tillering glass bow

[harry 62]

anyone use a tiller tree to get limbs balanced or just go with even to slightly positive tiller? if using a tiller tree should the riser be able to move thoughout the draw. when I try this my lower limb is always stiff.

[Crooked Stic]

Some guys  trace the bow thru out the draw then fold it in half and compare then sand  to get perfect limb timing. But I have found not necessary.. if your tiller is on and your eyeball can't see anything and you still got hebe jebes after the shot you may want to start over. 

[Kirkll]

If you have identical taper rates and wedges on both limbs, and use a pattern for getting the same width profile. These glass and carbon backed limbs rarely need much tiller adjustment, but fine tuning can be done with width profile and sanding.

Put it on the tree. Bring it to full draw, and at brace, then take a photo of it. If the limbs are bending in the same spots on both limbs, you are good to go. Just sand glass until you get an even tiller then test it out. Sometimes a little positive or negative tiller adjustment can take the buzz out if it exists.

Good luck….

Or like Mike was saying… you can trace the bow at brace height and half draw with a tiller stick on butcher paper. Then flip the bow over and compare them right on the work bench. It’s called “Mapping your limbs”…

I’ve never seen anyone fold the paper to compare limbs before, but I suppose that would work too. I just use my eye ball and can see the difference typically.

[harry 62]

I will give a try, most of my bows need very little tillering.read about ballancing or timing the limbs.for both limbs to come down to the same point at full draw I would have to take the lower limb past even tiller.I was looking to improve on good enough

[Kirkll]

I will give a try, most of my bows need very little tillering.read about ballancing or timing the limbs.for both limbs to come down to the same point at full draw I would have to take the lower limb past even tiller.I was looking to improve on good enough

Nothing wrong with fine tuning the tiller a bit... when i get mine to the point she looks nice and even and measures about even tiller, i adjust the brace to optimum preload with string length, then "thump the string" a few time by just drawing about an inch or so and letting it go. That's where you can actually feel a little buzz sometimes. Sometimes putting it back on the tiller tree and actually checking the tiller itself can help determine where a bit of sanding is needed.   NOT TILLER MEASUREMENT, but the bend in the limb..

Here is how most of the self bowyers actually tiller their limbs, and it can be done with a glass limb too.
Put one end of your block at the tip of the fades on each limb, and measure the distance. You can slide the block up the limb and check them too.

[Kirkll]

One more thing about limb balance that needs to be said. Its not so much what those limbs are doing at full draw that counts. It's more what happens after you drop the string. A bow with good balanced limbs will stop at the same time after Elvis has left the building.

Now where you will get a lot of debate going with different bowyers is that different  archers have different hand placement and different preferences to where they apply the pressure to the grip. For a straight grip often seen on ASL designs, and with the archer heeling down on the grip. This will effect the balance point on the limbs quite a bit vs a sculptured grip riser commonly seen on hybrids and RC bows where the pivot point, and pressure point is located at the deepest part of the grip with just the thumb pad and web of your hand making contact with the riser..... and that point is dead center between your tip notches.... 

You will read about all kinds of philosophy about using a shorter bottom limb and shifting the riser lower, to just tillering them with a stronger bottom limb. Good luck playing with those things. most of them rattle your teeth loose shooting them, and the performance sucks.

But..... and there is always a lot of butts out there.... You will find there are mitigating circumstances when it comes to string walking where typically guys with ILF limbs will tighten up those lower limbs a bit to balance things out.    .02 cents worth.

[Bowjunkie]

I do. I use the tillering tree to dynamically balance the limbs of glass bows relative to my holds... just like I do wooden bows. Just because the material is different, it doesn't negate the physics involved. If you do it, make sure you pull the string from where your string hand fulcrum will be. Don't just pull it from the center of the bow or handle. That doesn't even begin to tell us what we need to know. My fulcrum, near as I can figure, is roughly 2/3 of the way down my middle finger.

I usually tiller and balance a bow with the handle supported so that it's very unlikely to tip in the cradle. A vertical line on the wall mimics perfect fulcrum location and travel assuming both limbs are of equal strength relative to our holds. Imbalance is revealed by the hook(fulcrum) on the string drifting away from the line toward the stronger acting limb(again 'stronger' relative to our holds).

And yes, most bows are not tillered to be balanced, but rather with with the bottom limb 'too strong' for most folks. Meaning, they're tillered generically and archers are expected to be ok with it, or to 'fix it' by moving nock points, adjusting their grips, etc. That's just not how I roll when it's so easy to dynamically balance them. I have wondered how many archer's have never drawn a bow that was designed and balanced relative to their shooting idioms. I bet a lot.

[harry 62]

with handle supported with limbs parallel at brace the hook on string at a persons hold at full draw should the limb tips be parallel or is it the vertical line throughout the draw the only concern

[Kirkll]

For you guys getting serious about exact tiller adjustments and balance, and have concerns for where you place the hook on your string and how the riser is supported on the top, you can create a hook shaped just like your fingers fairly easily.  check these photos out.  This works pretty good.

https://photos.app.goo.gl/F5ok9hUCAKSHDABK8

[Bowjunkie]

Harry, the hook following the line is my main concern. That said, if the bow is of symmetrical design with same length limbs and the tips start at the same height, then they should come down the same distance if the hook follows the line.

The reason the hook following the line is my main concern is because I usually make bows with a shorter bottom limb, and many are selfbows whose limbs may not start off the same distance in front of the handle. I trust the hook & line to reveal balance in any bow. The line doesn't lie.

[harry 62]

do you have the arrow set square or how far above

Harry, the hook following the line is my main concern. That said, if the bow is of symmetrical design with same length limbs and the tips start at the same height, then they should come down the same distance if the hook follows the line.

The reason the hook following the line is my main concern is because I usually make bows with a shorter bottom limb, and many are selfbows whose limbs may not start off the same distance in front of the handle. I trust the hook & line to reveal balance in any bow. The line doesn't lie.