Help Needed - neck set, bridge height

[kencierp]

Darren,
Just trying to get the geometry of your guitar clear in my head --- so what is the angle of the sound-board to the body at the joint? Measured at that actual loction not the heel to fingerboard extenstion. BTW is the FB attached to the neck already?

[darren]

87.5 degrees.
FB is fretted and attached to the neck. This is a m/t bolt-on neck.

I'm with you, Ken, it doesn't make sense on paper. I tried a few photos but can't get one clear enough to show measurements, my macro setting isn't too good I guess.

875degrees.png

[kencierp]

OK -- so when you lay the straight edge on the finger-board it is perfectly flat on the frets with no rocking nut to extension? Also, have you applied "clamp pressure" to push the FB extension flat against the neck block with 100% contact with the sound board -- I assume that the fit of the heel cheeks is also perfect. Don't get me wrong I am not evaluating your work, its just that tiniest mismatches can cause gross errors at the bridge. BTW so far I think it looks pretty good.

[Darryl Young]

....... One more comment re: compensation for bellying. In set up I allow about 1/16" for the top to rise and the guitar to settle a bit after pressure from stringing. Not sure if that's what you meant. Good luck. Tom

Just to double check I understand correctly. Are you compensating for the top rising......or for the neck bending forward.......or both?

I'm guessing the measurements given are for a fretboard with no frets. If you have frets installed, how far should a straight edge lieing on the frets be above the bridge (or above the saddle) before you call the final neck set good and ready to string up?

[kencierp]

Can't speak and certainly won't speak for the other guys -- but if this were my guitar I'd be careful to work with its dimensions and not the "if comes" "theoreticals" or averages. Assuming that you have no rocking of the straight edge (mentioned above) with the frets installed the straight edge should brush the top of the bridge (be it .40" .35" .25") thick. Of course the neck must be adjusted perfectly straight as well with the truss rod. The misfit checks mentioned above must also be positve. With your situation 1/64 or so above the bridge is OK however if it is below the top of the bridge (and the bridge is already .25 thick that's a problem). Just visulize that if the top plane of the fingerboard hits the top plane of the bridge the saddle is going to be the same height above the bridge with the action set at the 12th fret. When you look at it in those terms the bridge thickness is a non-issue. If one does go with a thinner bridge on any guitar it is very important to have a little deeper and a little steeper ramps at the bridge pins --- this effectvely gets the string break at the correct angle.

[tippie53]

The fingerboard is a bit heavy but I think you are leaning the process. Ken's advice is sound and there isn't much I will add. Too many cooks spoil the broth. I think you are on the right track . Martin will actually desing 1 1/2 degrees into the side set so the top will have the angle in it .
Keep us posted and good luck

[darren]

sorry for the delay :) hard to get away from everything.

Ken,
All my measurements have been with the neck installed and bolted down - final resting place, so to speak. extension is tight on the soundboard, cheeks snug, etc. The straight edge is flat on the frets, (as I understand it after finishing/stringing up I'll introduce a bit of relief in the neck, though don't have the numbers in front of me. that's another post and another day) No offense taken, my work isn't perfect this is only #2 after all.

You hit the nail on the head - I'm trying to work the measurements and dimensions for this particular guitar - so it's a little tough when all you get (through books, internet, etc) are the theoreticals or averages. Your help is well appreciated. I've laid out a side profile of the guitar, nut to saddle with the measurements above in Illustrator, and it looks like this is gonna work and I may even have a bit of saddle to take off if I need it.

Darryl, I believe the top rises soon after stringing up, the neck bending forward only happens over a period of time depending on multiple factors. Someone more experienced can chime in on this, but it sounds like 1/16" rise in the top is a fair estimate.

John,
Your numbers posted earlier in the thread are noted and will be referenced in the future. Good Stuff!

[tippie53]

I am sure we are all looking forward to seeing the end results.