Crawls Backward (When Alarmed)

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Measuring for the Neck Reset on Regal Tenor Guitar

Oh wow.

I just realized that I've been working on a Princess banjo-mandolin, and now I have 2 Regal tenor guitars in process too!  Royalty is in the house. I suppose I should roll out some red carpet in The Dungeon! 

Monaco or San Marino, this ain't.

So I have some new tools from Stew-Mac to use on these neck resets.  One of the tools will be super useful I think, one will be medium-useful, and one may just be a bit overkill.We shall see.

So, when one does a neck reset, the first order of business is to measure the amount the neck is underset.  On the left I have an old picture I took when resetting an Ovation guitar.

The process is simple:  with the strings tuned to proper tension, you lay a long straightedge on the frets parallel to the strings and position the straightedge so that it contacts the bridge.

If the straightedge sits just on the top of the bridge, the set is correct.  If it contacts under the top of the bridge, as we see here, the neck is underset.  We then need to measure the vertical distance between the top plane of the bridge and the point where the straightedge contacts the bridge.  We'll then use that measurement in a formula to determine how much material should come off the bottom of the neck heel in order to correct the neck set.

In the past, I've put a pencil mark at that contact point, and then measured the distance as best as possible with a small ruler.  It's a small measurement, and it's not particularly accurate, when you consider there is the width of the pencil lead and the fact that there are tiny fractions of whatever measure you are using - maybe between 64ths of an inch or fractions of a millimeter.

The accuracy of this measurement will determine the accuracy of the amount calculated to remove from the heel.  If you have an accurate measurement, you'll spend less time taking off a small amount of material, testing the set, taking off some more, etc.

Enter the Stew-Mac neck set gauge.  This tool is essentially a dial caliper you bolt to the end of your straightedge and line up with the bridge.

The dial is calibrated in .001 inch divisions.  One thousandth of an inch.  That's .0254 millimeters.  We're talking a very small amount here.

It's very easy to take this measurement with the gauge.

Line the straightedge up as you would usually do.  The straightedge will naturally "point" to the place it would contact the bridge.

Then take a measurement from the top of the bridge with the gauge.  You can see this in the closeup picture.  I illustrated this on the image as well.

The gauge will record the difference between the underset point and the top of the bridge - accurate to a thousandth of an inch!

On the small Regal tenor, I measured an underset of .1026 of an inch.  No way I could get that accuracy with the pencil-ruler-and-eye method.  I think this is a super useful device.  Not too expensive either - it could pay for itself after a reset or two. 

I'll do the math for the actual wood removal after I get the neck off.  For now, I just need that 'golden' measurement.

Now for the tools that may be overkill.

I need to talk about a physical concept here.  When you release the string tension on an acoustic instrument, the top will tend to deflect downward, since it's not under tension.  The amount of the deflection depends on a lot of things - the string length, the number and gauge of the strings, and the size of the body. I would guess you'd see more deflection on an larger, longer scale instrument than on something like an ukulele, mandolin, or the tenor guitar we have here.

If you think about it, if the top of the instrument goes downward with no tension on it, wouldn't that affect the height of the bridge and also therefore, the measurement we just took for the neck set?

Yes, it would. If we just had some way to measure that deflection and then account for it when we do the reset.  Hmmm.

Which brings us to potential overkill tool number one.

A top deflection gauge.

Crazy.

What you do is put it on the top of the instrument at the bridge and zero the gauge - see the picture.  See how I used a square behind it to ensure my reading was accurate - and the location of the gauge was exactly repeatable.

Then take off the strings.

Take a second measurement with the strings removed, and you, my friend, have just measured the deflection of the top of the instrument!

In this case, it measured .019 inches - nineteen thousands of an inch.

So what now?


We remove the strings and employ the tool that will allow us to account for that deflection by raising the top of the guitar back up to where it would be if it were under string tension.  To do that, we place a scissors-type brace jack inside the guitar and crank it up .019 of an inch.

While I said the gauge and this tool may be overkill, this jack could be useful for things other than neck resets - for example, it would be good for regluing loose braces inside a guitar body.

I have a few of the inexpensive turnbuckle-style jacks, and I've had mixed results with them.  It's extremely hard to adjust them when they're deep inside a guitar.  Cheap, but you get what you pay for.

When I saw this brace jack in the Stew-Mac catalog, I pondered about getting one.  Then I decided to get one when I realized I had 5 (I think) neck resets waiting in the queue.  But the real impetus was after Toy Making Dad said to me, "That looks like a clever tool.  I can see where that would be useful."  Of course, he didn't offer to finance it.

It's a nicely made jack that adjusts with a 4mm machined square drive on the screw that raises it.  It comes with a long flex hose to attach to the fitting on the jack.  In theory, the long flex hose is a good idea, but in reality, it doesn't work well, mainly because it's hard to get a lot of torque on it when the jack is in position.  However, you also get a knob which you can attach to the jack instead - if you can reach the jack to turn the knob.  And, since we know the size of the adjustment screw...well, hold that thought for now.

The jack also comes with two neodymium boride magnets.  They're really strong.  I have some others around here, and boy, do then SNAP together.  Talk about opposites attacting - these things are the Tony and Maria of magnets.

They're so strong that there's a warning label in the box with the jack.  Not only will they demagnetize stuff, they could pinch your fingers if your fingers got between them.

Potentially dangerous, but very useful.  Sort of like a magnetic version of a table saw.

In this instance, you can screw one magnet to the jack, and use the second one to locate the jack within the guitar. 

It took me a while to figure out how to get the jack into the small tenor guitar body, and how to get something strong attached to the jack's adjustment rod in order to, well, jack the thing up.

Finally I came up with the idea of just using a 1/4 drive ratchet.  You can see I had to tape the socket to the jack - I say it's a 4mm drive, but not exactly.  Nor does it seem to be an exact Imperial measurement either.  All I can tell you is it is resistant to sockets or wrenches, which slide off easily.  Hence the tape.

I need to get the jack under the bridge of the guitar so I can raise the top up.

Took a couple tries, but I got the jack positioned under the bridge location.  In the picture on the left, I used a mirror to attempt to show the brace inside the guitar.

I did try jacking it up, but on this guitar, the bracing is so light that the jack actually pushed the top and the back outward.

What I'll do is take the neck off, and then clamp the body down so the back won't flex, then I should be able to jack the top that .019 I need (sounds a bit crazy to account for such a small amount of deflection, but there you have it) and go from there.

Stay tuned.  Will all these measurements may the reset easier and more accurate?  They better!

 
 

Regal and May Bell Tenor Guitars - Initial Repair Assessment

The Princess banjo-mandolin is still down in The Dungeon waiting final assembly.  I confess that I made a small goof and had to do some touch-up on the headstock.  So I'm waiting for the lacquer to dry so I can rub it out.

In the meantime we have a exciting interesting new project.

Not one, but TWO Regal-made tenor guitars!

The one on the right is a Regal-labelled small body model belonging to a good friend.  And the one on the left is mine.  It's clearly made by Regal, but carries the "May Bell" brand/logo used for their line of guitars, banjos and mandolins.

I'd guess both instruments date from the 1930s.  Neither one has a serial number that I can find.

Both of them need neck resets and some other minor work.

They both have solid spruce tops with birch backs and sides.  And they're both quite charming!

The smaller one measures about 10 3/8 (about 30 cm) across the lower bout.  That's about an inch smaller than a Size 5 Martin.  I haven't measured the scale length just yet.

Here's the headstock of the smaller guitar - bearing the Regal logo.

Come to think of it, I have a book on Regal guitars!  I'll look these up and see what else I can find out.

The Regal logo.

Regal cranked out thousands of instruments through the 1920s and 30s. Their build quality is not as good as Martin's, but they use solid woods and are decently made.  I'd guess they cost a third of an entry-level Martin, so you get what you pay for.

Look at the braces as an example.  They look a bit unfinished.  Functional, but not much beyond that.

Here's the birch back on the smaller guitar.  Birch is sort of a second-tier tonewood, but it's decent for an inexpensive instrument.

I really like the contrasting black binding.  Looks great.

The guitar has an archtop-style bridge.  My guess is it's something like pearwood dyed to resemble ebony.

Don't you love the way that old nitro lacquer gets that amber look over time?  I just love it!

We have a "Bell Brand" banjo-style tailpiece.  This will look great after it gets polished up.

You probably won't be surprised to see banjo-style friction tuners.

One of the plastic knobs broke and someone cleverly used a wine cork as a replacement!  It works pretty well, but I want to put modern planetary geared banjo tuners on it.


The larger guitar carries the May Bell brand.  Regal made a lot of banjos with this brand name.

The headstock shape is just like a banjo's.

Again, we have spruce over birch.

This guitar has a LOT of playwear on it.  I was initially thinking I'd refinish it, but I've decided to leave it as is.  It has a ton of mojo!

Check out that string height - it's probably about a half of an inch (12mm) or so.

Another friend who is a great player calls that high action "cheese slicer" height.

The back of the guitar is stained (or toned) reddish-brown in an attempt to make the birch look like mahogany.  Nice try, but we know what it really is.

Not that birch is a bad thing.  I like the grain pattern.

Nicely shaped bridge.  Again, we have some unknown type of wood stained black to look like ebony.

I'm actually thinking about making an ebony bridge to replace this one...still pondering.  Would it ruin the collector value? (Ha ha).

And again we have the usual friction tuners.  These are painted silver - I can't tell if it was done at the factory or later in the guitar's life.

As with the smaller guitar, I'll be replacing these with planetary tuners.

Here are the two tenors with another 'second-tier' vintage guitar - another Kay jumbo that's waiting in the queue for repair.

We never have a shortage of projects in The Dungeon!

 
 

Refretting the Princess Banjo-Mandolin

Finally got a chance to get back to the Princess banjo-mandolin.  I'm looking forward to finishing it since I have other projects in the queue.  And my friend is probably wondering where on earth her little Princess has gone to.

Originally I had planned to just level and crown the old frets.  But with all the handling, they all started falling out!  The old frets are so tiny and fragile that they bent if I just looked at them, so a refret was in order.

Here I am pulling out the last few old frets.  You can't get modern fretwire quite this small.  The new fretwire is close, but's it's a bit taller.

Note the infamous Green Gunk® that lives in the fret slots of all old fretted instruments.  It got cleaned out during the refretting process.

I gave the fingerboard a light pass with 320 grit paper on my corian fret leveller to ensure the board was flat.

You can also see my new Stew-Mac guitar repair vise.  I was thinking about getting one for some time, and I'm SO glad I did.  You may be able to see how the jaws swivel to hold odd-shaped things such as headstocks.

The quality is ok...the paint job is not the best and the fit of the drive screw is so-so.  But it's a great vise, especially for the money.  I'm going to finish the raw wood on the jaws with Tru-Oil I think - they're already getting marked up.  There is a soft urethane pad on the jaws to prevent scratching instrument finishes...a nice touch.  And I love the crank knob - fun and useful at the same time.

A lot of reviews on the Stew-Mac site say something like "I can't believe I lived without this."  I agree.  It makes this kind of work so much easier.  I would have been chasing this neck all over the workbench trying to work on it.

Now we deepen and widen the old fret slots to take the new frets.  I needed to deepen the slots about .050 of an inch, so I just measured that distance up the fret slot saw and set the guide there.

A couple of passes and we have slightly bigger slots.

The fingerboard is so delicate that I started using the old hammer method with the frets, but I found that since the frets were so small and relatively short (across the board) that the middle would be set but the ends would tend to bend upward.

So I put the fret press to work, carefully and gently.  They came out fine.

I still needed to seat the frets with a hammer on the section over the neck heel and on the fingerboard extension.  I ran them through the fret bender to put a gentle curve on them, which helped keep them straight when hammered in.

I'm not going to show the leveling, crowning and polishing - I've described that on other posts.

But I did want to show how much metal gets into the crowning file on a job like this.  I did about 20 back-and-forth passes on 2 frets and you can see how much material got into the file.  I have a small file brush to get it out.

I find that I clean the file after 2 or 3 frets.  You need to keep the teeth clean or they'll just clog up and will just scratch the frets instead of filing a crown on them.

Here's the finished board after the refret.  You can see some crack fills here and there; these will be less visible when I put finishing oil on the board.

Also note how I supported the fingerboard extension with a wood block (green arrow).  The board is so thing and flexible that I was concerned it would snap off.  Need to treat it gently.

Now I can put the Princess back together!

 
 

Finshing the Lollar El Rayo and Cavalier Pickup Install on the Tele

I have a new pickguard for the blue Tele. Needed to put shielding on this one, so I just used spray adhesive (3M "45") and aluminum foil.

I do have some copper shielding, but I was too cheap this time to use it. The aluminum works just about the same way, and especially on a pickguard it's not as critical as a control or pickup cavity.

Used a wooden roller to smooth it out, still wrinkly but who will see it?

Stuck the new Lollar El Rayo onto the pickguard.

Wait until you see the pickup cover.

Like most of the universe, I use audio ("A," or logarithmic) taper pots for volume controls. And linear ("B") taper for tone.

But the only log taper 250K pot with a switch on hand has a splined shaft, such as you would use on a Strat or any knob with splines. Our wonderful Rutters knurled knobs have set screws and they'd be wobbly on a splined shaft.

Not to panic.

A few strokes with a file in the spot where I want the set screw to be and we're all set.

I like the set screws to face straight up when the volume and tone are all the way up. That way I have a visual reference.

That's where I filed that 'flat' on the volume control shaft.

And - it fits perfectly and doesn't wobble!

One other slight repair to do.

The screw hole for one of the screws on the control plate is stripped, so the plate isn't held down tightly. You may have experienced this on screws that go straight into the wood.

I'm using a trick from Dan Erlewine's repair book for this fix.

Put some medium CA into the hole. I only had black on hand - color doesn't matter.

I suggest masking off anything you don't want to get glue on :-)

Wipe off the excess glue, then break some toothpicks into pieces.

Stick them down into the superglue-filled hole.

Let the repair dry.


When the glue is dry, cut the toothpicks off level with the guitar.

I'm using a flexible flush-cut saw. It's really sharp; you have to handle it with care or it will become a flesh-cutting saw.


I ran a bit of 150 grit sandpaper over the toothpicks to ensure the fill was level.

Here it is. A nice filled screw hole.

I didn't bother drilling a pilot hole - the screw cut into the soft toothpick wood easily.

It's a nice tight fit now.

Since I had adjusted the neck flat in order to do the fret level, I need to adjust the truss rod after I string it up to pitch.

Now you see why I cut that new access slot into the body. I can just put an adjustment too right into the end of the rod without removing the neck.

All done.

I got the El Rayo pickup with a pearl cover to match the new pearl pickguard! Pretty cool. Lollar sells a bunch of different varieties for the cover...including tortoise. Hmmmmm.

Another shot of the guitar.

How are the pickups?

The El Rayo is simply amazing! Plenty of power and the best clarity I've heard from a humbucker - nice clean round top end. Very balanced. With the tone rolled off, it does a good jazz guitar imitation. With the stud coil cut, the tone is the same - just quieter, which tells you something about the basic tone of the pickup. I'm loving it!

The Cavalier is equally great. Really clean and twangy on the 'Bakersfield' tap, just like the name implies. And the 'Fat Lion' is fantastic. Lots of power, more midrange, but the treble is still smooth.

 
 

Lollar El Rayo, Cavalier Twin Lion Pickup Installation on Telecaster

Now I'll put the new pickups on the Tele.

In my search for a humbucker with more clarity than the usual humbucker, I came across the Lollar 'El Rayo.'  It promises to be clearer and cleaner.  In fact, the Lollar website says "Don't like humbuckers?  Think again."  So I sprung for one.

The pickup itself is impeccably made, like anything from Lollar.  You may recall I have a tapped Lollar P-90 in my ES-225, and it is just fabulous.

The other pickup that's going in is a Cavalier 'Twin Lion' from Cavalier Pickups.  Cavalier is a  custom shop run by Rob DiStefano.  The original pickup was one of Rob's stock ones, and I really liked it.

I liked it so much that I wanted to try another one - in this case a tapped Bakersfield/Fat Lion model.  The Bakersfield tap is about 6.3k and the Fat Lion tap is about 9.6k, both measured on my Fluke DMM.

I had gotten El Rayo with 4-conductor wiring so I could wire it with a coil shunt switch.  And of course, there are 2 taps on the Cavalier pickup.

I wired them both up with push-pull switches.  The Lollar is on the neck and the Cavalier is on the bridge (duh).  So now I have 2 push-pull switch pots on the guitar.

Tested the wiring, and it worked fine.

But then I ran into a slight obstacle.

For whatever reason, there is a raised 'block' in the middle of the control cavity.  This raised area is fouling the volume control switch. Dagnabbit!

Now, every Tele I've ever worked on has had the old-style flat bottomed cavity.

Like the missing truss rod adjustment slot we saw in the last installment, this too has me scratching my head. 

What to do?

Out comes a chisel and hammer.

I make like Lenny DaVinci carving a statue and have at it.

Only difference is that this isn't art!
Thwack, thwack, thwack.

Not quite as easy as the truss rod slot, but just as effective.

A big rubber mallet is such a good thing to have when working on guitars, don't you think?

You can see the bare wood where I removed that silly raised area in the cavity.

I sort of understand the truss rod access not being there.  A lot of 'modern' Teles don't have a heel-adjust rod.  Ok.

But this I don't understand.  Wouldn't it be easier to rout the whole cavity flat like our hero Leo did in the first place?

Anyway.

We just glue a small piece of aluminum foil (the poor man's RF shielding material) over the bare wood and we're back in business.

I also consolidated a couple of ground leads so there are a couple less connectors at the star ground.

Now we move on to Final Assembly.