sMg Guitars

May 1, 2011

First thing this morning I took my little finger plane and smoothed the headstock down.

Since this little uke has a spanish heel, I need to route out binding channels between the top and the neck which can’t be reached by the bearing router bit.  I improvised with my dremel circle cutting jig mounted on a plate clamped to the body.

This worked well, and I proceeded to install the binding and purfling.  The bent binding came out of the bending machine almost perfect.  I only had to add a little more bend via the bending iron before proceeding.

First, the top binding and purfling was installed.  This side will also have abalam purfling, so the initial install uses teflon to create the channel to accept the abalam.

The back only has a small accent strip for the purfling.  I’ve used red to trim the binding at the sides, green for the top, and blue for the back.  Oooh, lots of different colors sure is fun.

Once the glue for the top dried, I removed the binding tape and the teflon, inserted abalam and flooded with CA glue.  Flooding will be several steps until the channel is filled and the CA glue (dried) is flush with the top.  The abalam actually rests below the surface of the top.

I’ve constructed a rosewood heel cap that will drift into the body at the back, which I will install after the CA glue dries.

April 30, 2011

This is one of my favorite parts of building:  Paua purfling.  I use abalam from the Duke of Pearl (apparently he invented abalam, which is appropriately laminated abalone).  I’ve settled on rosewood for the binding, and have prepared all the binding with red accent strips, then thinning it down to around .080″.  Four strips are sitting in the side bender overnight.  I’ll pull them out tomorrow and add more curve with the bending iron.  The channels are already cut into the body to accept the binding and purfling.  I do, however, still need to chisel out the channels where the body meets the neck.  The router bit can’t be taken too close to the neck so as to avoid putting big inappropriate divots in the neck, hence the need to chisel.

In the meantime, while the binding cures in the bender, I tackled the headstock.

April 26, 2011

It’s a uke!

April 26, 2011

Got a lot done today between printing lesson plans and teaching 9th graders how to divide exponents.  I planed and radius sanded the back until it was in shape to accept kerfing.

Lots to do on the inside before gluing on the back.  Side reinforcements go in, three to a side.

The soundhole needs to be reinforced with two spruce braces.

The ladder bracing on the back was trimmed back, and a label was secured to the back as well.  The soundhole is too small to get my fat mitts into to glue in the label, which is what I usually do with guitars.  The back was trimmed down at the waist to accomodate a clamp to press in against the side waist to square up the sides.

The back is glued to the kerf and held down with spool clamps.

Later tonight, after the glue dries, I’ll flush up the sides and it will appear to be a ukulele.

April 24, 2011

To recover from the wrong way heel slots, I filled with mahogany plates.

I had to carefully build a holding jig for the neck in the table saw which stabilized the neck while I drew it through the 5 degree angled blade.  Slots came out well, and I spent time shaping the heel in preparation for joining the top to the neck.

The top of the neck is routed out to accommodate the thickness of the top and ensure a flat transition from the top of the neck and the face of the top.  Center lines are matched, and the top is glued to the neck at the neck block portion of the neck.

Once the joint is dry, it can be turned around and mounted onto the workboard.  After several dry fit attempts, everything lined up well, and glue was applied to the neck slots and the glue line along the inside of the top where the sides meet.  I probably should not have glued the slot, as I need to shim a wee bit of the sides to press against the heel for a tight fit.  So, there is a little gap between the heel and the sides which I may be able to shim out, but probably not.  The gap is very small, and will disappear when lacquered (or I can fill it).

The sides are clamped to the top, and while drying, the kerfing process can begin.

April 23, 2011

I completed the bracing for the back and top today.

The bridge patch is rosewood, and the bracing for the top is flat (not radiussed) using sitka spruce.

The back is braced with 15′ radiussed mahogany ladder bracing.

My dyslexic brain allowed me to cut the slots in the neck for the spanish heel at the opposite angle.  The plan for recovery is complicated and will require me to build a jig to hold the neck and accurately cut the correct slots.  First I’ll patch the “bad” slots to return material to the neck block before I cut new slots.  The fortunate aspect of this problem is that the patch will only be visible inside the uke where the heel meets the sides.

April 21, 2011

Used a circle cutting bit for the drill press to produce the soundhole in the top.  I usually use a dremel and down cut mills, but the circle jig won’t adjust down small enough for the uke soundhole.  The top plate must be carefully positioned under the circle cutting bit as any off center positioning will show in relation to the installed rosette.

April 20, 2011

I enacted my theory to eliminate burning on the drum sander.  First, I replaced the sandpaper with a new roll and mounted it such that there is a barber pole install with a 1/8″ gap instead of butted flush.  Then I slowed the drive belt speed down to the minimum and began thickness sanding the koa back and top (should it be called thinness sanding?).

I took these plates down from .120″ to .100″ without any burning!  I’m smugly pleased.

April 18, 2011

Over the past two days, the headplate with a contrasting maple veneer was installed and trimmed.  Tuning machine holes were also drilled.

April 17, 2011

I always wanted to celebrate Dorky Day.  So today, I am.  See The Fan Man for more background.

Anyway, aside from Dorky Day, today was work on the uke day.  The mold for holding the sides is only that:  a holder of the sides until ready to mount to the top and neck.  I’m trying a little experiment, which may or may not prove worthwhile.  Since I experienced a bit of cracking of the sides when I was inserting into the mold, I wanted to ensure that further cracking wouldn’t occur.  I glued in the heel block and a “plug” on the neck end to hold the sides together as I pulled them from the mold to transfer to the workboard.  The plug on the neck side is smaller than the width of stock I’ll need to remove to fit into the spanish heel slots.

You can see the top of the plug insert sticking up between the clamps.  This is glued to the sides.  When I am ready to install the sides to the neck and top, I can use this plug as the guide for how much stock to remove before inserting into the spanish heel slots.  And, it will hold the sides in place as I remove them from the mold.

This holds true for the butt end as well.  In addition to gluing in the heel block, I added a plug (or patch) to the sides not covered by the heel block.

To kill idle dry time, I installed the rosette for around the soundhole.  This is an example of using teflon strips which are removed after the glued purfling dries, then inserting abalam and flooding with CA glue.

I further tapered and shaped the neck in preparation for installing to the top, and added ears to the headstock to accomodate whatever shape I decide to put it in.