Videos of number 75, and a few others

I sat down yesterday and made a demo of the recently finished koa concert, number 75.

And then later I grabbed a few more ukes and made this:

They might go in and out of tune but hopefully you can hear the differences, which were quite big at least in the sofa. My boy Johan was very excited and I might start using his newly fangled words next time I describe differences in sound!

Finishing

The koa concert needs either the final "glaze coat", which so far has proven to be very difficult. Or a buffing with some polish compound. I might settle for the latter, that at least I know how to pull off. 

The walnut tenor and the mahogany piccolo (sod secrecy; here it is) are sealed, almost pore filled and ready for some more shellac. I could do another session of pore filling but have yet to decide exactly what I'm aiming at with these two. Semi-filled pores might be just right. 

Here's the concert. Rather cool figure. 

I gave the piccolo and the tenor a few more coats. It's starting to build up nicely. I'll let it shrink back a couple of days, then scrape it with a card scraper and start the french polishing work. Up until now I have avoided oil, but will use it from now on. I use walnut oil instead of olive oil, my experience is better with the aforementioned. If I understand it correctly, it dries together with the shellac and gives a tougher finish. Be that as it may, I don't have to wipe any excess off between coats. 

Workshop glimpse, early November

Oops, we're in November already and October didn't see much action on this blog. Sorry about that, especially since I keep referring prospective buyers here. 

The explanation (which is not an excuse) is I've been abroad in work and then I spent a wonderful week's vacation at the summer house. But the project there is building a sauna at the moment. 

But things do tend to happen in the Argapa cave even if I don't publish enough. So tonight I'll show you some pics of the concert and of the bridge to the walnut tenor. 

The koa concert is on the home stretch. I've given it its wash and build coats of shellac and scraped it back. My new method of doing these coats cut a week from finishing, at least. 

Then some pics of that bridge. I showed you the one I made for the concert, this will have wings but I chose the same wood and the same tools. I considered ebony but that's so hard to plane and carve. And I thought this bridge would go nicely to the headplate veneer. 

The only machining I did was cutting the slanted saddle slot on my mini table saw, before and after that it was only edge tools. No sandpaper or even files. 

In this first pic you can see how I chisel away the end to make a wing. On the first end the grain direction was helping me, on the other end it was really tricky. 

Here you can see the wing after paring for a few minutes. 

The other end done, and a couple of facets. 

Two curves snuck into the design while nobody was watching. 

I love freehand carving. Never will I settle for a bridge design and crank out twenty at the time, it's so much more fun to let them grow into shape depending on the piece of wood and my mood. 

I think the walnut shows some promise, don't you?

(What I haven't shown is the custom piccolo. It's taking shape but it's gonna be a surprise for someone. Anyway it got its fretboard glued today.)

Bridge shaping

I found a piece of really hard mahogany which will make a good bridge. I shaped it with nothing but a chisel and my Leslie Nielsen no.1 plane. Both razor sharp. 

A dry fit, or more exactly; the bridge lying on top of the soundboard. 

Improved fretting

Fretting time! On the koa concert. I've decided to try a method reminiscent of the one I use on the piccolos, which are fretted directly into the neck. 

On ukes with fretboards, I've done it like this: http://argapa.blogspot.se/2013/10/fretting-fretboarding.html

I've cramped the fretwire into the fretboard before cutting it to length, then snipped it off with pliers before filing and sanding the ends flush with the board. It works well enough but I want to minimize the risk of protruding fret ends if the fretboard dries out. 

Since it isn't possible to file and sand the frets on the piccolos I undercut the tang and shape the ends before pressing them in, and it's the undercutting I'm going to do on this fretboard. 

Here you can see what I rant about. The tang is cut at a 45 degree angle. 

To get the length right I measure it at the slot. Always start with the longest ones; if you make them too short just move it a step or two closer to the nut end. As you can see that happened on the first fret tonight, that's why there's a seated one in the 14th slot while I'm working on the 15th. 

Give one end a tap with the hammer. I use a brass hammer on which I file and polish the face regularly. 

Then I use my lowlife cheapo fretting pliers. You can see it in more detail here:

http://argapa.blogspot.se/2013/07/new-gadget-for-fretting.html

I start at one end and work my way across. It works really well, at least well enough for me to forget about the upgrades between the occasions it's used. 

In the last pic the whole board is fretted and lies on the neck. The slight backbow disappears when it's glued on. 

I will show the file work in a later post, on this fretboard or on another. 

Glueing back on the koa concert

Humidity is down and once again it's safe to glue larger pieces. Tonight I'm working on the koa concert I have in progress. This particular koa wood has been a bit of a challenge but I think it'll all be fine when I'm done. 

First I chop out gaps in the cross banding strip. Remember, I build the bodies with the back braces in place before I fit the back. 

How stupid. The picture is upside down. But no matter. 

After the notches are cut I test it in place. 

And then I spread glue and clamp it all down. A couple of go bars complete the setup but the screw/slat arrangement is really good. 

I should also mention that I set the final neck angle by placing a shim under the nut end of the neck before I clamp the uke to the workboard. 

After tightening the wing nuts I check for squeeze out with a small mirror. Had my workshop been of proper scale I would have wandered round my big ruobo bench and looked from all sides but as it is I use a small mirror. 

Bracing and binding

Since I got back from the Middle East I've braced the concert soundboard, glued it to the sides and worked on binding both the concert and the tenor. 

I shape the braces with a large array of tiny planes. It's resting on a mouse mat that I bought on sale, and you might remember the Dust-E-Whacker. 

This concert will be slightly narrower than my other ones, the sides were a little shorter than I had wished. 

I routed the binding channel on the walut tenor. And it's an easy wood to work with, no surprises and no splinters or tear-outs. But I have to wear a dust mask. 

The last pic shows the binding installed and taped, and the concert has been routed as well. On both I bent a single piece of mahogany binding, but that is unnecessarily difficult really. You have to be really careful to avoid gaps which will appear if the distance between the two waist bends isn't exactly right. 

Progress

Well I have pressed on with the acoustics. Since the humidity was a bit high in the shop (and everywhere else) I didn't wanna brace any tops. So I concentrated on the sides and put the blocks and the kerfed lining in. 

Installing neck reinforcement rods

I know it's rarely needed, but I see other builders do it and argue for it so since I had some carbon fibre rods at home I wanted to give it a go. Five necks; three sopranos, a tenor and a concert.

I cut the rods to length, roughly from the heel end and back to the first fret. Then I sliced them diagonally to wedges, thinking the thinner end should go towards the headstock where the neck profile is slimmer. But why, you might wonder, strengthen the fatter part more - that'd be strong enough already. Well there's more wood there and my feeling is that a thicker piece could warp more if humidity and temperature would play up. 

In the pic there placed on the neck backwards. 

Then I was going to place a block of 12 mm thickness at the first fret location and run it across my mini table saw, to get the slot to even out to zero where the wedges end. But the table on the saw is tiny and the block wouldn't make contact at first. Bummer! I really did not fancy making special wedges for each neck size!

But wait..! Wedges? I had wedges already didn't I. After an unprecedented stroke of genius, this is what I came up with. 

I superglued the sliced rods on some wide masking tape and Bob was, indeed, your uncle. Or my uncle. 

After running it over the blade a couple of passes (blade is 1.5 mm and the rods 2) this was the result. 

And after 10 more minutes this was the result. 

Clever, huh? And the tape already in place in time for glueing! Out came the epoxy. 

You'll notice that not all pairs are centered, but they will be. I avoided some sapwood on one and a chip out on another.

I feel so good about myself I'm gonna publish this method on various fora.