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I, with the help of another first-time builder, spent what seemed like an inexorbinant amount of time last night trying to get my neck joint right. It's a simple bolt-on neck, so it couldn't be that difficult, could it? It was. I think part of the problem in getting the neck angle, side-to-side angle, and the neck flush with the side of the guitar probably stems from the geometry of the body, neck block, etc. being slightly out of kilter -- more of a first-time builder problem than anything.

I got the neck angle and side-to-side angle set pretty well (as best I could tell from not having done it before). However, the heel of the neck does not make nice flush contact with the side of the guitar. At this point trying to fix those small gaps would throw the other geometry out of whack, so I'm hesitant to go back to square one. It's purely costmetic -- should I just chalk that up to experience and strive to do better next time, or is there any way to fill those gaps without redoing the neck set all over again?

Cheers,
Mark

Mark did you undercut the surface that contacts the bobdy so that only a narrow edge touches?

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[QUOTE=Bobc] Mark did you undercut the surface that contacts the bobdy so that only a narrow edge touches?[/QUOTE]

Yes, I did remember do to that. It helped a lot. Actually what I think I did was rounded the surface that contacts the body, which creates the small gaps at the edges of the heel of the neck.

Well you could try putting a piece of PSA adhesive on the body and lightly sand the contact area again trying not to rock the neck. Or have you done this too?

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[QUOTE=Bobc] Well you could try putting a piece of PSA adhesive on the body and lightly sand the contact area again trying not to rock the neck. Or have you done this too?[/QUOTE]

Forgive my dumb question, but what is PSA adhesive? I haven't added anything to the body and sanded it smooth, but it sounds like it could be an option.

PSA = pressure sensitive adhesive...as in self stick sandpaper... by attaching that to the body as Bob suggested you can sand just where needed and most times that is enough to give you the relief you need to get the joint tight...

One of those tricks of the trade.

[QUOTE=Shawn] PSA = pressure sensitive adhesive...as in self stick sandpaper... by attaching that to the body as Bob suggested you can sand just where needed and most times that is enough to give you the relief you need to get the joint tight...

One of those tricks of the trade. [/QUOTE]

Okay, got it. Thanks. Any suggestions on sources for PSA?

I had a really hard time getting the job done quickly on the first few I did too... Here are a few things that worked for me.
1) make sure the body is FLAT at the neck joint area.
2) as mentioned, cut back the edges, leaving 3/16" or so to be sanded.
3)I use 60 grit cloth backed abrasive ripped into 1" wide strips. (Make 'em about a foot long) for the first stage of sanding. I go to 220 for the final step.
4) I get the angle & setback sanded in accurately before glueing on the fingerboard or the heelcap. This allows for a longer stroke with the sandpaper & more even material removal.
5) I never pull the paper all the way trough the joint. Everytime I did this, I would oversand the back edge, causing it to curve away from the body... (Leaves a gap)
6)Make sure the little unsanded bit behind the tennon is not interfering with the fit. I just chisel it away when necessary. Any gap here will be covered when you glue on your heel cap later.
7) Before I started using cloth backed paper, I glued my sanding strips to a strip of card paper (bristol board). This made it easier to control & allowed the use of greater downward pressure without ripping the sandpaper.
8) For a gap free fit of the heel cap after all the fitting has been finished & the fingerboard is glued on... Bolt the neck on securely & do a final check for alignment & setback. Stick a piece of sandpaper to the body where the cap will fit.
Leave the cap blank a little oversize & work it back & forth across the sandpaper while holding it down onto the heel firmly.
Once you are happy with the fit, remove the neck & tape a piece of saran wrap over the body where the neck will fit. Cut the film so you can bolt the neck back on without causing any wrinkles. Then glue on the cap. The saran wrap will mask the glue away from the body.
Scotch tape or packing tape works even better than saran wrap. Just don't laeve any gaps or you'll end up steaming the neck apart!
This is just stuff that works for me... I hope it is helpful. Good luck.   Dan

[QUOTE=ms960] Any suggestions on sources for PSA?[/QUOTE]

Lowes, Home Depot. Look in the section where the sandpaper is for Random Orbital Sanders.Roy O38923.4733333333

Thanks very much guys. I'll try to locate some PSA and see if it will solve this problem.

Or do the old pull the sand paper trick. Lay 320p on the side, grit toward the neck, fit the neck to the mortise, slowly pull the paper out and down. this will sand the cheek to match the side.MichaelP38923.5184606481

[QUOTE=MichaelP] Or do the old pull the sand paper trick. Lay 320p on the side, grit toward the neck, fit the neck to the mortise, slowly pull the paper out and down. this will sand the cheek to match the side.[/QUOTE]

That's exactly what I did on number 2 after following Hesh's advice. Works like a charm. It's called 'flossing the cheeks'!

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[QUOTE=MichaelP] Or do the old pull the sand paper trick. Lay 320p on the side, grit toward the neck, fit the neck to the mortise, slowly pull the paper out and down. this will sand the cheek to match the side.[/QUOTE]

Won't this change the neck geometry, however?

When doing the pull technique, you sometimes have to pull sideways out from the top of the heel, near the fretboard - as well, when the fit gets really close, I bolt her up and check the alignment again side to side with the top centreline. Also sometimes there is a spot about 1/2 to 1 inch away from the FB on the heel that prevents the very top from seating tight - I take a chisel here and SHAVE right in that area, angling the chisel in and down a hair, and the top area comes right in - amazes students everytime I show them this. You can do this, its not that tough, just go slow, keep checking - thats the critical part.

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That's why i do most of the flossing before I put on the fingerboard. Don't have that high point to chisel out.
Diff'rent strokes... (please excuse the intentional pun)

[QUOTE=ms960] [QUOTE=MichaelP] Or do the old pull the sand paper trick. Lay 320p on the side, grit toward the neck, fit the neck to the mortise, slowly pull the paper out and down. this will sand the cheek to match the side.[/QUOTE]

Won't this change the neck geometry, however? [/QUOTE]

Every thing you do is changing the geometry. The trick is to change it to the desired result. You can't just go at it willie-nillie and expect the right result. As Tony said some times you have to pull from the side to remove material at specific spots, and you want the neck to be at the right angle when you do either. I bolt the neck in place just tight enough to allow the paper to move (sounds counter intuitive but its not) and make one stroke, then check everything out carefully and repeat as needed. It is easy to go too far so check the fit regularly. You do not want more than 1/8"-3/16" of cheek in contact with the side or it gets real hard to fit any neck up.MichaelP38923.6033564815

Is the heel touching the side? Is sanding what you need. The picture I got from your post was that there is a gap all around. If that's the case, your tenon might be a tad too long. Maybe I misunderstood.

Ron

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Ron I think but could be wrong that the heel cheeks has inconsistent touch-out due to sides not being true perpendicular.

cupping of the sides should not be an issue as the sides would be glued to the block so it has to either be that the block is installed out of square thus causing the sides to taper one way or the other, or Ron your theory is right. the tenon is too long for the mortise.

Mark if this is the case then shorten the mortise back till you have 3/16 clearance from the mortise and the tenon when the cheeks touch out. you do not want the tenon to touch out to the bottom or inside face of the mortise.

Hi Mark, I'd recommend getting the Stewart MacDonald video on Resetting Necks, or Neck Setting... cant remember the exact title...   It's also available to rent from Technicalvideorental.com for $10. It goes into great detail on what sandpaper grits to use, how to line things up, etc. It helped me a lot.

Mark, can you shoot a pic that shows the size of the gap you have to compensate for. That would be helpful, to see where you are at this time.

Mike
White Oak, Texas

I am assuming that you did get the tenon seated and you still have a gap??????

Mike
White Oak, Texas

My post is not going to help you - just want to thank you all for this feedback, as I am just reaching this stage on my first guitar, and am expecting it to be a challenge. This has all been so helpful.
Frank

To MichaelP - well I had my first "cheek flossing" experience tonight, and what a buzz it was. I followed your steps to the letter and it worked like a charm. Very rewarding step in my first guitar build.
I also used someone's suggestion to glue various grades of sandpaper to cardboard - that was also helpful.
Thanks to everyone.
Frank