get 10# if you really hack it.  I'd start a new one or glue on some more belly wood.
Title: Re: First BBO! Tiller help?
Post by: Keefer on May 17, 2008, 09:57:00 PM
Steve, Give me a P.m and let me know if you would like to meet me at Dunkin Donuts in cambridge maybe Wed. or whatever suits you and I will loan you the dryad d.v.d ....Sorry I forgot to get that to you sooner  :banghead:  Man to think I may be the reason that bow went from 50# to 30# in just a few scrapes of the scraper.....Looks good so far and can't wait to see the results...Keefers <")))><
Title: Re: First BBO! Tiller help?
Post by: Steve Kendrot on May 18, 2008, 01:22:00 PM
I'm getting lots of votes for build another one...So I think that's my plan. I'll finish this one up as I go.