bare shaft knock left and high TD recurve

[Radmcg]

I have been working with 2 bows I built. Both fiberglass laminated limbs from Bingham laminating presses. A 66" longbow #46 pounds at 28" Tiller 1/4 positive. My draw is 28 1/2. Bare shaft tuned with 30" 600 spine with 137 grains up front point and insert.
Now the problem 60" TD recurve #55 28" everything I try is nock high severe and left nock bare shaft.  It finally tunes close left to right with an old 55-75 gold tip at 30" with 137grains insert and tip.  Tiller is even. 8" brace.  Shoot 3 fingers under.  Tried lowering nocking point from 1/2 high to 1/8 high still nock up.  Measured the serving @.13 same as other string.  So nock is not to tight.
First don't believe a  #55 recurve needs a 55-75 (roughly 400 spine) 30" arrow with 125 point to tune left to right. no limb twist.  Almost true center shot arrow rest cut out shot off the shelf.
Second why no response to lowering the nock.  I have read weak spine can shoot left nock and high due to flex but a 400 shouldn't be that weak at 30" with 125 grain point.  Should I try going higher with the nock (it was at 1/2 " to start) and place another nock point under the arrow since I shoot 3 under? 
Is it the tiller?  If not what is causing this?  Just don't want to go sanding on the glass if it's not the tiller.
If so what is the best way to fix?  It has .040 glass that has not been sanded.  I have read mark glass with marker and sand.  Back or belly of the limb first?  I also thought it might be my form with the higher poundage bow but don't think my form is that bad and I have a JK Chastain that I shoot fine at #55.
Any ideas appreciated.
Rad

[Roy from Pa]

Tried lowering nocking point from 1/2 high to 1/8 high still nock up.

Nocking point could be too low and arrow is bouncing up off rest.


When bare shaft testing, all you worry about is the point of impact.

Proper way to do it is shoot a couple bare shafts along with a couple fletched shafts.

If the bare shafts group with the fletched shafts, then all is good.

If they group to the right of the fletched shafts then they are weak in spine.

If they group to the left of the fletched shafts then they are stiff in spine.

If they group high, then raise your nock point.

If they shoot low then lower your nock point.

That is for a right handed shooter.


https://www.youtube.com/watch?v=BSJ6-HjPMTM


In the link below, scroll down to the bare shaft planing section.

https://www.fenderarchery.com/blogs/archery-info/basic-tuning

[Radmcg]

Thanks Roy.  I will look at that tomorrow when I'm  off.

[Roy from Pa]

Ok and definitely add another nocking point below the arrow.
I shoot 3 under and my nocking point is usually 5/8th high and some guys are even higher.

[Radmcg]

Ok watched Ken Becks video.  That was a great in depth explanation. especially the nock high part.
Thanks Roy.

[Roy from Pa]

Welcome...

Sent you a PM....