Emerald Ash Borer Build

[guitarbuilder]

My only experience with drying wood was getting a fantastic piece of "green" curly maple that was given to me in a huge plank form. It was painted on the ends. I brought it into my apt at the time. At some point I cut into it and it just closed up on the saw. Now just this week I just bought some 8/4 poplar milled locally. He cut and stickered it last year. He said he used a dehumidfiing kiln on it and it is currently at 13 percent. I won't use it for a year or so, trying to stick to the 1 year per inch rule. If I were you, I'd do the oven dry method to determine where you are now.

Along the same line, I bought some resawn flatsawn "thin wood" timbers that arrived flat, and are now so cupped I won't use them on anything important. Sawing and drying is pretty critical to end up with what you want I guess.

 

[Freeman Keller]

Chaos, I know nothing about drying wood, its supposed to be dry when I buy it and I store all my wood at 40% RH until I'm ready to use it, which in some cases is several years.

However I figure Ken Warmoth knows a bit about drying wood for use in guitar bodies and necks and I often quote from an interview with him in one of the lutherie magazines. He describes the small "low temperature" kiln that they use to dry all their wood. I don't totally understand the process but he says that it takes 4/4 stuff about 30 days to dry to 6.5% MC, body wood about 45.

His kiln is home made and consists of a refrigeration unit, a heater and a fan in a sealed box, with some control stuff. As water is removed from the wood it condenses as frost on the coils. When the condenser shuts off the frost melts and runs into a pan where he collects and measures it. He says what he is looking for is when it stops extracting water. He starts at 30C (86F) in the summer, runs until it stops extracting water, bumps the temperature up 5C, and keeps going up until he gets to 45C (114F), at which point when no more water comes out its 6.5% MC. He runs the fan for a week to try to equalize the MC, then takes the wood out and lets it stabilize in the shop. He says he likes to wait at least 6 months before using the wood, a year is better.

 

[Jim_in_PA]

I've been air drying wood for years, but will certainly not represent myself as an "expert", however. That said, the challenge with thicker material like this is that you can get a relatively rapid drop in surface moisture and below that surface while the core of the stick is still "working". An 8/4 slab, even with proper ventilation, etc., can still take quite a while to get where it needs to be evenly through the wood so that it all is at ambient MC. My solution has always been time...measured in years.

I'm glad you're reading the Hoadly book, regardless of edition. It's considered the "bible" of everything about wood, even after all these years. I met him quite a while ago. Nice fellow.

 

[Freeman Keller]

I'm glad you're reading the Hoadly book, regardless of edition. It's considered the "bible" of everything about wood, even after all these years. I met him quite a while ago. Nice fellow.

Warmoth mentions the Hoadly book too

 

[Jim_in_PA]

Yea, he's considered one of the most important authorities on the subject. I think I had the second edition of his book, but sold it along with a lot of other books prior to moving.

 

[chaosman12]

... and I had forgotten how nice it is to learn from a book. Everything is thoughtfully laid out by humans; large and clear, no scrolling, no zooming, no clicking, no ads!

 

[chaosman12]

Short recap: This stack of wood has been drying for about 10 months in my basement. I've been weighing it every week or so, and the weight loss has slowed to a crawl. Implying that the moisture loss has has slowed, or even stopped.

I have a $30 pin type moisture meter and the surface moisture content (MC) measured from 6.5 to 7.

However, to figure out if the wood is "dry enough", I need to measure the moisture content at the center of the wood. So I ripped one of the boards lengthwise and measured the MC along the fresh cut edge. The MC readings ranged from the high 8's to low 9's.

So, is 9% MC dry enough? Time to get nerdy.

Wood responds to the air humidity around it. As the air gets more humid, the wood will absorb water and then expand (and vice versa). If the humidity stays constant for a long time, the moisture in the wood will eventually stop changing at which point the wood's MC has reached its "equilibrium moisture content" (EMC). In other words, the MC in the wood is in equilibrium with the ambient air RH. If the air humidity doesn't change, the MC in the wood won't change either.

This chart (from wikipedia) shows what the EMC is for any given air humidity. The 32F and 86F curves are close to each other so temperature in that range doesn't have much effect on the EMC.

The RH in my basement is around 50%. Looking at the chart, at a 50% RH, the equilibrium MC in the wood is about 9%. Which is right in the ballpark of what I measured at the center of the board I ripped down the middle.

Is the wood dry enough? The weight of the wood has stopped changing, and the MC in one of the boards is pretty close to the EMC for my basement RH, which leads me to think that this wood is ready to start working with.

 

[chaosman12]

So here are the 4 pieces I have to work with.

I made a "negative" template of the guitar shape to help visualize some options below using the two widest pieces.

Option 1 is a nice clean look. Brings in a little of the darker wood (heart wood?) on the lower horn for interest. Note: When I trim the right hand piece to create a glue edge, I'd remove the two small defects,

Option 2 has some of the darker wood in the arm relief area:

Option 3: The darker wood makes a peninsula. I like the penisula look, but I don't like that there would be a hard edge where the dark and light boards meet:

Option 4: I had an idea to "celebrate" the split and fill it with epoxy to stabilize it. Maybe mix some emerald green glitter into clear epoxy.

My main concern is that even if the epoxy stabilizes the crack, it's from the center of the tree, which in general is the least stabile. So having the neck and bridge mounted on the least stabile part might be is risky. Like building a nuclear power plant on a known fault line then naming it after the devil.

Any opinions on the above options?

 

[TheZ]

I would avoid having the crack in the middle like that. Maybe just rip that board down the middle and use it as the two outside pieces for a narrower middle piece?

 

[guitarbuilder]

I'd get rid of the cracks by ripping and jointing those pieces. I'd alternate the rings on each piece too during glue up.

 

[old wrench]

... and I had forgotten how nice it is to learn from a book. Everything is thoughtfully laid out by humans; large and clear, no scrolling, no zooming, no clicking, no ads!

Amen !!!

I would have a hard time getting by without books

.

 

[chaosman12]

I need a little sanity check:

I routed a neck pocket in some scrap using the template and router settings I intend to use on the real body. I've read many times here (I hear you Freeman) about the fret plane being level with the bridge at the bridges lowest position.

I started with a .63" (about 5/8") deep pocket which seems to be the recommended depth with a 1" neck. My neck is 1" at the center including the frets.

However, the fret plane is still a good 0.1" above the saddle (at the point where the string hits):

Would you say that the neck pocket simply needs to be deeper by about 0.1"? Would a neck pocket 0.73" deep be highly unusual?

For educational purposes, I'm wondering why it needs to be deepened. Is my neck thicker than normal?

Or maybe the saddle at its lowest is lower than most saddles?

I've check the fret plane and it is parallel to the body.

**** EDIT - Updated the drawing ****
The sketch below summarizes the situation. The minimum height of the saddle is 0.313". and the fret plane is 0.405" above the body. Thus the fret plane is .405-0.313=0.092" above the minimum height of the saddle

**** END EDIT ****

Here's pics of the neck set into the scrap wood.

Thanks for your help as always.

 

[guitarbuilder]

You want 3/8" of neck sticking up. A 1" thick heel top to bottom( not counting frets) in a 5/8" deep neck cavity.... Rout your neck cavity down until you have 3/8" of wood sticking up. Get an accurate measuring device too. Make sure your neck cavity is the same depth and that it is parallel with your top.... These are the normal specs for a traditional Tele bridge.


It looks like you are including fret height in your sketch... That would be more than 1" and that's probably where the error is.

 

[chaosman12]

Thanks GB. I double checked all my measurements, and also verified that the pocket bottom and the fret plane are parallel to the body. Note that I also updated the sketch to show the actual dimensions. The old sketch was what I wanted the fret plane to be.

You want 3/8" of neck sticking up.

The last picture in my post, the blurry one, shows that the fretboard is about 3/8". Maybe a tad less.

It looks like you are including fret height in your sketch... That would be more than 1" and that's probably where the error is.

I remeasured with digital calipers, and the thickness, including the fret at the center of the last fret, is 1.02".

I'm probably measuring or doing something stupid. However, it doesn't usually take me so long to figure out where I'm screwing up!

 

[chaosman12]

I'll fine tune the neck pocket depth when I rout it on the real body.

Now it's time to turn the planks into a body. I decided to "celebrate" some of the defects of the wood from my back yard tree. I have to give some credit to my artistic daughter who liked the idea and helped to achieve a pleasing integration of the defects and other guitar parts.

I intend to fill the defects with epoxy colored with green mica powder to produce a shimmery effect. I will do a lot of experimenting however and will go with a plan B if it doesn't look right.

The above mock up uses two boards. In the picture below, you can see that the boards have some serious warpage. The cardboard strip represent the 1.65" flat board I need to get from this bent mess. At 40 lbs/ft3, this wood is pretty dense so the final body will be as thin as possible. Right now I just want to get the two sides flat and parallel for the glue up. I'll plane it down to final thickness after the glue up.

I have a planer, but no jointer. While I could hand plane one side level, I recently discovered this flattening technique using a thickness planer with a carrier board.

The carrier board is piece of MDF the max width of the planer (13") and longer than the stock being flattened. There's a low cleat at the in-feed end. I rock the warped board back and forth to be about level, then insert tapered shims to stabilize it.

A few dabs of hot glue on the shims and where the slab touches the carrier holds everything in place:

Ready to feed into the planer:

I made pencil lines on the top so I can see what's getting planed off. As expected the first pass is getting the high corners. So everything is holding.

I continue to pass it through the planer until all the pencil lines are gone, which means that face is flat.

I then pop it off the carrier board with a stiff putty knife because the board can now be fed with the flat side down:

I ripped flat square edges on the two boards using my table saw with a Freud thin kerf rip blade (24 tooth?). I have a 70's era contractors saw, so thick hardwood like this would be a big problem even with a good quality multi-purpose blade (like a Forrest WWII). This Freud rip blade easily rips through the ash with very minor saw marks or burning. It leaves a glue ready joint. Can't recommend it enough.

Glue makes the edges slippery, so to keep the boards from slipping under clamping pressure, I put in three biscuits. I don't have a biscuit cutter so I use a slot cutter bit in my router. The layers of green tape are to fine tune the depth of the slot:

I plunge the router into the edge of the board and sweep it left and right stopping when the center line of the biscuit is at the two red marks on the router base:

The glue up.
Biscuits eliminate slippage and make the glue up much less frantic. Also making it easier are these Bessey "K" clamps which I've owned for several decades. They were expensive - but worth it because the jaws stay perfectly parallel. A K clamp is in the category of tears when you buy it, and smiling every time you use it.

 

[chaosman12]

Routing the neck pocket.

I ran the glued up body through the planer until the top and bottom were perfectly smooth, and then sketched out the approximate location of the bridge, neck and pickups. I really wanted to cut out the body to see and feel a guitar emerge, but I think it is best to keep as much wood around as possible. So I only trimmed down to the neck pocket.

I created a template of the neck heel on 1/4" hardboard (aka Masonite). I started by tracing the shape onto the hardboard

Then cutting it out with a jigsaw and refining the shape down to the pencil line. Gluing sandpaper to sticks of wood and dowels is a great way to make custom wood shaping tools for a specific task.

I went real slow up to the pencil line checking the fit many many times. As I approached the line it seemed like I was checking the fit after every stroke of the sandpaper. The fit is neither tight or loose (if that makes any sense).

A proper neck pocket is the starting point for good geometry. I have a lot of time invested in this body blank, so nerves were high and I forgot to take photos of the routing process. I was particularly concerned with keeping the centerline of the pocket close to the centerline of the guitar. Suffice it to say, I used plenty of double sided tape!

Based on tests on scrap, I made the pocket depth 0.7".

Fit from the top looks good.

And from below:

I measured the height of the fret plane at the neck and at the bridge to check that the fret plane is parallel to the body.

Height at the neck:

... and fret plane height at the bridge location. Both a bit more than 5/16". I think this is sufficiently parallel.

With the saddle at the lowest position there is some space.

Too much space?

The height of the fret plane is a bit more than 5/16" (call it about 0.33") above the body. The max height of the bridge (without getting longer screws) is 0.46".

This means that the saddle at max height raises the string another 0.13" above the current fret plane height (0.46" - 0.33"). At the 12th fret, the string height increase would be 0.065". (The 12th fret is halfway to the nut, so the string height at the 12th moves half as much as at the bridge.) Note, these measurements are all at the center line.

I think I'm in the ball park, and will move on and install the neck bolts.

 

[chaosman12]

I am going to secure the neck to the body with bolts, ferrules and threaded inserts.

Start the layout by transferring the next pocket shape to the back of the body

After laying out the bolt locations, I drilled the countersink for the ferrules with a Forstner bit. I intend to do some rounding of the body in this neck area, and may even plane the body down a bit to make it thinner. So at this point I just want to establish the bolt hole location perfectly centered in the countersink. I'll come back later to drill the countersink to its final depth. But in the meantime, I now know where to drill the hole.

With the neck in the neck pocket, I will flip it over and drill through the body into the neck to ensure the bolt holes in the body line up with the holes for the threaded inserts. To hold the neck in place when the body is flipped over, the neck is held in the pocket with a piece of wood screwed placed across the neck and secured to the body blank with two screws as shown below. The neck and pocket are a nice piston fit, and this bracing arrangement holds the neck very securely.

When the body is flipped over on to the drill press table, these two 2x4 scraps provide a stable base.

Set the depth stop. The hole needs to be deep enough for the threaded insert, plus about 0.2" to allow for a bolt to extend past the threaded insert (better to overshoot, than to undershoot the length of the bolt).

I recently saw someone had drilled clean through the neck and out the fret board. I have small low budget drill press and the depth stop has been known to come loose, so I check it often...

I drilled the first three holes using a 3/16" drill bit which is just a bit wider than a #8 bolts.

I haven't decided where the fourth bolt should go, so I will finish installing the 3 threaded inserts, reassemble and pick a spot for the 4th bolt. Then repeat the above procedure.

 

[chaosman12]

In the previous post, I drilled 3/16" hole through the body into the neck. I'll now widen the 3/16" hole in the neck to 17/64" to accommodate the threaded insert. As mentioned earlier the hole depth is set by the height of the threaded insert plus some spare room below the insert. In this case that a little over 1/2".

I rest a small square next to the hole, so I can keep the bit perpendicular to the surface by keeping the bit parallel to the square.

Since I'm chasing an existing hole, the bit will easily follow that hole, so no need to use a drill press. To prevent tear out, I run the drill in reverse for a few revolutions to chamfer the entry hole. Also, don't use much downward pressure otherwise the drill bit can catch the wood and unexpectedly suck itself into the hole. This can cause you to loose control and/or lead to some splintering.

The inserts came with an installation tool which I tried on a few scraps. I found it difficult to keep the insert straight. The tool was a staight shaft that went through the insert and it had two little tabs to engage the slots in the top of the insert. The problem was that it was a sloppy fit which made it difficult to "steer" the insert to keep it straight as you are threading it into the wood. Also, the tabs could slip and bugger up the slots on the insert.

I can see why most people make something from a bolt and a few nuts. I used two nuts and a split washer so I could get the flats of one nut offset from the other. This allow the first nut to to slip into a socket, and the second nut rest against the edge of the socket keeping everything straight.

Then it all gets epoxied together with some good 'ol JB Weld (that stuff is good).

I use it with a handle with a hex head socket for screw bits:

I'm using the fixture that I used to hold the neck for carving, to drill the holes and drive in the inserts:

When driving the insert use a lot of downward force while trying to keep the socket (and thus the insert) straight. Turn it a 1/4 of a turn then check the socket for square in two directions. Using this driver, you can easily make course corrections by applying slight pressure to and fro, left and right if it seems to not be going in straight.

I totally forgot to take some pics of installing the insert. Probably because I was focused/obsessed on driving them in straight. Anyway, it seemed to pay off because everything lined up well and easily screwed together.

 

[chaosman12]

Locating the bridge is probably one of the more frequently asked questions here on TDPRI. And for good reasons. The bridge must be positioned with relationship to the neck in the X, Y and Z directions. If you screw it up, strings could be too close to the edge of the fretboard, you may not be able to adjust the action to your preferred height, and your guitar may play out of tune as you play up the neck (intonation).

First, I read the two posts below. Both are TDPRI classics.
The first post is detailed step by step instructions with great pictures:

<Search for topic: COMPLETED - Guitarbuilder's 2014 Monterey II Guitar>

This second post is more about understanding what you are doing, and how pocket depth, neck angle, bridge position and scale length relate to each other. With understanding its easy to make the adjustments to dial in the precise location.

<Search for topic: Building for playability>

Note, When I include links to the above two posts, I get an error that it can't be used because it may be spam or invalid. Weird, I've included links before with any problems.

The neck is bolted to the body, so here I go.

Since the neck position is fixed, it makes sense that the first step is to extend the neck onto the body with pencil lines. Holding a straight edge to the side of the neck, extend the side of the neck onto the body. Repeat for the other side.

Then extend the neck center line onto the body. Since this is critical, and this is my first build, I did it two ways to check myself. The first way was to mark the center of the 21st and 2nd frets. Align a long straight edge with the two marks and extend it onto the body. The neck is higher than the body, so you need to project the ruler edge down to the body. Alternatively, a flexible straight edge can be flex down to the body.

The second way is to draw lines across the neck edge lines and find the center of those. In the picture below I'm drawing one of those cross lines and shows the already drawn other guide lines.

Measure 25.5 inches (the scale length) from the front of the nut and put a mark on the center line. Then draw a perpendicular line at that point. This line is the theoretical scale length.

I now have all the reference lines I need.

1. On the bridge, I marked the center (between the 3rd and 4th saddles) on the bridge base.

2. I moved the saddles to be almost fully extended, then transferred the point of the saddle that the string touches to the side of the base. This is marked by the EDGE of the brown tape in the pic below.

3. When placing the bridge in relationship to the guidelines:
a) The center of the bridge aligns with the neck center line.
b) The saddle line (tape edge), is placed a little bit behind the 25.5" scale length line. It is set because when you intonate, the saddles will always be moved back (further away from the nut). If you don't address this issue partially at this step, you may not be able to move the saddles back far enough to intonate.

BTW, the drill I'm using in the above pic is called a Vix bit. The end of the bit is shaped like a screw head and fits into the countersink. A hole in the center contains a spring loaded drill bit that drills the pilot hole. It drills a perfectly centered hole every time. I've used it for years on small hinges.

The only way to check your work is to string up the two E strings. Unfortunately, the nut slot in the precut fretboard (sold for a Fender), is too deep for the nut (also sold for a Fender). For now I shimmed the slot with a piece of wood veneer.

I had routed the neck pocket to 0.65". When assembled and strung up, neck stood too high and the saddles could not be adjusted high enough to get the strings off of the frets. The walls of the neck pocket walls were still in place, so it was simple to lower the floor of the pocket to 0.70' using a router.

The action at the 12 th now about 0.08" with the saddle at about mid height. So I think I'm in the ballpark.

String it up yet again and brought it up to pitch. I adjust the truss rod to get the neck flat. The two E string are well aligned with the neck edge and the action is withing range. No string buzz and it intonates!

Whew. Couldn't have done it without the great resources here on TDPRI. Thanks.

 

[chaosman12]

With the neck and bridge located, time to rout for the three single coil pickups. Based on the centerline, I used my handy dandy protractor to make cross lines for each pickup.

I took the locations of each pickup from my friend's strat. The bridge pickup is angled 80 deg from the centerline.

I'm not using a pick guard and I really like the look of pickups mounted from the back that come through a perfectly sized hole. But to keep it simple for my first build (and to move the project along a little faster), I decided to mount the pickups from the front.

I'm going to rout a cavity slightly larger than a pickup cover, then undercut one side to accommodate the shape of the pickup's baseplate.

I made the template out of 1/4" hardboard. I like working with 1/4" hardboard because it is easy to cut and shape, but you do have to be careful when setting the bit depth so that the bearing hits the template.

To start, I drilled the two ends with a Forstner bit:

Then cut between them with a jigsaw, and smoothed it all out with files, and with sandpaper glued to small sticks of wood.

I don't spare the double stick tape. I've read several accounts on TDPRI of DS tape slipping when routing, but I've been using this tape for many years on woodworking projects and it is a beast. It is Intertape 591 and you can get it on Amazon in a variety of widths.

Position it by aligning the template cross hairs with the lines on the body.

Hogged out some of the waste with a Forstner and a portable drill. My small drill press doesn't have enough "swing" to reach in far enough. Hogging it out does save some routing time, but I do it mainly to reduce the amount of fine airborne dust caused by the router blasting through the wood a 20,000 RPM.

Rout to 3/4" depth.

Removing the template takes quite a bit of force with a stiff putty knife. I need to apply force gradually, to make sure the template doesn't crack. This is another downside of a thin template.

Just thinking out loud, it could be that a flexible template conforms to any unevenness in the top of the body, so all the tape is fully engaged and thus reducing the chance of slippage. If the top is not perfectly flat, and the template is rigid, some of the tape will not make good contact with the body.