floyd rose intonation w/ new neck - HELP!

[jeremyo83]

I just fitted an American Kramer neck onto an old Yamaha RGX body... right handed neck, left handed body (photos below).
I've set up the floyd rose on it so that the bridge is floating level with the body, the strings are in tune, and the 12th harmonic is also in tune.

here's the trick.. the original yamaha neck was 2 frets longer than the Kramer I put on it, and when I play any chord with an open string, the open strings are completely out of tune... what can I do?

Can I intonate this trem system properly with the new neck? Will blocking the bridge fix this problem? What about putting a strat-style trem system in? Am I just SOL with this neck and need one the same size as the original?

HELP! (I'm supposed to use this guitar for new years!)

[jeremyo83]

uhh.. never mind. I just remembered that intonation should match the open string with the 12th fret (fretted, not harmonic), and it most certainly doesn't on my guitar. I'm going to try to intonate it properly now

[papacueball]

Hi, Jeremy. Sounds like your problem is the new neck. The 22nd fret is now where the 24th fret used to be, meaning you've lost about 3/4'' of scale length. A 24 3/4 scale length with the fret spacing of a 25 1/2 scale is not going to intonate correctly.

Just out of curiosity, what was wrong with the original neck?

Nice looking guitar, btw.

[ChrisK]

I measured your first pic at high zoom. The distance on the screen from the zero fret (it does look like you have one) to the 12th fret is 4.4". Extrapolating this one would expect the bridge to be located at about 8.8" from the zero fret.

The distance from the zero fret to the bridge is about 9.15" (this is a guess since the saddles are in different locations.

It would appear that you are indeed off "about" a good part of a fret interval at the 12th fret which would make sense if you used a neck with different nut (or zero fret) to heel length.

Also, I don't know what the scale length was on the original neck, but the new neck "looks" to be a 24 3/4" one (from the pic anyway) unless it is has a super-wide nut.

and the 12th harmonic is also in tune

I assume that you mean the 2nd harmonic around the 12th fret, and not the 12th harmonic.


Measure the string length from the nut or zero fret to the 12th fret. Twice that length is "about" where the saddles should be (the scale length).

Measure this for both the new neck and the old neck. Also measure the length from the nut or zero fret to the end of the neck heel. Write it all down and post the info for the scale length and heel length.

A little math will tell us if'n you have a chance at finding a paddle (you're already "up the creek").

[jeremyo83]

thanks, both of you.
I tried to intonate, but as you probably already know, there was no way for me to adjust the bridge to compensate for 2 missing frets and different scale.

papacueball, the original neck severely needs to be refretted. I was just going to do so, but my friend offered me this old Kramer neck, and we were getting a kick out of the 'shark fin' effect. we're pretty bummed that it's not working out. thanks for the compliment - it's my first try at anything like this, so I'm pretty pleased with it. the final clearcoat (on closer inspection) could use a little work, but other than that, it's great.
I know I can use the original neck on new years, but because of the fretwear, i'll have to bend the truss back and have wicked high action until I can refret it in the new year. it's mostly a backup guitar at this point anyways.

I would, however, still love to use this neck because of the asthetic of the headstock, so ChrisK, I will take those measurements and post them tonight. We'll see if we can find me a paddle or not.

ps.. Chris, the middle pickup on this guitar is inactive, just filling a hole. What are the chances of removing it, routing out room for the neck HB near the mid position, and moving the neck down to where it needs to be? (by this, i mean, figure out how far the neck needs to move toward the bridge, and rout a new HB position as close to that neck position as I can so the bridge and neck Pups don't sound too smiliar) .. all theoretical right now, it might be less work to just refret the old neck, but like I said, I like the shark fin.

[jeremyo83]

pps..

ChrisK, I didn't have a chance to measure the necks last night, but if it helps, I had time to compare the new Kramer neck to a Strat neck I have lying around, and they are the same size and scale. The yamaha neck, like I said before, is 2 frets longer and the scale is larger as well. I figure it's about 1" - 1 1/2" longer than the Kramer, but I'll measure it tonight.