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I have been working on a few bar fret jobs recently and I wanted to find out if any of you have any good tips for controlling the neck relief when you are done fretting.

I find that I usually have a back bowed neck after installing all the frets and wind up having to go back and skin down the frets in the middle of the neck to ease up on the compression.

If the neck has too much relief I do the opposite and shim and/or replace frets in the middle of the neck with a wider fret to increase the compressions by some amount.

Either way I feel like my approach is a bit too heavy on the guess and check. There must be a better way.

Thoughts?

_________________
- Louis Freilicher

Oh No! Not another learning experience!

Maybe there is, but I don't know about it. The guess and check, mixed with a
bit of intuitive judgement, and a lot of close monitoring as the frets go in is
still the best method I know of. You can use general rules and formulas for
basing wire size on slot size, type of wood, condition of slot, stiffness of
neck, and so on are just too big of variables. I haven't given it much
thought, but no simple jigs or measuring devices come to mind that would
make a huge difference.

Slow and steady, evaluate, proceed, re-evaluate, move to the next fret, etc.
I'd like to know a better method as well, but I'm not sure if one's out there.

_________________
Eschew obfuscation, espouse elucidation.

David,

That's about what I expected; trial and error, experience and intuition.

I have been thinking about a rig using three gauge blocks and a straight edge to look for back bend as you fret.

I.E. Shoot your board straight and start fretting from the middle of the neck (say 4-9). Then lay a block at 12, 6 and 2 and with your straight edge on the gauge blocks, check to see if you sprung the neck back. I guess the stew mac relief gauge could give you the same info as well.

Do you have a rule of thumb for bar wire size vs. fret slot size for the average neck?

Thanks for you input,

Louis

_________________
- Louis Freilicher

Oh No! Not another learning experience!

You want to have a number of sizes available. Compression fretting , if it is bar or tang is still done with the same principle you want to have a slot overfilled .
   This is not rocket science but you need to use some common sense. I like to fret so the 7th fret up is fairly flat , Then from the 7th back I want to see about a .006 to .009 back bow.
   This can usually set you up with a good relief on string load. If the neck is on the guitar you can check this by locking the headstock and use about a 5-6lb weight on the body. This gets you pretty close to a full string load. You can then check your progress as you fret. I also start at the 14th fret and work to the nut.
john hall
blues creek gutiars

The notched straight edge that Stew Mac sells is excellent for this, and I do
use my neck jig as well. I've not used it, but it seems dial indicator on the
straight edge would be good for this as well.

To be honest though, it's been well over a year - maybe closer to two - since
I've seen a bar fret job. I really don't remember what I last used as a slot/bar
size ratio. I don't even have any bar fret stock around my shop right now. I 'd
probably start with around .002" over the slot size and go from there. I'm
lucky enough to have access to a really nice and precise steel rolling mill
from a neighbor upstairs when I need it, so I can make my own wire if I need
it.

_________________
Eschew obfuscation, espouse elucidation.

On occasion I have brought bar fret wire to a jewelers and used their rolling mill to decrease the guage a bit if the fit seemed too tight and that excessive backbow would result from its installation in a particular instrument.

The one advantage of bar wire is that if there is a little positive or negative relief after the installation, this can often be remedied by

leveling with a flat file before you crown.

Otherwise it's pretty much by feel...............