Tiller help...my son's bow - NOW BACKING HELP

[Monkey Wrench]

Hey guys, I'm making my 8 year old a new bow (Birthday present - Oct 21).  The one I made him 2 years ago is getting way to small, and does not shoot consistenly for him (due to the poor quality of the build...hey...it was only my second bow!)

Anyway, I've learned quite a few lessons along the way, and now I would like to make him a much better bow.  I've glued up a HBH profile, with a 1/16" strip of Ipe in there for some contrast.  

The stats...54" long, 3/8" at the tips (maybe a shade less) and 1" at the handle.  It has about 1" of deflex and 2" of reflex. Intended target weight is about 15-20 lbs, not sure of draw length yet, I need to measure his draw in a sneaky way, or he'll know he's getting a new bow.


I've never tillered a r/d profile before, only straight profiled board bows.  This is what it looks like after glue-up.

   

The photo makes is looked a bit hinges in the reflex on the left limb, must have been the angle of the shot because it's a very smooth transition.


And here she is pulled to about 20lbs on the tiller tree...

   

How do I tiller this sucker?  From first glance is looks like I need to remove material from where the delfex radiuses into reflex.  But if I do that, I would think it will develop a hinge relatively quickly.

Thoughts???

[PEARL DRUMS]

Get the mid limb area moving.

[Art B]

I would get to normal brace height with a regular string before I would go any further. Here's why: your long string is overstressing the inner limbs giving you a false look at present. When you put a short string on, the greater stress is no longer on the inner limb but now transferred to the outer portion of your limbs because of string angle. Start with an even brace AND then begin tillering your bow.

Deflexed out of the handle does require a rounded handle/inner limb profile tillered out close to mid-limb. With a straight limb profile from mid-limb to tip. Some of my thoughts, so that's how I would approach things, good luck........Art

[KellyG]

Monkey,
Can't help out with anything but the sneaky measuring bit. I would take him outside to shoot with you, and have him draw. You make it telling him you want to see if he is drawing the same every time. Then later you can measure it at your leasure. Or you could make a few new arrow with marks at know measurements and see where he draws them. Just a couple of Ideals.
Kelly

[Monkey Wrench]

Deflexed out of the handle does require a rounded handle/inner limb profile tillered out close to mid-limb.  [/QB][/QUOTE]

Ugh-oh, maybe a little late for that.  Always learning...

I'll need to remove some material before I can get it to brace height to actually tiller.  Where would you suggest I remove the material, or should I just do it evenly across the bow.  Right now it's just too stiff to get to brace w/o breaking.

[Art B]

Sounds like you're still plenty heavy enough to work in the profile you want.

First thing I would do is shorten up that long tillering string to where it'll just fit from nock to nock. I would start by removing wood inner limbs. Like I said previously, profile is going to shift when you go to a regular string and this will leave you perhaps needing some work mid-limb. Last thing you would want is to find out that you over tillered mid-limb before ever getting a short string on......Art

[Monkey Wrench]

Preach on Art, that's exactly what I was afraid of.  I'll make a shorter string tonight and try again.  Thanks for the help!!!

[Monkey Wrench]

OK, got a much shorter string, just long enough to go over the profile.  Here it is pulled to 25 lbs, about 5 inches of "brace".  Almost ready to put the short string on it.  2 questions...

1) Thoughts on tiller?  Looks to me like more in the middle third still.

2) What do you think a brace height should be for a kids bow, 6"?

 

[Chris P. Bacon]

left side looks a tad strong to me.

[KellyG]

Monkey measure your sons fist melee and set the brace at that to start. I think that should work.

[Monkey Wrench]

fist melee?  You got me on that one Kelly.  I even looked it up and couldn't find any results but unorganized combat in the middle ages.  Now...he does have a football game today at 1.  So...if you've ever watched 8 year old football...a melee is actually not a bad word to describe it!

[KellyG]

Heck I may have used the wrong word I do that sometime, have him make a fist and stick out his thumb. From the belly to the string would be the brace.  Hence if you measure it you would have an ideal where to start. I thought it was called fist melee but I can't remember it’s something like that.

[Stiks-n-Strings]

A fistmele is the traditional means of measuring an archers brace height.

 You make a fist and stick out your thumb like your trying to hitch a ride. The distance from the tip of your thumb to the back edge of your hand is your fistmele
 
 Stiks

[KellyG]

I just add one to many e's

Thanks stiks

[Monkey Wrench]

Got her on a short string last night, braced to 6", AND HOLY COW DID THAT MAKE A HINGE!  We'll see if I can tiller it out.  Still lots of weight to remove, so I'm giving myself a 1 in 3 chance.  We'll see...

[Monkey Wrench]

I was able to get the bow tillered, and work out the hinges.  This is one of my best tillers so far!  I'll post some pics up later tonight.  I've shot it a few times, and man do those arrows fly for being tillered down to 20 lbs @ 20".  

Onto the next phase, shaping the handle and applying the backing.

I would like to back it with silk or linen for strength, and then put a snake skin over that for looks.  Does anyone forsee any compatibility problems with that?

Also, I've been trying to find a thread that has a complete how-to that goes from live snake to snake-on-a-bow.  I'm piecing some stuff together, but do you know of a video or write-up where it goes through the entire thing?

Thanks!!!
Brad