Official Luthiers Forum!

Solely owned and operated by Lance Kragenbrink
It is currently Sat Nov 18, 2017 4:15 pm


All times are UTC - 5 hours





Post new topic Reply to topic  [ 18 posts ] 
Author Message
PostPosted: Tue Jan 12, 2016 9:49 pm 
Offline
Walnut
Walnut

Joined: Mon Dec 14, 2015 9:35 pm
Posts: 24
First name: Jeff
Last Name: Duncan
City: Concord
State: Ma.
Zip/Postal Code: 01742
Country: USA
Focus: Build
Status: Amateur
So I have a Yamaha guitar that I bought in a pawn shop some 20 years ago for $125. I've gotten my use out of it for sure but when I started really playing again last year I remembered how difficult it was to play. Always liked the sound, but was a bear on the fingers. Over the last year or so I've been reading up and learning a bit about how to check and correct certain things on acoustic guitars and went through the truss adjustment, reduced the height of the saddle and even went to lighter strings but the action on this guitar was still too high. With a straight edge on the fretboard the end hits the bridge about 5/32" or so below the top. So I decided a neck reset, as well as a re-fret, was in order, but come to find out Yamaha's use epoxy on their necks so steaming is out, which means sawing it off fully and bolting back on. So things went pretty smoothly until I got the neck completely off. That's when I learned several things.....1st, for some reason I always though this guitar had a solid top.....nope, it's plywood! 2nd the dovetailed pocket on the guitar is plywood! Neither of which are real issues, just disappointing I guess.

So the issue is this, I planned on drilling through 1 side, (bottom of course), of the heel of the neck, inserting a couple threaded steel dowels perpendicular to the length, and then simply bolting the neck and plugging the holes with mahogany plugs. Presto, bolt on neck complete!.....except that there's a wood dowel already in the neck!!! I can't quite figure out what it's for, (maybe aligning the heel to neck before they were glued?), but it runs vertical in the heel of the neck right where you'd want to bolt it, and is large enough that I don't think I'll have enough virgin wood to confidently secure the neck with bolts? I haven't read about this in my research so am a bit surprised.....has anyone else run into this? If so how did you proceed? I'm thinking I might just make a new neck for it at this point copying the fret positions from the original.

Jeff


Top
 Profile  
 
PostPosted: Wed Jan 13, 2016 3:18 am 
Offline
Cocobolo
Cocobolo

Joined: Sat Aug 31, 2013 10:58 pm
Posts: 139
Location: usa
First name: george
Last Name: s
Country: usa
Focus: Repair
Status: Amateur
I followed this guide from frets.com, on a guitar with mystery glue, maybe this will help: http://www.frets.com/FretsPages/Luthier ... eset1.html


Top
 Profile  
 
PostPosted: Wed Jan 13, 2016 9:55 am 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Tue May 13, 2008 10:44 am
Posts: 3142
Pics would really help.

BTW you can still steam off an epoxied in neck. I've done bolt on conversions a few times and it works quite well. I use a Japanese flush cut pull saw to get the neck off. The few I have done have not had dowels go vertically through the heal but one of then did have dowels orientated perpendicular to the heal acting just like bolts would. If I understand you correctly there is a dowel that runs perpendicular to the fretboard and through the heal? If so I would just drill in the female threaded inserts and carry on as normal.

Also, no need to plug the bolt holes in the neck block. You might need to unbolt the neck again some day.


Top
 Profile  
 
PostPosted: Wed Jan 13, 2016 9:42 pm 
Offline
Walnut
Walnut

Joined: Mon Dec 14, 2015 9:35 pm
Posts: 24
First name: Jeff
Last Name: Duncan
City: Concord
State: Ma.
Zip/Postal Code: 01742
Country: USA
Focus: Build
Status: Amateur
So the dowel does run vertically perpendicular to the fretboard.... looks as if they used it possibly to line up the heel block to the neck for gluing? But now that it's been cut it's right at the edge of the heel and it's not the tightest hole. Probably why they used epoxy on these guitars....to make up for sloppy joinery!?!? I'm not sure of the name, but I'm not using what I think of as threaded inserts....the ones where you have to screw the insert into the wood. I'm planning on using a small steel dowel with a hole drilled and tapped through perpendicular to it's length....think something like an Ikea fastener. I drill a hole into the side of the heel to slide it in, and a hole perpendicular too bolt through the guitar body. Once it's installed into the side of the heel I can plug it b/c it allows me to bolt and unbolt the neck without needing access to it.

Anyway I'm going to try and post a couple pics so you can see what I'm dealing with....
Image
Image

thanks,
Jeff


Top
 Profile  
 
PostPosted: Wed Jan 13, 2016 10:20 pm 
Offline
Brazilian Rosewood
Brazilian Rosewood

Joined: Tue May 13, 2008 10:44 am
Posts: 3142
Wow that is ugly. I can't imagine why they would do that unless it's like you said, to light it? Did you remove the tail from the neck block? I'd be tempted to just fill in that area around the dowel with some good epoxy and just drill the inserts in. I think what you are talking about is barrel nuts and bolts? Why use those in this particular case? If you use the bolts as shown in the first image here then you won't need to fill holes with plugs:

http://www.lmii.com/products/mostly-not ... ck-inserts

The barrel bolts are the last image but work in a mortise tenon joint not a butt joint.


Top
 Profile  
 
PostPosted: Thu Jan 14, 2016 9:45 pm 
Offline
Walnut
Walnut

Joined: Mon Dec 14, 2015 9:35 pm
Posts: 24
First name: Jeff
Last Name: Duncan
City: Concord
State: Ma.
Zip/Postal Code: 01742
Country: USA
Focus: Build
Status: Amateur
Yeah the tail was pretty easy to remove using a mortise chisel and taking small chunks at a time. I was thinking originally that the barrel nuts would be a safer bet for future disassembly. I figure mechanically they should work fine for a butt joint, but just not as clean since they have to be installed from the side. This is going to be a beater guitar to have around the shop so the couple plugs on the bottom side of the neck wouldn't bother me. And since I'll re-finish the whole neck anyway most people wouldn't even be able to pick them out. However I'm re-thinking and may possibly go with the inserts after all. With the way this silly dowel sits it may be a more secure system in the end.

thanks,
jeff


Top
 Profile  
 
PostPosted: Fri Jan 15, 2016 2:44 am 
Offline
Cocobolo
Cocobolo
User avatar

Joined: Mon Dec 28, 2015 10:15 pm
Posts: 110
Location: South Bend IN U.S.A.
First name: Bob
Last Name: English
City: South Bend
State: IN
Country: U.S.A.
Focus: Build
Status: Professional
You think that's bad, take the neck off of an 80's early 90's Les Paul, they have a dovetail on the heel of the neck and a round hole in the body which they fill with a huge amount of epoxy and shove the dovetail in.

If you have tapping equipment, you can tap a few 1/4/-18 (or whatever size looks right) threads into the heel and through holes in the heel block. epoxy the threaded rods into the neck heel. they won't go nowhere. Lining them up is the hard part though, and drilling through the heel and plugging them will be one way to make sure they line up, but not the most aesthetically pleasing, unless you get creative with it. Not sure if they make a power drill small enough to fit through the sound hole, including your hand!

One thing you have not mentioned is that you will have to put a slice of wood in between the heel and block, to make up for what the saw and straightening it out removed too, or else risk bad intonation.

_________________
If what you see is what you get, then Stevie Wonder ain't got nothin'!


Top
 Profile  
 
PostPosted: Mon Jan 18, 2016 11:27 pm 
Offline
Mahogany
Mahogany

Joined: Wed Dec 16, 2015 6:50 pm
Posts: 63
First name: Tyson
Last Name: K
City: Stony plain
State: Ab
Zip/Postal Code: T7Z3A1
Country: Canada
Focus: Repair
Status: Amateur
What's the model of the guitar? I have an fg 180 that may need a reset in the future. I hope it does not give me that much trouble...


Tyson k


Top
 Profile  
 
PostPosted: Tue Jan 19, 2016 11:14 pm 
Offline
Walnut
Walnut

Joined: Mon Dec 14, 2015 9:35 pm
Posts: 24
First name: Jeff
Last Name: Duncan
City: Concord
State: Ma.
Zip/Postal Code: 01742
Country: USA
Focus: Build
Status: Amateur
I think it's a 335? It's definitely a 3** and at least 20 years old and possibly older. I guess you can still try to steam off the epoxy? I had just read a bunch of threads that said the stuff doesn't budge and cutting the neck off is the way to go so???? It's also definitely a guitar that's not worth spending money on....but I like the sound enough I figure it's a good learning experience so why not.

I did glue on a slice of wood. It's not perfect, but grain was similar enough that with stain and finish it will mostly disappear from any distance. Then again it will be a shop guitar so not nearly as worried about the look as the function. I'll replace the heel cap as well so it doesn't look so goofy. Image
I'll also say that the finish on this, (polyester I think?), is damned near bullet proof! That stuff really takes some effort to get off!

Jeff


Top
 Profile  
 
PostPosted: Wed Jan 20, 2016 12:58 pm 
Offline
Cocobolo
Cocobolo
User avatar

Joined: Mon Dec 28, 2015 10:15 pm
Posts: 110
Location: South Bend IN U.S.A.
First name: Bob
Last Name: English
City: South Bend
State: IN
Country: U.S.A.
Focus: Build
Status: Professional
JeffD wrote:
I'll also say that the finish on this, (polyester I think?), is damned near bullet proof! That stuff really takes some effort to get off!


Although it is an older instrument, I have yet to have to strip down an American made one with a hard finish like the ones coming from across the pond. I just had to rasp and sand a near 1mm thick glass like finish off of a Korean made bass, because Citristrip did absolutely nothing, and it works great on most any finish.

Good job on the added wood slice Jeff, looks like it will blend right in. Every bit of meat will count in putting it back together.

At the Samick guitar plant in Korea they spray a couple thousand electric bodies a day, on carts of 30 each out back of the plant with a sprayer more akin to a fire hose fed by a 200 gallon tank. They put on two coats, one for color and one for clear. the stuff goes on so thick that they are leveled in a series of thickness sanders. The jungle area behind the plant has a huge dead zone that looks like a Jackson Pollock painting. The average life expectancy of the workers is ~45.

_________________
If what you see is what you get, then Stevie Wonder ain't got nothin'!


Top
 Profile  
 
PostPosted: Thu Jan 21, 2016 9:29 pm 
Offline
Walnut
Walnut

Joined: Mon Dec 14, 2015 9:35 pm
Posts: 24
First name: Jeff
Last Name: Duncan
City: Concord
State: Ma.
Zip/Postal Code: 01742
Country: USA
Focus: Build
Status: Amateur
Yeah this finish is definitely some hardcore stuff. I was reluctant at first but have now decided to strip it all off and re-spray. Unfortunately that means I'll probably have to remove the bridge too in order to get a half decent finish on.

Anyway I installed the inserts and got the neck/body joint about as tight as I'm going to. Took a little while especially since the neck had a slight angle towards the bass end, but I finally got it worked out. The new neck angle in relation to the bridge looks good and it's nice and straight.

So my next question is.....I'll have to make a shim to fill the gap between the fretboard extension and body. I'm wondering if I should glue this shim down between the two? I feel like the bolt on neck without any sort of tenon joint is going to be inherently weak. I know the advantage of bolt on neck is so they can be removed easily, but once it's done I don't feel like it should need another reset for a LONG time. I can glue the neck joint as well but there's very little 'meat' there to glue, and it's end grain anyway. By gluing the fret board extension down I feel it may give me some of the rigidity it's lacking?

I tried to load some photo's but photo bucket is not working for me tonight.....oh the non-stop video ads all work great on their end, but can't upload a couple photos:>(

Jeff


Top
 Profile  
 
PostPosted: Thu Jan 21, 2016 9:47 pm 
Offline
Walnut
Walnut

Joined: Mon Dec 14, 2015 9:35 pm
Posts: 24
First name: Jeff
Last Name: Duncan
City: Concord
State: Ma.
Zip/Postal Code: 01742
Country: USA
Focus: Build
Status: Amateur
Ok let me try again....inserts
Image
top side of joint, (pencil marks were to remind me which side needed attention to get neck straight.
Image
and bottom of joint...you can see most of the shim has been removed through sanding to fit....
Image


Top
 Profile  
 
PostPosted: Thu Jan 21, 2016 10:05 pm 
Offline
Walnut
Walnut

Joined: Mon Dec 14, 2015 9:35 pm
Posts: 24
First name: Jeff
Last Name: Duncan
City: Concord
State: Ma.
Zip/Postal Code: 01742
Country: USA
Focus: Build
Status: Amateur
Not a great pic, but tried to show the gap where I need a shim between body and fret board....
Image


Top
 Profile  
 
PostPosted: Fri Jan 22, 2016 12:47 am 
Offline
Cocobolo
Cocobolo
User avatar

Joined: Mon Dec 28, 2015 10:15 pm
Posts: 110
Location: South Bend IN U.S.A.
First name: Bob
Last Name: English
City: South Bend
State: IN
Country: U.S.A.
Focus: Build
Status: Professional
You are right about gluing it anyway, as you may never need a neck reset again, and the instrument should have settled by now. The threaded inserts will serve as clamps. Bolt on necks without an actual neck socket like some fender and Eppiphone's have, have the fingerboard glued down, with the small exception of some jazz arch tops that have room for a reinforced fingerboard extension. Also bolt's in the heel, are more for alignment in manufacturing situations, and not for easy removal, as they get glued too. Shimming the fingerboard will not hurt, it's not a major resonant zone there, and you can use all the strength you can get.

_________________
If what you see is what you get, then Stevie Wonder ain't got nothin'!


Top
 Profile  
 
PostPosted: Fri Jan 22, 2016 2:29 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Fri Aug 26, 2011 2:21 am
Posts: 668
Location: Philadelphia
First name: Michael
Last Name: Shaw
City: Philadelphia
State: PA
Zip/Postal Code: 19125
Country: USA
Focus: Repair
Status: Semi-pro
The dowel is to reinforce the neck heel from breakage. Many have done something similar and some still do.

Sent from my HTC Desire 626s using Tapatalk

_________________
Another day, another dollar.


Top
 Profile  
 
PostPosted: Fri Jan 22, 2016 3:31 pm 
Offline
Walnut
Walnut

Joined: Mon Dec 14, 2015 9:35 pm
Posts: 24
First name: Jeff
Last Name: Duncan
City: Concord
State: Ma.
Zip/Postal Code: 01742
Country: USA
Focus: Build
Status: Amateur
Great, thanks for the confirmation on glue. I'll definitely be shimming the finger board as it's even higher than it looks in the pic....probably a solid 1/8" at the opening. But first....more sanding to try and remove that crazy finish.

Jeff


Top
 Profile  
 
PostPosted: Sun Sep 17, 2017 6:21 pm 
Offline
Walnut
Walnut

Joined: Tue Sep 18, 2012 8:22 am
Posts: 1
First name: Dave
Last Name: Fengler
City: Wallingford
State: Connecticut
Zip/Postal Code: 06492
Country: United States
Focus: Repair
Status: Amateur
WOW! My first post almost exactly 5 years from when I joined!

I'm sorry for digging up this zombie thread. I just rediscovered this forum.

I’ve written a 15 page guide to resetting the necks on vintage Yamaha FG’s. It lists (in detail) the tools, parts and steps required. Since I have limited experience with neck resets, someone may have a better way than mine, but mine is proven on vintage Yamaha’s. I did extensive research online and picked the brains of a few luthiers before attempting a neck reset. Yamaha FG’s, at least the 5 I’ve taken apart, are not put together with some “Asian Mystery Glue”. They used regular hide glue, but they used too much of it, including gluing the face of the heel to the side of the guitar. And the neck pocket isn’t directly below the 15th fret, it’s 1/8″ to 3/16″ toward the heel.

See this link to my website. http://yamahavintagefg.com/vintage-yamaha-fg-neck-reset-procedure/


Top
 Profile  
 
PostPosted: Mon Sep 18, 2017 9:38 am 
Offline
Koa
Koa

Joined: Thu Feb 12, 2009 10:27 pm
Posts: 1907
Location: South Carolina
First name: John
Last Name: Cox
Focus: Build
Status: Amateur
This definately classifies in the "Labor of Love" category...

I think the saw and neck bolts is a fine option vs condemning these old but cheap instruments to the trash.... So many of these fall in the $100-300 range - and so it's often more "cost effective" to just buy another one.. That's kinda unfortunate - because these Yamaha guitars are among the best in their price class..

A couple tips I would offer folks considering cutting a neck off to do a bolt on conversion reset....

1. Drill alignment holes through the neck block into the neck heel before removing the neck. These will take your bolt hardware. You will need a compact 90 degree drill to accomplish drilling these 2 holes from inside the soundhole. . This ensures the alignment is more or less right on reassembly...

2. Install the bolt hardware and use this to stabilize the neck while "flossing" the neck joint to hit your desired alignment..


Finally - If you are considering replacing the top with a solid spruce/cedar top - this is the time while the neck is already off. I am not 100% sure I would do this to a Yamaha - but I would replace the top on a miscellaneous Asian import.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 18 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group
phpBB customization services by 2by2host.com