I took out a 60# PLX longbow to shoot today, found the arrows and strung it up. The top limb curve is not symmetrical to the bottom limb. I thought maybe it would even up with shooting and stringing. Shot about two dozen arrows, and they were flying all over the place, which is abnormal for me. I thought maybe leave it strung overnight and the limbs would settle, but decided against it.
You can clearly see the limbs have different curves still. I could see the string was at a funny angle relative to holding the grip vertically. Top limb curves more and bottom limb has a shallower curve.
I sent an email to black Widow to ask them as well.The bow was stored indoors in an MTM carry case, arrows on one side held by foam inserts and the limbs of this take down PLX are kept in flannel sleeves and secured in the same foam as the arrows opposite them. Bow has been in it more than 10 years. I'm stumped.
The second pic shows the upper limb on top, a check of the tiller (perpendicular measurement) from the string to the fade-outs should show the upper tiller 1/8" to 3/8" greater than at the bottom limb (verify with the mfgr). Assuming the bow was in
a case that prevented moisture, or prolong heat above 90 degrees I don't see where there is a problem. I would check the string alignment. If your arrows are fish-tailing at 10 yds, check the nocking point. If the arrows are nock left they might be too stiff and vise-versa for a weak spine. Then check the spine, straightness, and if the nocks and points are on straight. The serial no's should be the same for both limbs. Check the string height based on the mfgr's recommendation. Last question, have you changed your shooting style from split finger to 3 under or vise-versa?
The limbs will not have the same curvature, if the lower limb is shorter. The center of the bow is probably at the throat of the grip and handle.
If the tiller is any higher than the 3/8" mentioned by Hud, that could be a concern. If the tiller is changing over time, or if there is any limb twist, that would be a major concern. Limb twist in a longbow is rare, almost unheard of, so if there is any limb twist or if the tiller changes over time, it could be an indication of a structural failure within one of the limbs. To check for limb twist, with the bow strung, hold one end of the bow in one hand and rest the other end on the floor so that you can sight down the length of the bow. The string should track down the center of the bow from limb tip to limb tip.
Since you probably don't have any baseline measurement of tiller, just measure it now as Hud suggests and check it from time to time over many hundreds of shots to see if it is changing.
60 pounds is a lot of bow, and unless you regularly shoot that weight, it may be impossible to shoot it accurately.
Ok so after a quick check with BW, this bow is tillered for three under. I do not know how I ended up with that tiller, as I have forgotten much since 2009! 60# doesn't bother me very much but I shoot split finger, always have. BW says for three under tiller this limb geometry is normal. Not sure what I do but BW will know. Typical grouping for me at 15 yds just a minute ago with the PCHXC 49#...aside from the tiller maybe arrow spine is wrong or draw is reduced........I'll report back.
And so I took out the PLV which shoots fine, spoke to BW, and this one is also tiller for 3 under. I've had it equally long as the PLX. Hmmmmm.
Both are on the way to BW for re-tillering and refinish. I'll post pics when they get back.
Sounds good, it will be easier to sell one if you decide to. BW will do a good job and you'll be a happy shooter. Both are popular bows.