Post by CTGull on Sept 28, 2020 20:54:15 GMT -5
This is more or less part 2 of my Vintage Yamaha Neck Reset Procedure.
It’s no secret that vintage Yamaha Neck Resets can be difficult, for a few reasons. The neck pocket is not below the 15th fret; the dovetail joint is tight; they used lots of glue; and many times they not only glued the dovetail joint, they glued the heel to the side of the guitar. And something else that is rarely talked about; hide glue doesn’t soften much by heat only, it needs moisture. If the steam can’t get to areas that need it, it will not release. If the area releases (with a lot of force), typically it's because the wood sheared.
That’s also the problem when releasing the fretboard from the top. You need to heat the fretboard enough to soften the glue, without loosening anything else. And it doesn’t soften much, sometimes just enough for you to feel the spatula pushing in when wiggling it, moving a little faster than if it was digging into the wood. Another problem is typically the rosette is sticking up slightly. This stops the spatula. Once you get by it (many times over it) the fretboard is lifting at a higher angle than it should be at that point. Once the spatula has passed the rosette it is pushed down by the fretboard, typically causing it to dig into the top. This happens a lot! This causes another problem. If the spatula has dug into the top it can look like the fretboard is separated, but that strip of wood is still connected to the top at the 14th/15th fret area. That will make removing the neck more difficult. You may feel or hear the spatula dig into the wood, but you won’t know how bad it is until the neck is off. You can probe from the side, but more than likely it to will dive down into the top when it hits anything that is stuck to the bottom of the fretboard. This is made worse by the top being plywood, the wood tends to separate at the ply glue joint.
Getting the neck to release can be very difficult. You have no idea what’s in there before you start. All you can do are the normal steps, steam, wiggle, pressure, repeat. You want the wiggling to open up areas slightly for the steam to get into, to further soften the glue farther down into the joint. But if the dovetail is tight and you can’t get any movement by wiggling, even after 6 minutes of steam, try going 1 or 2 minutes longer. If there’s still no change turn off the steam, remove the guitar from the neck jig, and cut into the heel corners area deeper, 1/8” or more. If there’s no wiggling after 6 minutes the heel is probably glued to the side of the guitar. Cutting in the heel corner can help release some of that. Worst case, some of the side is torn off and is stuck to the heel when the joint finally releases.
Also, the heel to neck lamination can crack or separate from the combination of heat, moisture, and wiggling. Yes, the wiggling that you desperately need is also your enemy. Too much heat, moisture and wiggling will crack and eventually separate the heel/neck lamination. This is why I normally stop after 6 minutes of steaming to re-evaluate the heel corners. Once the heel/neck lamination fails your only choice is to separate the neck from the heel and attempt to remove the heel that is still stuck in the guitar. You’ll notice there is a large slotted dowel stuck in the heel. This helps keep the neck together if the heel breaks. The slot is for the truss rod. And it will help you line up the heel to the neck once you get the heel out of the guitar.
The heel lamination has separated. You can see excess glue that was holding the neck to the side of the guitar.
As bad as it looks, all is not lost! The heel can be removed (with difficulty) from the guitar and glued back to the neck. You have to drill holes in the dovetail joint and the corners of the heel, to inject more steam and heat to attempt to soften the glue holding the heel in. You’re going to need a long 3/32” drill bit, the same size you used for the steam holes in the fretboard. A normal length drill bit won’t drill far before the drill chuck hits the guitar top. First, release the pressure of the neck jig that is pushing on the heel. Then drill a parallel hole into both dovetail joints, being sure you maintain the parallel angle. And drill holes into the corner of the heel, keeping the drill parallel to the heel. Try to make the holes about 1-1/2” deep. You’ll probably have to clean the flutes of the drill a few times and it gets clogged with soft wood and glue. Alternate steaming in the 4 holes for 6 to 10 minutes, wiping up any water that's running out of the heel. Then shut off the steam, remove the steam tip, and start cranking on the neck jig heel pusher screw. I do this after because keeping the high pressure on the heel during the whole process can cause the heel to distort from the heat and moisture. The heel isn’t going anywhere until after the moisture has had time to seep into the joints. Crank on the screw as much as you feel comfortable, then go a little more. This is your last chance to get the heel out. If it doesn’t pop immediately, all is not lost. Let it sit for a few minutes, but not with your face anywhere near it. In my 2 successful uses of this technique, the heel has popped a minute or 2 after giving up. Once with a lot of force, it hit the ceiling. It wouldn’t hurt to place a towel over the area to slow it down if it does explode out of the pocket.
Drill (4) holes in the corners of the dovetail.
Add more steam! A LOT of steam!! You've got nothing to lose here. This is the last effort to get the heel out.
Once the heel is out you’ll probably be looking at a lot of glue on all surfaces. Scrape all the glue off while it’s still soft and wet. But be careful not to damage the heel lamination surfaces or edges. Then let the 2 parts dry for a day or 2.
LOTS of glue was holding the face of the heel to the side of the guitar.
This is probably the worst I've seen.
If any of the top is stuck to the bottom of the fretboard after the neck has been removed, scrape it off the bottom of the fretboard ASAP while the glue is still soft, and glue and clamp it back to the top. Be sure to realign or remove any out of place strings of wood that will prevent proper placement of the piece(s) to be reglued. This is MUCH easier to do now vs. wait until after everything has dried.
Some of the top is stuck to the bottom of the fretboard.
Clean up/remove all the loose fibers.
Glue & clamps the pieces back to the top ASAP.
After.
It’s possible the dowel won’t fit back in the hole. I’ve found the head of the truss rod may have compressed the wood and pushed some into the dowel hole. You’ll have to sand a little off of the dowel to make it fit. You can’t drill it out because there are a couple of pieces of wood in there, a truss rod channel filler strip against the fretboard, and a short piece supporting the truss rod, and the dowel goes all the way to the fretboard.
I sanded some of the dowel to get it to fit back in the hole.
Once you get the dowel to fit in the hole and the 2 parts lined up, use wood glue to glue them together. Wipe a small amount of glue on the dowel, but DON’T put glue in the dowel hole! You don’t want glue to get into the truss rod channel. BUT!! Figure out how you’re going to clamp it first and practice. I use the Stew Mac guitar vise. You’ll need to quickly clamp the parts together and in location before the glue starts to set. Not clamping enough will result in a larger than necessary gap. Clean up any glue squeeze out with a wet paper towel.
Clamped in the Stew Mac guitar vise.
Glue squeeze out all around.
Glue squeeze out cleaned up.
While the wood glue is probably enough to hold the heel together, I go one step further, although it is risky and requires some special drill bits. I add (2) 3/16” hardwood dowels (glued in with epoxy) from the inside to reinforce it, but you’ll need longer drill bits. On both sides in the corner of the dovetail, starting about 3/4” from the heel crack, drill a 1/8” hole on a compound angle to not break out the side of the heel. The smaller drill allows you to get deeper into the corner of the dovetail. Drill carefully to get it about ¾” past the heel lamination but not break thru the fretboard. You may break into the truss rod channel, if you feel the drill hit something solid stop quickly. Then open up the holes with a long 5/32”, then 13/64” drill. This is 1/64” larger than the dowel to have a place for the epoxy to go. Be sure to use hardwood dowel, it has more tensile strength than softwood. Once you think your holes are to the right depth, stick a piece of dowel in it, mark where it exits the hole, pull it out, and see where it actually ends. Drill deeper if necessary and check again. Cut the dowel off just short of that line. Do the same for the other hole, keeping the dowels separate because they probably won’t be the same length. If your holes hit the truss rod channel you’ll need to remove the truss rod and partially plug the hole. Loosen the truss rod nut until it is disengaged, then push on it to force the truss rod inward. This will be difficult because they used grease in the truss rod channel (probably to reduce the chance of rattling), which has dried up. After pushing the truss rod nut in as far as it will go, remove the nut, pry on the head of the truss rod, and remove it. Then you will need to partially plug it to prevent all your epoxy from ending up in there!! I put oil or grease on a #9 (.196”) long drill, but anything that fills the truss rod channel snuggly and goes slightly past the holes will work. Put painters tape on the heel and dovetail surfaces you don’t want epoxy on (all!). Mix up some epoxy and half fill the hole. Or just guess, just don’t put too much or too little. I use a popsicle stick to mix and put the epoxy in the hole, but I cut shallow angles in the tip allow better control of where the epoxy is getting dropped. Push the dowels into the epoxy filled holes until they are flush with the heel. Clean up any epoxy squeeze out quickly. Once the dowels are in, let the epoxy set for about 5-10 minutes and pull the plug out of the truss rod channel. Clean it with denatured alcohol to remove the epoxy, then reinsert it. Do this every few minutes until you don’t see epoxy flowing into the truss rod channel. This will prevent a flood of epoxy into the channel, BUT you will still need to clean it out by using a long 13/64” drill after the epoxy has set. After the epoxy has set for a day I use a 1/8” ball burr bit in the Dremel to remove the excess dowel or epoxy from the dovetail & heel area.
Drill compound angle holes.
5/32" drill.
13/64" drill.
Mix the epoxy.
Cover everything you don't want to risk dripping epoxy onto.
Push the dowels in.
Cleaned up later with the Dremel & 1/8" burr bit.
If you are successful removing, reattaching, and reinforcing the broken heel it may not be pretty, but it will be strong and another vintage FG will be saved. Now move on to the fun neck reset to finish the job. No one said saving these old FG’s was going to be easy!!
It’s no secret that vintage Yamaha Neck Resets can be difficult, for a few reasons. The neck pocket is not below the 15th fret; the dovetail joint is tight; they used lots of glue; and many times they not only glued the dovetail joint, they glued the heel to the side of the guitar. And something else that is rarely talked about; hide glue doesn’t soften much by heat only, it needs moisture. If the steam can’t get to areas that need it, it will not release. If the area releases (with a lot of force), typically it's because the wood sheared.
That’s also the problem when releasing the fretboard from the top. You need to heat the fretboard enough to soften the glue, without loosening anything else. And it doesn’t soften much, sometimes just enough for you to feel the spatula pushing in when wiggling it, moving a little faster than if it was digging into the wood. Another problem is typically the rosette is sticking up slightly. This stops the spatula. Once you get by it (many times over it) the fretboard is lifting at a higher angle than it should be at that point. Once the spatula has passed the rosette it is pushed down by the fretboard, typically causing it to dig into the top. This happens a lot! This causes another problem. If the spatula has dug into the top it can look like the fretboard is separated, but that strip of wood is still connected to the top at the 14th/15th fret area. That will make removing the neck more difficult. You may feel or hear the spatula dig into the wood, but you won’t know how bad it is until the neck is off. You can probe from the side, but more than likely it to will dive down into the top when it hits anything that is stuck to the bottom of the fretboard. This is made worse by the top being plywood, the wood tends to separate at the ply glue joint.
Getting the neck to release can be very difficult. You have no idea what’s in there before you start. All you can do are the normal steps, steam, wiggle, pressure, repeat. You want the wiggling to open up areas slightly for the steam to get into, to further soften the glue farther down into the joint. But if the dovetail is tight and you can’t get any movement by wiggling, even after 6 minutes of steam, try going 1 or 2 minutes longer. If there’s still no change turn off the steam, remove the guitar from the neck jig, and cut into the heel corners area deeper, 1/8” or more. If there’s no wiggling after 6 minutes the heel is probably glued to the side of the guitar. Cutting in the heel corner can help release some of that. Worst case, some of the side is torn off and is stuck to the heel when the joint finally releases.
Also, the heel to neck lamination can crack or separate from the combination of heat, moisture, and wiggling. Yes, the wiggling that you desperately need is also your enemy. Too much heat, moisture and wiggling will crack and eventually separate the heel/neck lamination. This is why I normally stop after 6 minutes of steaming to re-evaluate the heel corners. Once the heel/neck lamination fails your only choice is to separate the neck from the heel and attempt to remove the heel that is still stuck in the guitar. You’ll notice there is a large slotted dowel stuck in the heel. This helps keep the neck together if the heel breaks. The slot is for the truss rod. And it will help you line up the heel to the neck once you get the heel out of the guitar.
The heel lamination has separated. You can see excess glue that was holding the neck to the side of the guitar.
As bad as it looks, all is not lost! The heel can be removed (with difficulty) from the guitar and glued back to the neck. You have to drill holes in the dovetail joint and the corners of the heel, to inject more steam and heat to attempt to soften the glue holding the heel in. You’re going to need a long 3/32” drill bit, the same size you used for the steam holes in the fretboard. A normal length drill bit won’t drill far before the drill chuck hits the guitar top. First, release the pressure of the neck jig that is pushing on the heel. Then drill a parallel hole into both dovetail joints, being sure you maintain the parallel angle. And drill holes into the corner of the heel, keeping the drill parallel to the heel. Try to make the holes about 1-1/2” deep. You’ll probably have to clean the flutes of the drill a few times and it gets clogged with soft wood and glue. Alternate steaming in the 4 holes for 6 to 10 minutes, wiping up any water that's running out of the heel. Then shut off the steam, remove the steam tip, and start cranking on the neck jig heel pusher screw. I do this after because keeping the high pressure on the heel during the whole process can cause the heel to distort from the heat and moisture. The heel isn’t going anywhere until after the moisture has had time to seep into the joints. Crank on the screw as much as you feel comfortable, then go a little more. This is your last chance to get the heel out. If it doesn’t pop immediately, all is not lost. Let it sit for a few minutes, but not with your face anywhere near it. In my 2 successful uses of this technique, the heel has popped a minute or 2 after giving up. Once with a lot of force, it hit the ceiling. It wouldn’t hurt to place a towel over the area to slow it down if it does explode out of the pocket.
Drill (4) holes in the corners of the dovetail.
Add more steam! A LOT of steam!! You've got nothing to lose here. This is the last effort to get the heel out.
Once the heel is out you’ll probably be looking at a lot of glue on all surfaces. Scrape all the glue off while it’s still soft and wet. But be careful not to damage the heel lamination surfaces or edges. Then let the 2 parts dry for a day or 2.
LOTS of glue was holding the face of the heel to the side of the guitar.
This is probably the worst I've seen.
If any of the top is stuck to the bottom of the fretboard after the neck has been removed, scrape it off the bottom of the fretboard ASAP while the glue is still soft, and glue and clamp it back to the top. Be sure to realign or remove any out of place strings of wood that will prevent proper placement of the piece(s) to be reglued. This is MUCH easier to do now vs. wait until after everything has dried.
Some of the top is stuck to the bottom of the fretboard.
Clean up/remove all the loose fibers.
Glue & clamps the pieces back to the top ASAP.
After.
It’s possible the dowel won’t fit back in the hole. I’ve found the head of the truss rod may have compressed the wood and pushed some into the dowel hole. You’ll have to sand a little off of the dowel to make it fit. You can’t drill it out because there are a couple of pieces of wood in there, a truss rod channel filler strip against the fretboard, and a short piece supporting the truss rod, and the dowel goes all the way to the fretboard.
I sanded some of the dowel to get it to fit back in the hole.
Once you get the dowel to fit in the hole and the 2 parts lined up, use wood glue to glue them together. Wipe a small amount of glue on the dowel, but DON’T put glue in the dowel hole! You don’t want glue to get into the truss rod channel. BUT!! Figure out how you’re going to clamp it first and practice. I use the Stew Mac guitar vise. You’ll need to quickly clamp the parts together and in location before the glue starts to set. Not clamping enough will result in a larger than necessary gap. Clean up any glue squeeze out with a wet paper towel.
Clamped in the Stew Mac guitar vise.
Glue squeeze out all around.
Glue squeeze out cleaned up.
While the wood glue is probably enough to hold the heel together, I go one step further, although it is risky and requires some special drill bits. I add (2) 3/16” hardwood dowels (glued in with epoxy) from the inside to reinforce it, but you’ll need longer drill bits. On both sides in the corner of the dovetail, starting about 3/4” from the heel crack, drill a 1/8” hole on a compound angle to not break out the side of the heel. The smaller drill allows you to get deeper into the corner of the dovetail. Drill carefully to get it about ¾” past the heel lamination but not break thru the fretboard. You may break into the truss rod channel, if you feel the drill hit something solid stop quickly. Then open up the holes with a long 5/32”, then 13/64” drill. This is 1/64” larger than the dowel to have a place for the epoxy to go. Be sure to use hardwood dowel, it has more tensile strength than softwood. Once you think your holes are to the right depth, stick a piece of dowel in it, mark where it exits the hole, pull it out, and see where it actually ends. Drill deeper if necessary and check again. Cut the dowel off just short of that line. Do the same for the other hole, keeping the dowels separate because they probably won’t be the same length. If your holes hit the truss rod channel you’ll need to remove the truss rod and partially plug the hole. Loosen the truss rod nut until it is disengaged, then push on it to force the truss rod inward. This will be difficult because they used grease in the truss rod channel (probably to reduce the chance of rattling), which has dried up. After pushing the truss rod nut in as far as it will go, remove the nut, pry on the head of the truss rod, and remove it. Then you will need to partially plug it to prevent all your epoxy from ending up in there!! I put oil or grease on a #9 (.196”) long drill, but anything that fills the truss rod channel snuggly and goes slightly past the holes will work. Put painters tape on the heel and dovetail surfaces you don’t want epoxy on (all!). Mix up some epoxy and half fill the hole. Or just guess, just don’t put too much or too little. I use a popsicle stick to mix and put the epoxy in the hole, but I cut shallow angles in the tip allow better control of where the epoxy is getting dropped. Push the dowels into the epoxy filled holes until they are flush with the heel. Clean up any epoxy squeeze out quickly. Once the dowels are in, let the epoxy set for about 5-10 minutes and pull the plug out of the truss rod channel. Clean it with denatured alcohol to remove the epoxy, then reinsert it. Do this every few minutes until you don’t see epoxy flowing into the truss rod channel. This will prevent a flood of epoxy into the channel, BUT you will still need to clean it out by using a long 13/64” drill after the epoxy has set. After the epoxy has set for a day I use a 1/8” ball burr bit in the Dremel to remove the excess dowel or epoxy from the dovetail & heel area.
Drill compound angle holes.
5/32" drill.
13/64" drill.
Mix the epoxy.
Cover everything you don't want to risk dripping epoxy onto.
Push the dowels in.
Cleaned up later with the Dremel & 1/8" burr bit.
If you are successful removing, reattaching, and reinforcing the broken heel it may not be pretty, but it will be strong and another vintage FG will be saved. Now move on to the fun neck reset to finish the job. No one said saving these old FG’s was going to be easy!!
