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Main Boards => The Bowyer's Bench => Topic started by: critman on March 12, 2013, 10:16:00 PM

Title: about ready to throw in the towel
Post by: critman on March 12, 2013, 10:16:00 PM
Thursday is my neice's birthday. She will be 10, but is small for her age. I told her I would build her a bow for her birthday. I decided to make a TD bow for her. It would come in at around 15-17# @ 24" draw. Riser turned out great, limbs looked good. Problem is that the upper limb is stronger than the lower. It has about 1/4" more tiller than the bottom. This is a LOW poundage bow so the limbs (which are solid wood) are about 1/4" thick. I have scraped and scraped and scraped but don't see the tiller changing much. Do I keep on scraping or possibly just make a new limb? Both limbs bend quite easy as the bow is 55" long. I don't think it will be ready for her birthday if I make a new limb. Oh well.........  :banghead:
Title: Re: about ready to throw in the towel
Post by: Millhimes on March 12, 2013, 10:28:00 PM
Critman,you mean the top limb measures 1/4 " less than the bottom limb? On this low poundage i don't think it will hurt anything.If you are concererned,just let her shoot it as is while you make a new one
Title: Re: about ready to throw in the towel
Post by: fujimo on March 12, 2013, 10:40:00 PM
maybe take a little off the sides- go at that REAL slow an careful. a little goes a long way.flex it well between wood removals
Title: Re: about ready to throw in the towel
Post by: critman on March 12, 2013, 10:48:00 PM
Millhimes, have I got this tiller thing backwards? The string is closer to the bottom limb than the top limb as measured from the top of the riser when drawn to about 20 inches.  I can defintely tell the bottom limb is bending more on the tiller tree. I guess I am being paraniod about tiller. I am unfortunately a stickler for details, to a fault. Of course it's my own fault! I think I'll finish this one up, give it to her and make her another, better bow. I do have 3 more glued up. Love to see the look in a kids eyes!
critman
Title: Re: about ready to throw in the towel
Post by: Steve Kendrot on March 12, 2013, 11:16:00 PM
Are you measuring your tiller measurements  with the bow at brace? Your post above reads as if you are measuring tiller when the bow is drawn and I don't believe that is how it's done. A lower tiller on one limb indicates that limb is stiffer than the other (it's not bending as much). So if you are removing wood from the limb with the higher tiller measurement, you'd be making it worse I think.  At any rate, a 1/4" doesn't sound like a big problem, especially for a light bow. Post some pics?
Title: Re: about ready to throw in the towel
Post by: MoeM on March 13, 2013, 05:43:00 AM
Impossible to turn her round to get proper tillerunequality?
Title: Re: about ready to throw in the towel
Post by: critman on March 13, 2013, 09:03:00 AM
Steve, I have measured at brace and drawn. Numbers are the same so the top limb is a little stiffer and that is the limb I have been working on. It's really not that big a deal after I have re-read my post and the others. I haven't even shot the bow yet so I probably have just gotten ahead of myself as usual. Thanks for the input.

MoeM- I wish I was good enough to say that both limbs matched the riser perfectly but my drill bit wobbled so no way to reverse limbs. Poor building form on my part.

Still learning and learning alot with yall's help.
critman
Title: Re: about ready to throw in the towel
Post by: MoeM on March 13, 2013, 09:12:00 AM
What kind of bow are we talking about exactly? Seems to be a three part TD recurve right? If it`s glasslaminated you coult do some trapping on the strongers back.
Title: Re: about ready to throw in the towel
Post by: BenBow on March 13, 2013, 09:32:00 AM
Well if you top limb is stiffer just shorten the bottom limb a 1/4 to a 1/2" and you'll be fine. Just move your nock closer to the riser on the bottom limb. You can do a 1/4" at a time and see what works.
Title: Re: about ready to throw in the towel
Post by: macbow on March 13, 2013, 03:53:00 PM
Also it would be,good,to get some arrows shot through it. The tiller may change after that.
I had a BBI longbow make a change after 200 shots.
Title: Re: about ready to throw in the towel
Post by: Millhimes on March 13, 2013, 04:13:00 PM
Critman,with the bow at brace,measure at the end of the limb wedges.The lower number is the stiffer limb.If the lower limb is say 6 1/2 and the top limb is say 6 3/4,that is 1/4 positive tiller.When i put them on the tree to check the tiller,i level the string with my lines to see if it holds the same at full draw.
Title: Re: about ready to throw in the towel
Post by: critman on March 13, 2013, 06:30:00 PM
Thanks again guys for all the help. The top limb was definitely stiffer and now I know why. Even though I measured and re-measured after I glued up the tip overlays (just to make it look better) I must have gone crazy with the file. The upper limb was 1/2" shorter than the bottom. Not to be undone cut new limb and have overlay glueing up right now. I will not give up! I would love to post pics of all my misadventures but still haven't figured out how to use photobucket. Pitiful for a man that uses a computer all day long. I'll figure it out soon.  Maybe?  :knothead:
Title: Re: about ready to throw in the towel
Post by: 7 Lakes on March 13, 2013, 07:53:00 PM
If you take off wood the tiller will change.  Draw the bow 15 to 20 times between removal work.