RD brace issue

[S.newman]

hey guys I'm building my 2nd RD laminated long bow and when I string it  seems to have different brace measurements at the fade out to the string ....is this something I can fix with tillering or is this a sign of unstable limb profile? any info will be appreciated as to why this is occurring and what I can do to fix it

thanks again guys learning a lot from this site
steve

[S.newman]

maybe play with the string length????

[Smguinnip]

I don’t believe that string length has anything to do with it. The limb on the right is stronger, I’m guessing you’ll find that the right limb is going to measure wider than the left limb, if not, maybe your tapered lams had slid during glue up causing one side to be stronger. Just a couple guesses.

[Smguinnip]

I like to lay out marks every 5” in each direction from the center of the bow and check the limb width at these locations to be sure that both limbs are symmetrical.

[Crooked Stic]

Was riser centered on form at glueup. Did the lams slip on glueup. Was the grind good on the lams. And yes check the Limb taper profile same on both ends. Or maybe you got the lams mixed up on glueup.
How much difference in measurments

[S.newman]

thanks guys I figure it out with yalls help
the riser did slip about .25 in which pushed the fade out creating a stronger limb even tho the limbs profiles were ground even within .010 all the way through at 5 different points measured
then I measured from cent to the very tip of the fade out and found my discrepancies

my next question should i just slowly work one limb till its even tillered ?
thanks again

[Crooked Stic]

Depends on how much its out. I have gotten an inch out without a lot of trouble. You can narrow the strong limb. Usally rouding corners am belly glass sanding. But if its real bad maybe not.

[Kirkll]

Welcome to hell brother!  Sometimes you'll get one that comes out way out of tiller for no good reason at all... I've seen them come out 1.5" out before and have everything top and bottom identical... When that happens it's typically the glass difference in thickness, and not having things matched up the same....

At this stage just trap the belly a bit more aggressively on the strong limb, then sand the hell out of it with 80 grit...

  When you get ready to lay things up and are checking your stack. always check your glass thickness very carefully.... i've seen glass as much as .006 difference in thickness from one end to the other on a 6' piece of glass before.  Cutting two pcs in half i always use one half of each piece for a limb, and flip one end for end, then match them up.  I never use the same piece of glass in one limb. THAT... can throw ya off big time...

  That's a little trick that will help your draw weight target consistency too.  .02 cents worth... Kirk

[S.newman]

thanks guys  you answered what I needed to know ill narrow it down just a touch more and then trap and sand the shit out of it and keep finger cross it comes back
if not then ill start over again

thanks again ill keep ya posted
steve

[Kirkll]

thanks guys  you answered what I needed to know ill narrow it down just a touch more and then trap and sand the shit out of it and keep finger cross it comes back
if not then ill start over again

thanks again ill keep ya posted
steve

Can i assume you are using .040 glass? You shouldn't have any problems balancing the limbs, but you are going to loose some draw weight doing it. What's the draw weight now?