My GR-1SF kit build

And now the doubt I really hope someone can help me with...

The next step will be to glue the neck to the body. But when I insert the neck on the guitar body and push it firmly, it leaves some gaps as I showed previously in this diary. I was thinking that I didn't need to do any major adjustments to it, but after the measurements, I became a little worried.

The alignment with the nut is straight but I don't think the angle is correct.

Let me show you.

Here's a picture of the alignment. I attached two strings (not guitar strings but I stretched them to get some tension and see if the alignment was correct).

Attachment 23414

Attachment 23415

Now, about the angle. I put my straight edge against the fretboard and, with the tune-o-matic bridge as lower as possible, it hits the bridge.

But worse. It hits in the upper side of the neck way less than it hits in the lower side.

Attachment 23416
(Upper side. It hits the bridge slightly)

Attachment 23417
(Lower side. It hits way more on the bridge.)

Now, what should I do?

I thought of an angled wood shim between the neck an the body but the neck fits so snugly on the body... To get room to rotate the neck and correct this, I'd have to file open so much the neck slot that I'm afraid I'll ruin it...

Can someone help, please? If I can't correct this I'll be able to have low action on only one side of the fretboard...

Hey Katuki, A shim seems like the easiest and best option. That won't affect the fit of the neck in the pocket as it will sit on the bottom of the pocket and only serve to raise the base. Now do you have access to wood working tools? A decent disc or belt sander will help dramatically in this endevour.

By the way, this really isn't as dire as it seems. It's fiddly, but not too difficult to fix.

I don't have to a disk or a belt sander but If I know what to do, I'd go to a carpenter's workshop and try to borrow some tools...

Hi Katuki from the photos it looks that you are measuring on the fretboard, are you taking into consideration the height of your nut string seat as part of your calcs of string height. Also its hard to tell from the photos but will your TOM studs go in any further they look like they have a touch more that they could possibly go down onto the guitar (but could just be the photos). I reckon you may be ok without having to do too much.

vh2580, when I tested the alignment of the neck, I attached 2 tuning machines and two yarns to them, and place them over the bridge with the necessary tension as if they were strings. What I found out was a high action, knowing that the bridge was on the lower position possible. I think this means that, even though with real strings it would be playable, I would never be able to lower the string height...

Here are the pictures of a straight edge against the fretboard from a closer look:

Upper side
Attachment 23418

Lower side
Attachment 23419

And the bridge studs are all way in and from one of the sides you can see this:

Attachment 23420

Help...

Hi Katuki

Have attached some pictures to explain. (apologies for the exceptionally sweat covered guitar)
Have a TOM bridge guitar so similar arrangement and neck geometry as your hollowbody.
Have pictured the action on this guitar which is not super low but not bad (I pick this one hard) and has room to adjust down.
The string geometry does relate to the fretboard but not entirely directly. You need to take into account the height of the string in the nut as part of your setup and if I lay the ruler on the frets as you have in your photos the ruler sits on the top of the bridge at the base of saddles not on top of the saddles as in yours. I think if you clamped your neck in and ran both E strings over under a bit of tension I think you may be ok action wise.

Thank you for your clear explanation.
I'll try to clamp the neck, attach some strings and adjust the nut height. Then see if the action is high or not.
But is it normal that one side of the neck is higher than the other? Or you believe it is the nut that's causing this diference?

I would look at it clamped and with the two strings on and adjust bridge to see what action is potentially going to be like. The guitar string will act differently to the twine. From there if you take some photos You can see if anything needs to be adjusted or not as far as the actual neck fit/angle. This will only be indicative but confirm if ok to continue with build ie gluing etc..
Any other adjustment of the nut etc. would come once your finalising the setup.

I'll try to do it, although it means that I have to screw the bigsby like bridge to the body so I can give some tension to the strings. I was hoping I would only have to do that after clear coating the guitar...