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I think I have questions but sort of don't know what they are (does that make sense?)

Any chance you'd do a tutorial of your procedure Mario? I know I'd sure be interested.

Anyway, the procedure that I layed out above was what I thought would get me there, obviously not.

Dead Level is the key right? If it isn't dead level, don't glue the board onto the neck till it is? Am I right in this assumption?

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I think your method was fine, just needs refining. The more true everything is, the more true the outcome. If you consistently encounter some backbow, and it's consitent, modify your caul by shimming it the same amount.

Stay consitent; use the same caul, same clamps, same glues, etc..., time after time, and work out whatever inconsistencies arise mechanically.

Right on, thanks Mario. I'll keep at it, I've got lots of time and another 4 guitars on the go so I'm hoping it will work itself out. And I'll just keep asking questions if I run into any more snags.

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

"We have to constantly remind ourselves what we're doing....No Luthier is putting a man on the moon!" Harry Fleishman

"Generosity is always different in the eye of the person who didn't receive anything, but who wanted some." Waddy Thomson

One question about this operation - what type of caul do you use if you have a compound radius fretboard? With the jigs you are using to radius the fretboard with a router, I don't see how or if you can make a caul the full length of the glued area.

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Time is a great teacher, but unfortunately it kills all its pupils - Louis Hector Berlioz

Chansen / C hansen / C. Hansen / Christian Hansen - not a handle.

Christian

Bob Garrish made my aluminum caul...

But before that, all i had were two 1/4"x1/8" lengths of mild steel taped to my cast iron plate. They were set with the same taper as the fretboard, so they followed the compound perfectly; we only need to support the edges, as there's not a ton of clamping pressure with the epoxy. Shoot, before the iron plate, I used, for a long time, a 3"x4" hunk of hard maple that was planed very flat. I still have it around here somewhere...

Mario,
Another question if you don't mind. I've been thinking about it, and would it be possible to make a compound radius caul using the same jig for the fretboard? Basically flipping the entire jig up-side-down... or more specifically just mounting the router to the other side (now facing up) if you have enough space that is. Is my thinking correct that that should work?
Christian

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Time is a great teacher, but unfortunately it kills all its pupils - Louis Hector Berlioz

Chansen / C hansen / C. Hansen / Christian Hansen - not a handle.

Christian

Well, yes, something of the sort should work, but, it's unnecessary. Those two steel bars on the platen served me very well, and have only been surpassed by Bob's CNC'd prowess...

Sound good! Thanks,

_________________
Time is a great teacher, but unfortunately it kills all its pupils - Louis Hector Berlioz

Chansen / C hansen / C. Hansen / Christian Hansen - not a handle.

Christian

Here's that chunck of maple that served me well for a good many years, along with the two steel strips. Splay them out to match the fretboard, and spaced so that they only contact the last 1/8" or so of the fret, and tape them to the table/wood block/whatever flat solid thing you have. Place the tape where it won't be under a fret.... Clamp lightly and evenly along the neck's length..

And while I'm at it, here's a newly fretted board having an attitude adjustment. There's a 1/2" block at the nut end, and I used two 3/8" blocks at the other end on this one because it had a lot of bow. Always clamp in te center first, leave it a while(hour or more), then unclamp, look at it, and if there's another shorter bow, clamp at -that- bow's center. This is what's happening in this photo. As is often the case, there's more bow at the end, because there are more frets close together.

I just keep working the bow(s) like this, or by flexing with my hands, until she lays very, very flat on her own. It takes a bit of practice and experience, but it isn't rocket science... Perhaps if you all made up some scrap fretboards to practice on, you could see how much force you can use to work it, and not worry about breaking your good, expensive, nicely inlaid board <g> A little confidence goes a long way.

And this is what I like about this system VS fretting after the fact. We have the opportunity to work the whole of it, tweak as needed, shim, coax, whatever is needed. Otherwise, we're driving frets into a nicely flattened and radiused board, where they'll be trying to force the same backbow as we have here, leaving only the truss rod as your recourse.

That makes a lot of sense Mario.

I am using your techniques on three guitars currently, and the fretboards have stayed very flat after the clamping treatment, while waiting several weeks to get attached to their respective necks.