Have just finnished makeing a spline finder. On a 4 pcs.
blank is it alright to prebend the bottom section, then let
go,to find the spline(do to the stiffness of thr butt sections)
In the past have used a crystal wine glass, making sure it is
level,placing the butt sections on top, and they will role
to the spline. the spline being heavy will roll to the bottom.
Its realy hard to compress a short butt section on the
vertical finder. Any comments please as to this method!

The spine is the outside of the relaxed curve. Meaning that once pressured and the blank has moved to the "locked in" position the outside of that bend is your effective spine.

Butt sections can be a pain. If you cannot pressure it sufficiently to find the actual spine, I suggest locating the section's natural concave bend and marking the outside of that as your spine. It won't be exact, as the soft and stiffest axis a blank are rarely opposite each other. However, as the upper 2/3rds of the blank have the most influence on the spine effect, it should not throw off the upper sections which you have carefully spined. I think you will find it work quite well.

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What type of spine finder did you build? If vertical, how did you build it and what was the cost invovled?
Elrod

Elrod, you can make vertical spine finder with a wheel or bearing that you mount flat on 2x4 or what ever you want. Must be really free spinning,clean out grease and shields if bearing. Then make a cone shaped insert for bearing or wheel. I used two bolt flange bearing.Let me warn you don't try to to spine butt sections that are really stiff or you will split blank. The horizontal is much better and safer to use.I want to thank you for your feather inlays directions ,worked very well. Happy New Year all Ken.When I say wheel I mean one with bearing like roller blades ect.

Elrod, my wife was a machinist, just happen to find a live
center in her old tool chest. Bearings came from hardware store,
and a piece of 1*4 oak. Cost $10.00. Second choice was a counter
sink mounted same way. Need to dull the cutting edges.
Tom, any comment on wine glass splining
Happy new year

Anything that allows the blank to spin freely at each end will do the job. The freer it can spin, the quicker and more accurate it will be. I know one rod builder who sits his blank butts on a large marble and uses that for his "vertical spine finder".

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