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Main Boards => The Bowyer's Bench => Topic started by: Weedle on June 23, 2014, 05:16:00 PM

Title: Tillering 4est Style Pyramid Bow
Post by: Weedle on June 23, 2014, 05:16:00 PM
Hello all, I've been lurking on this site as well as all the other excellent traditional archery sites and blogs for a while now, and have built my own red oak pyramid bow up to the tillering stage.  It is 68" from tip to tip, paper bag backed, and I am planning on using poplar for tip overlays and final handle ergonomics if it gets past the bendy stage    :rolleyes: . I've made my own tillering tree/flemish twist jig as you can see in the pics, have the bow strung up with a long string and have just begun pulling and testing weight, VERY tentatively.  I will need input throughout the tillering stage, but here is my question for right now:
The bow is very heavy at the moment and is pulling 30# @ 10.5".  Hardly any bend is required to get it that far; the string sits at the 5" mark at rest.  What kind of weight should I be pulling at various distances with the long string?  I know most people don't worry about weight with long string, they floor tiller to get it much closer than I am and use the long string and eyeball it for general bend, until they can get a low brace.  But that comes with experience, which I do not yet have.  I've been referencing George's site, Poorfolk Bows, and of course Vol. 1 of TBB, but I'd like some general feedback (numbers!) on this before I go ahead and screw up my first effort.  Once I get a feel for what a properly tillered bow pulls at various stages, I will be able to read it by feel and not worry so much about stats.  I've been going VERY slowly on this first one to learn as much as possible, and it would be awesome if I could end it in success. Shooting for #45-50 @ 27".  Thank you all!    (http://i652.photobucket.com/albums/uu247/slagatronprime/Mobile%20Uploads/20140617_000212.jpg)    (http://i652.photobucket.com/albums/uu247/slagatronprime/Mobile%20Uploads/20140623_164602.jpg)  (//%5Burl=http://s652.photobucket.com/user/slagatronprime/media/Mobile%20Uploads/20140615_230622.jpg.html%5D%20%5Bimg%5Dhttp://i652.photobucket.com/albums/uu247/slagatronprime/Mobile%20Uploads/20140615_230622.jpg)[/url] [/IMG]   (http://i652.photobucket.com/albums/uu247/slagatronprime/Mobile%20Uploads/20140614_170408.jpg)   (http://i652.photobucket.com/albums/uu247/slagatronprime/Mobile%20Uploads/20140616_173846.jpg)
Title: Re: Tillering 4est Style Pyramid Bow
Post by: Echatham on June 23, 2014, 06:55:00 PM
hey i like that dual purpose jig and tree thang.  nice.  i would just go with the long string until the limbs are bending about what they would at a normal brace height, then brace it low.  i skip all that now and go straight from floor tiller to a 3 or 4" brace, and then tweak the tiller until it looks good braced.  then... i start pulling on it.  on a bow thats supposed to end up 45#  i get them to about 55-60 # by first brace.. just by feel... then shed 5# tweaking the braced profile.
Title: Re: Tillering 4est Style Pyramid Bow
Post by: Sam Harper on June 23, 2014, 07:03:00 PM
If you're shooting for 45#, just pull it until your bow scale reads 45#, and see how far that is.  If the limbs are traveling at least 10" when you pull it to 45#, go ahead and string it.

After that, just pull it to 45#, and tiller from there.  Never pull it more than 45#.  Keep removing wood from the belly, checking to make sure the tiller is even, until it's 45# at 27".  Then you're done.  After you sand it and shoot it a bit, it should settle in at 45# at 28".
Title: Re: Tillering 4est Style Pyramid Bow
Post by: Weedle on June 23, 2014, 08:40:00 PM
Awesome, thanks for the quick replies. I'll be nabbing a cabinet scraper tomorrow to use, and also hunting for some more goose primaries and secondaries for my fletching. Will update as I go, I'm sure I will want some opinions on the tiller profile as it progresses. Oh, and Sam - your blog is fantastic work. Your methods for Flemish twisting worked perfect for me, and I love the humor built into your how-to's Good luck with those cats.
Title: Re: Tillering 4est Style Pyramid Bow
Post by: Weedle on June 24, 2014, 03:32:00 AM
So this is what I get @ 45#. When people say "10" movement" do they mean tip deflection, or the string from its point of contact with the tiller pull rope? Also, am I correct in thinking this tiller (obviously very heavy) needs the mid limbs lightened a lot? The entirety of both limbs needs to be thinned, but Im also getting no mid limb bend. Do I evenly remove wood across both limbs and THEN adjust for mid limb stiffness, or do i remove equal amounts from just the mod limbs of each arm? With this much extra wood I suppose I could really do either.
  (http://i652.photobucket.com/albums/uu247/slagatronprime/Mobile%20Uploads/20140623_214248.jpg)
Title: Re: Tillering 4est Style Pyramid Bow
Post by: Sam Harper on June 24, 2014, 09:12:00 AM
I meant the string should move 10".

It may be an optical illusion because of your handle being narrow, but it looks like most of your bend is happening right at the ends of the fades.  So I'd remove wood evenly along both limbs from a couple of inches past the fades to the ends.  Just count the strokes and do the same number of strokes on one limb as you do on the other and check again.