Ukulele Part 4: Top to Bottom

First things first:  This post covers the "top" of the ukulele but I did install the back first (as you'll see in some of the below pictures).  It just felt redundant to show both sides as the process is mostly identical except the top requires more...
...well, more of everything...

What it is

This kit came with pre-shaped braces that just needed to be glued into place on the top and back.  They would have been fine as-is but I felt the need to monkey around with them.  According to many guitar builders - shaving down the braces can really shape the sound of the instrument. The basic idea is that the braces should be just strong enough to keep the instrument together but not so strong that they inhibit the top from vibrating - which is where all the sound comes from in a ukulele (and guitars as well).  I've even heard it described as removing just enough material so that the instrument doesn't self-destruct.

The above picture is how the braces came to me.
The below picture is after I was done with them

What it shall be

You can see that I tapered the ends but what you can't see is that I also gave them a haircut.  The braces were much shorter and thinner when I was done with them. For those of you playing the Luthier Home Game - I didn't 'scallop' the braces - I just made them thinner all around.

In my last post, I spoke about cutting a notch for these braces in the sides.  The reason I stated that some of the notches were unnecessary was due to the amount I removed in the above process.

What it was

There are three main tools to do this kind of work:  a sharp chisel, finger planes, and sandpaper.
I don't own any finger planes but if I ever get into making acoustics more often - I will invest in some.  The chisel worked but as you can see from my above efforts - it was a bit sloppy.
The sandpaper really helped clean things up after I was done with the chisel.

Also for the people playing at home - I did "tap-tune" the top.  This is a fancy way of saying that I stopped chiseling every couple of minutes and tried tapping the top to see how it sounded.  When the top stopped making a "thud" sound when tapped and started making more of a distinct note or tone - I knew I was close to being done carving the braces.

That don't look right

Just before I started working on the braces I became aware that the top had a pretty significant bow to it.  This would be fine if the bow was bowed in the other direction.  A slightly curved top is actually a good thing in an acoustic/ukulele.  A slightly concaved top...?  Not so much.

What I think happened here is that the weight of my clamps may have bowed the top when I glued on the braces.  The braces themselves were fairly flat.  And no - there was no difference in the size of the bow between when I started carving the braces and when I finished carving them.  This just is part of the top now, I guess.  We'll see...

Ready...?

I don't normally sign my work but the one previous acoustic instrument I built - I did.  So, it felt right to do so this time.  And since this was a gift from my wife...
...well, you get the idea...

1...2...3...

Awwwwwwww!

As you can see from the below photo - the back is already glued to the sides.  You may also be able to see the notches I was talking about.  Finally - you can see those screw-eyes surrounding the uke body.  Those are going to become important in a bit.

That's a mildly ukulele shaped thing, right there!

What may be hard to see in the below photo is that the glue has been applied and we're ready to put the top on.  I have the habit of overdoing it with the glue.  I haven't poked around inside of this uke yet with a mirror but I know there are some glue drips in there.  Judging from the amount of glue drips that I wiped up on the outside - it's not even a question of if but how many.

I'm hoping that extra glue is going to come in handy as we'll see in a sec.

sticky sticky

The green stuff is one big rubber band.  True story.  It comes with the kit for this very purpose.  And it does a pretty good job of putting even pressure on the top while gluing.  The trick is that your top can't have a bow in it and your sides need to be even for this to work as designed.  Neither of these things was true with my uke.  Sadly, also a true story...

This is where the screw-eyes come into play.  I threaded the elastic through each of the eyelets but if you used bigger screw-eyes you could wrap the elastic around them.  My way was a bit fidgety but it seemed to work okay.

Insert Dad-joke about being 'all tied up.'

 As you can see - it puts a decent amount of clamping force on the top.  Enough to squeeze out a lot of glue.  But it wasn't enough clamping pressure.  There were still spots where the top wasn't touching the sides.  This could have been because the neck or heal cap was taller than the sides (although I checked that) or it could have been the sides weren't even (checked that too), or it could have been that pesky bow that I mentioned (not much I could do about that one).  But I'm guessing it was all of the above.

That'll buff right out.

 So, we improvise!

Necessity is a motherf----r

That's about two feet of books sitting on top of the uke.  It helped quite a bit but there were still a few spots where the generalized pressure of two feet of books just wasn't enough - so I focused the weight with a couple of blocks and a stack of coins.  This really put the squeeze on.  There still ended up being one or two spots where the top and sides don't appear to be touching but I'll have to do a flashlight test after everything dries.

Is it me or does it look like the wood is bending?

What you don't see in the pictures is the gallon jug of windshield wiper fluid I put on top of the books.  If I had to guess there was probably 30-40 pounds of weight on that top - plus whatever pressure the elastic band was creating.  That's a pretty strong body.

Well, if all else fails it'll make a nice uke-shaped birdhouse.

Next up:  let's trim those overhangs and sand the body.

Soon

So round, so firm, so fully packed

I have yet to make a router template for the Les Paul body blank - so this build is on the back burner for a couple of days.  In the mean time I started working on the other body blank, which will be a PRS shape.

As you can see, I followed the same process for this build as I did with he last one: trace the body shape, make relief cuts all along the trace line, and follow the trace line with the jig saw to get the rough shape of the body.

The good news is that I already had a PRS template from an earlier build.
In brief, you trace a real PRS (or whatever guitar you want to duplicate) onto a workable medium that won't warp easily.  I used MDF wood but plexiglass would also work.  Then you cut it out using a band saw, jig saw, or similar sharp-toothed device.  You can then smooth out the lines/contours with sandpaper - either using a belt sander, drum sander or even just a a bit of sand paper wrapped around a dowel.  Being able to get into the curves is important - so a square block won't take you the whole way.
I used a "drum" sander attachment for my drill press and sandpaper wrapped on a dowel.  It worked well but the template is still made of wood (in my case).  If you are not careful you can damage it - which I did on a previous build with the router.  So my template is not perfect - but it is good enough to work with.

The usual way to use a template like this is to tape it to the body blank using double sided tape.  I probably used too much for this template (about 6 pieces running from the horns to the butt).  It made removing the template a bit harder than I had planned on - but I didn't have to worry about the template coming away from the body!  I ended up using three different router bits with this body blank.  All of them had ball bearings on them to trace the template.  You can buy them at Stew Mac, Rockler, or Woodcraft.  You can also get them at big box stores.  Click on those links to see what the router bit looks like.

The first router bit was 1/2 inch in diameter and a 1/4 inch long.  The second was 1/2 inch diameter and 3/4 inch long, the third was also 1/2 inch diameter and 3/4 inch long but with the ball bearing at the bottom of the bit vs at the top like the other two.  (BTW - I'm talking about a 1/2 inch diameter blade - not the shank/collet - all of these are 1/4 inch shank.)  By switching blades this way I was able to make small passes with each and not take off too much wood on any one pass.  The 3/4 in bit was too big (too long) to start with - so that's why I started with the 1/4 bit.  But the 3/4 but wasn't long enough to finish the cut because the body blank is over 2 inches thick.  If you are using thinner body blanks you should be able to get away with just using the first two bits.

The reason why you want to take your time and make small cuts is threefold:  The router doesn't have to work as hard, the bit doesn't get too hot,  the cut is smoother/better.  Routers and router bits aren't cheap - so making more passes will ensure they have a long life.  Also, if you work the router bit too hard you could break it.  The idea of a sharpened steel blade flying through the air at great velocity gives me the willies.

So, how much is too much?  I try not to cut away more than 1/4 of an inch at a time.  There are plenty of people who would tell you that's too conservative and plenty that will tell you that's too aggressive.   I'm just telling you what works for me.

As you can see in the pictures above and below - the different bits have left their mark on the body blank.  Those fine lines come from three different things: where I switched router bits, where there were imperfections on the template, and when I removed the template and used the body blank).  They are pretty minor and will sand out fairly easily.  Also, as you can see in the picture below - at some point you can remove the template and use the body blank as the template.

I do like the PRS shape and it's pretty comfy to play.

Seeing as this body isn't going to have a pick guard and is going to be carved in some way - I think I'm going to put binding on the body.  It's another step to add but I think it'll make it took pretty tasty when it's done.

So, up next is to make a Les Paul Template so that I can get that body up to speed with this one.  Then I think I'm going to have to make some router jigs to shape these two bodies a little.
Stay tuned!

Tear Outs (my hair outs)

So, until I decide what kind of a guitar I'm going to carve this body blank into - I shall dub thee: Number 2.  And to be honest - that's how I felt about this one after I spent some time with it - a little poopy.

This sat in the clamps for about 24 hours.  As I was taking the clamps off I knew there were three things about this body blank that were different than the other one (dubbed #1, for now).

Maple laminations that needed to be worked against the figure.

Yellow heart - which I've never worked with before.

The Mahogany was not as square as it should have been.

First the maple.  Maple is the R. Lee Ermey of luthier woods.  Maple is like, "Come in, sit down, and have a hot cup of 'shut the f--- up and do it my way!'  Flamed maple in my (limited) experience has a mind of it's own.  It's much harder than mahogany to chisel, scrape, and sand.  It's a denser wood.  And the kicker is that the beautiful figure (sometimes called tiger, flamed or curly) are the wood fibers turning and twisting - which seems to make tear-out a common occurrence.  Fun!

Second?  Yup, Yellowheart also has a propensity for tear-out it too.

I dodged a bullet with number three.  I was able to get a good joint with the Mahogany.  There are some noticeable gaps in one spot - but they will be scraps on the floor when I'm done.

So, let's plane those high spots...

Looks pretty, right?  Almost like I know what I'm doing, hmmm?  When you use a wood plane - you want those long, thin, curly shavings.  If you get really good at it they can be so thin they are translucent.  Take a closer look.  There are about four or five good passes in that pile.  The rest are closer to wood chips than shavings.  And that's because I have no idea what I'm doing.

Okay, maybe not "no idea" but close.  I'm still learning how to use a hand plane - so there were a lot of digs, dings, and tear-outs to the surface.  Take a look at the below picture.  This is the better of the two sides.  See all those dark spots on the Yellowheart?  Those are all tear outs.  The maple is in similar shape - just not in this spot

I tell you this not because I like beating up on myself - but rather as a cautionary tale: practice on scraps.  Learn to use your tools before you viciously attack your work pieces.  I am (as anyone who knows me will attest) a slow learner - just making the same mistakes over and over.

Here endeth the lesson.

I will say that this body blank will look good when I figure out the best way to work with it.  The wood combination is pretty sexy - and is only going to get more so when it's got some relief to it.

Hmmm...

Those clamps are free to glue up another lamination. 

...and I do have enough of this mahogany left for one more body blank...

 Sadly, this is going to have to wait a bit.  That wood in the middle (the reddish-brown one on the right) is called Cocobolo.  It is my favorite wood but it is also like trying to work with sticky steel.  It's hard as a rock (the wood doesn't float - it sinks) and it is so gummy it clogs up sandpaper and files.  That piece is rough sawn.  I'll need a thickness planer to even begin to work with that wood.

...hmmm...

Image is everything

The lamination sat in the clamps for about 48 hours.  I then brought everything back to the workshop - took off all the clamps - and was left with...

...at this point you may be questioning my taste.

Looks pretty ugly, huh?

Hold that thought...

There.  That's better!

So, what just happened?

After removing the clamps, I took a small surface plane to the thinner laminations (the lacewood, basswood, and purpleheart) because they were about an 1/8th to 1/4 of an inch proud of the mahogany.  Once all of the pieces in the lamination were roughly the same height I busted out the sander and some 60/80 grit sandpapers.  It's dusty work (and not really necessary at this point as we'll see) but it's hard to argue with the results.

Results.

Results.

Full disclosure - I also changed the lighting a bit and wiped the piece down with mineral spirits.  That's the real reason the grain is popping so much.  The mineral spirits gives you a preview of what the wood will look like once a finish has been applied.  The nice thing about using mineral spirits is that it evaporates quickly and doesn't raise the wood grain like water.

In the close-up images above you can really see the figure of the Mahogany and the 'laces' of the Lacewood.  

The truth is though - that everything after taking the piece out of the clamps and planing the lamination flush was a waste of time.  I am going to be carving the top of this guitar.

See the image below for what I mean.  See how there is a sculpted aspect to the shape of the top.  That's a carved top - and they are purdy.

This particular image comes from http://williamsguitars.co.uk

I'm not ready to carve this top yet - so sanding it was not really necessary.  I did it more for inspiration than anything else.  Hence the title of the post.  Image is everything.  Seeing what this is going to look like when it's completed is a motivating factor for me.  I want to see that final finish. That's why I've done this on each of the guitars I've worked on to this point.  Psyching yourself up can be the difference between the woodshed and the couch.  At least that's what I tell myself...

Back to business!

When I planed down the laminations I created a few-tear outs.  Mostly because I've never tried using a hand plane to smooth a surface.  Previously I've used card scrapers, rasps, and sandpaper.  But sanding 1/4 of an inch just takes forever - so I figured I'd try using the hand plane.  Once you get the blasted thing sharp enough and set up properly (and you are using it correctly!) - it's wonderful to use.

You can see one tear-out in the Mahogany in the below picture.  It's the little black spot just above the laminations on the right.  At some point I'm going to need to sand, scrape or fill that hole.  

It was caused because I was planing against the grain of the Mahogany.  I was planing with the grain of the lacewood - but when I glued the Mahogany to the lacewood - I glued them with opposing wood grains.  Would an experienced woodworker have done that?  Probably not.  But also remember that plywood is stronger than regular wood because the laminations have opposing grains.  So, what I'm saying is: Could be good.  Could be bad.  Time will tell.

I was concerned that there might be gaps in the laminations - either because I didn't prep them well enough (read made them square) or because I didn't squeeze them hard enough when clamping them.

I seem to have done okay.  There are a couple of gaps but if I play my cards right - they will be scrap wood on the floor once I cut the body shape out of this blank.  Again, time will tell.

In short - I'm happy and ready to move forward with this build.

So, now that I've freed up all of those clamps I guess it's time to look at that other body blank...

Hmmm...

Round 2: Fight!