Step 2: Making the Jig

A tenor uke has a 17" scale. I want to put the bridge in the middle of nowhere on the lower bout, which in this case is 7" from the neck joint. So there is 10" of neck before I hit the nut. I'll give myself 11" of neck on the jig before the head/neck transition, and trim off what I don't need. This uke will be a 6-string, so I'll need about 7" of head for the tuning machines; and one to grow on makes an 8" head on the jig.

Start by cutting two straight sections of 2x4s 20" long. Dampen a 2" side on one of the boards and run a bead of Gorilla glue down the center of a 4" side of the other. Clamp and let dry, scraping off any squeeze-out before it hardens.

Now cut a 14 degree wedge from the spine of the jig, 8" from one end. A miter saw makes this easy, but you can cut it by hand, too. For a triangle with two sides spanning two 2x4s (actual depth being 5") the short side will equal 1 1/4". Draw this triangle on both sides of the spine and cut carefully, watching both sides as you go.

Tape the acute angles tight against each other. Urethane glues excel at binding wood by the end grain-- dampen one side, apply glue to the other, then stand the jig upright, letting the tape act as a hinge and the weight of the 2x hold it in place. Let dry, scraping off any squeeze-out before it hardens.

Mark a line about 1/2" from either side of the joint. With a rasp, round the edge back to the line to make a smooth transition.
Very interesting, thanks for sharing. <br><br>Your English is too rich for me, please translate Thhpt, I couldn't find the meaning.
My apologies. It's spelled &quot;Thppft&quot;. <br>Sorry for the confusion.
Thanks, but for Thppft I neither found the meaning in Google.
It's functionally like a sigh; not really a word. Something for when words fail you. &quot;Thppft&quot; is the sound of &quot;blowing a raspberry&quot;, where you stick you tongue out and blow. This has the double function of making an inarticulate, derisive sound, and of letting you flap your tongue at the thing that is frustrating you.<br>In this instance, I was expressing frustration that most people don't approach guitars (building or playing; or for that matter drawing, or cooking, or love, or conversation) with the same zeal as a child with a kazoo.
OK, thanks.
I am facinated with your laminating method. Having done many laminate pieces, I've never used fiberglass cloth as an intermediate layer, nor have I used gorilla glue with the cloth, it has always been epoxy or polyester resin for me when glassing. My question is, do you think the cloth is a necessay step and why?
Fiberglass is extremely rigid even in compression when encased in glue ( <a href="http://en.wikipedia.org/wiki/Fiberglass#Properties">wiki</a> ). If you used a stronger wood like maple or even mahogany the 'glass wouldn't be strictly necessary, especially on a uke, with its short scale and nylon strings (meaning that it needs little tension to create a high pitch).<br> <br> But I figure: it's already apart, and the glass should add quite a bit of strength and rigidity, and allow for a lighter neck. I think a light, rigid neck has better sustain and bandwidth.<br> The skeptic in me groans at this. I do need to run more tests. That's another appealing aspect of ukes-- they are structurally miniature guitars, and the steps to build them really are the same, just scaled down. So I can build a series of necks with different specs and techniques and (hopefully) work out what is useful/resilient/consistent and how the specs and techniques affect the sound of the instrument while expending less time/resources. While a uke doesn't NEED as strong of a neck as a steel string baritone guitar, it is nice to know that you could bludgeon a velociraptor to death with it and still play sum tUnE-YarDs.<br> <br> Of course my Google-fu is failing me now, I can't cite the following but I'll see if I can find something concise later (Groan-- Skeptic-In-Me): Gorilla Glue is a polyurethane, and is actually closely related to resins, in that moisture acts as a catalyst. It does not set by evaporation.<br> Epoxy would be stronger, but not by enough to justify the difficulty and expense. In large quantities (the gallon jugs one could get at boat building shops) it would be a good way to go, and while I aspire to one day go through gallons of glue in a year (I am now recalling a stair-building company I worked for, with 55 gallon drums of Titebond on tap. Sigh.), I am not there yet.&nbsp;<br> <br> The uke neck used about 3 ounces of Gorilla Glue. So. Gorilla Glue is just that more useful and convenient that I'd rather have a bottle of that laying around.<br> <br> I have made a 31&quot; scale baritone guitar using poplar, without a trussrod, using this method, and even tuned it up to standard tuning before I learnt better (and broke a few strings). It deflected from perfectly flat to slight relief. No velociraptor has menaced me as of yet, so that final test is untried. But I live in hope. What is your experience with lams/epoxy? I am pretty new to the technique. I may be repeating old mistakes.
I've done things like vaccuum forming large boats using epoxy as the bonding agent to great sucess. I've done many smaller things too, from guitar stands and curve legged tables to fishing nets. I hate straight lines and laminating is far more controlable than steaming. You are spot on when it comes to the strength,, while there seems to be fewer and fewer velociraptors around these days to test the strength to weight aspects of the method I'm sure a panda would be a suitable test bed. On the down side of epoxy, the cheaper qualities are prone to failure after a few years and the seam lines tend to be more visable. PVA glue is a very suitable glue but I don't think it would work as well as gorilla glue when using your glass cloth method which I am going to try very soon.
One thing I didn't explicitly say regarding polyurethane glues: like epoxies and hot hide glue they are extremely rigid. PVAs can be a little mushy, and that could absorb vibration, much like Green Glue (an acoustic isolation compound).<br> It can also allow for creep in the joint. A little movement along the length of a lam can translate to a large movement on axis. On a guitar neck, where reflex is measured quite intimately and minutely, a little creep would be ruinous.<br> <br> Reminds me again of stairbuilding. The rhythm of climbing stairs is also measured intimately and minutely. If you find yourself tripping over the same step repeatably: measure it and the surrounding stairs. The offending stair might be proud a mere 3/16&quot;. An embarrassingly small amount to trip over, but over you go.<br> <br> Maybe it's not a big deal, using urethane instead of hot hide or epoxy or PVA. I don't know yet. We'll work on it.&nbsp; Please let me know how it works for you.<br> <br> Big boats! Sounds like fun! I hold a secret desire to build a big sailboat and just bum across the seas. It's still secret! Thank you, anonymity of teh internets! Also, pandas seem like small mountains. I lack the faith to try walloping one.
The pictures of the Gibsons with the broken necks made me weep a little.

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