Border limb vibration?

[yellowgazer]

Hi

I shoot a pair of medium Border TXG's and like them very much. Not that it seems to affect my shooting (averaging 275-280 of 300 on indoor 18m/40cm face), I have noticed that for 1-2 seconds following the shot, the string moves "up and down".

Now, I know that the string doesn't move by itself (clever me ), so it is of course due to the limbs. Sid at Borders says it can be tuned to go away, but how? I have tried a lot of different tiller settings, but to no effect

My setup otherwise is a Merlin Quazar with the Merlin Active Balance stab&v-bar. ACE arrows.

[buzz lite beer]

tiller adjustments and nocking point adjustments can reduce the effects of after shot limb wobble, what your experiencing is usually down to one of the limbs travelling to its forward most point of travel faster than the other. for me the best way to reduce such effects is to hold the bow as deep in the grip as you can draw the bow back as level as you possibly can along the vertical plain, then observe how your long rod or sight reacts, if the rod/sight rises this indicates that the top limb is slightly stronger than the bottom one so back the top limb off a quarter of a turn and increase the bottom the same this will maintain your current draw weight and conversely if the long rod/ sight dips down apply the reverse.

[King Custard]

I got the distinct Impression that Tony at Perris' wasn't a fan of my Border XP's causing the same up/down thing. I think the faster a limb is - the more you'll notice it,
Like you I tried many tiller adjustments to lessen it- and to some degree it is now lessened...still not perfect but very close.
But to be realistic, at my level, what does it matter if it does vibtrate up and down just a little bit - when it's the same for every shot I take isn't it?. I dont think I've got the patience to find the perfect 1/16 th turn of a tiller bolt- to then find that grouping is actually improved by having a slightly different tiller setting anyway.
Like brace height - i find my arrows leave and shoot cleaner when my bows brace height is NOT set to it's quietest point.
Maybe like you I'd LOVE a perfectly 110% tuned bow, but not having that same perfect degree of skill myself, I doubt I'd appreciate it anyway!

[yellowgazer]

I agree, but

Originally Posted by King Custard

when it's the same for every shot I take

how can one be sure? There is a lot to be said for confidence in your equipment ...

Come thursday, I'll check out buzz's method.

[buzz lite beer]

Originally Posted by King Custard

But to be realistic, at my level, what does it matter if it does vibtrate up and down just a little bit - when it's the same for every shot I take isn't it?. I dont think I've got the patience to find the perfect 1/16 th turn of a tiller bolt

May I ask Why buy top end kit like a Nexus and XP10's if your not getting the best from them, striving to eliminate basic irregularities from your kit puts the emphasis back on the archer and their form, at any level with a bit of work things can be improved somewhat. You get out what you put in, for example like Old Blokes recent thread on finger tab issues, it's only affecting a few shots, but that's a few shots too many.

[JohnK]

Tiller adjustment - any limb of any type will wobble if the tiller doesn't suit your style of shooting and the rest of the set up.

My experience is that zero tiller does not work well on Border limbs, and in fact causes excessive vibration. Both my 70in XP10s and TX40s work well around +1/4 to +3/8in, and I get little vibration even when I shoot barebow without any dampers.

Remember also that tiller adjustment, nocking point height, bow grip pressure point and stabiliser balance are all related. Only change one at a time.

EDIT - oh, and bracing height

[Prockers]

I'm using a new pair of TXGs, and found the best way of sorting that problem after making the nocking point about 2mm lower than it should, is to mess with the bracing height.

[yellowgazer]

Based on buzz's method above, I'm up to a healthy 10mm (~3/8") positive tiller, the stab doesn't move when I draw back, but the vibration hasn't gone yet (maybe a tiny bit better).

But, hey, I did manage to shoot a new PB of 333/360 on 30m indoors, so I guess it's not all bad

Brace height is currently 22.5cm, do you think it should be higher/lower?

[Prockers]

I've got my tiller at 3mm +ve, and with a lower nocking point there's no vibration after the shot now i got the bracing height to about 205mm. Borders do all brace a lot higher than all other limbs!

[yellowgazer]

Originally Posted by Prockers

I've got my tiller at 3mm +ve, and with a lower nocking point there's no vibration after the shot now i got the bracing height to about 205mm. Borders do all brace a lot higher than all other limbs!

Do you think that a high nocking point causes the vibration (or is a factor) ? I use a Beiter rest, which by nature likes a high nocking point (mine is +1.8cm; bare shafts hit same as fletched at 18m)