Official Luthiers Forum!

Thought I'd have a go at carving necks on the lathe as I'm on with a batch of ukes just now. It's great! Two necks in five minutes with a perfect straight taper. It would work for D shaped necks too. Thise of you with a bit more lathe experience may know how to do a vintage V.




I worked out the taper for the using a compass, paper, trial and error. It didn't take so long and worked out fine.

But if anyone out there is a whizz with maths and knows the formula, that would be great. You know your desired depth at either end of the straight section and your desired width. It is then a matter of working out the circle diameter that produces the desired result. From that, you can work out jig thickness at either end. For some necks with a shallow depth taper, the jig will have a uniform thickness. My necks differ quite a lot from body join to nut, so the jig was tapered.

_________________
nigel

http://www.theluthierblog.com

Interesting, 2 at once?

Yep.

_________________
nigel

http://www.theluthierblog.com

Tell us more! (With smaller pictures)

Not much more to tell. I watched this video on Youtube - Ken Timms has a great way of building:



I'd highly recommend trawling through his videos. He has a great engineering mind.

After watching this, I asked pal who makes Northumbrian pipes on an old British engineering lathe if he could do it for me - he said he didn't have the taper attachment Kens' South Bend lathe has. And not many lathes do apparently. So I figured it would be possible by hand on a regular wood lathe. I popped down to see some pals who have one to try it out and it worked a treat. I'm buying a lathe this week!

I used a heavy bowl gouge, then a file, then sandpaper. With a bit of practice, I should get a nice sweep into the head and sort out the heel curve in the same sitting.

That video tells you all you need really. Or at least it was enough for me to work it out.

If anyone is good at geometry though, they'd be able to work out the correct size of jig without all the trial and error. Mind, even with a compass and paper it was about 10 mins of head scratching. I make 4 strings, 6 strings, 8 strings, 10 strings and occasionally 12 strings. I also use 13", 17", 19", 21" 24.75" and 27" scales. SO there are many combinations and I need many different jigs to get the thickness/width needed for every neck. So a formula would be handy.

The good news is 95% of the necks I make are C shaped so this is perfect for me.

But with a bit of thought, and a big enough lathe you could probably radius and slot fretboards a dozen at a time on something like this. You could also do D necks and V necks. There are lots of possibilities.

_________________
nigel

http://www.theluthierblog.com

I modified the sub base on an old Makita router so the base will ride over the ears of the peghead of one piece necks and use a roundover or ovolo shaped bit to mill guitar (and uke) necks. It will also give you the semi-finished heel shape if you go with the Gibson style. Just another and probably cheaper way to accomplish similar result.
Metal lathes are nice if you have the money and space for them. I am happy enough with a wood lathe which only gets occasional use.

That's awesome!

Nothing new under the sun as they say. It's a very old method, 200 years old.

Wow, slick!

New username, same ole Pat Macaluso!

_________________
Pat

Who was using a lathe to carve necks 200 years ago Michael? Did you see it in a book?

_________________
nigel

http://www.theluthierblog.com

Clay, I don't quite get it - do you have a pic with the router and cutter in action?

_________________
nigel

http://www.theluthierblog.com

Hi Nigel,
I will try to take some better pictures of my neck making process. I use a simple jig that the subbase of the router rides on which is basically a 2X8 that the neck blank is screwed to. I usually rout necks separate from pegheads and use a standard subbase on the router, but when the peghead is integral with the neck shaft I use the subbase pictured above. It lifts the base of the router above the "ears" of the peghead and allows the bit to shape the shaft and the transition area of the peghead. The picture below is the jig with a different router and normal subbase which may give you an idea of how things work.

I get it now. Very clever.

_________________
nigel

http://www.theluthierblog.com

Hi Nigel,
I glued up a blank and and used the router setup to "carve" it. I usually shape the neck and peghead separately (which I prefer) but this time glued the peghead on before routing. The heel block is intended for a spanish heel, for a gibson style heel it should be flush with the neck shaft. I used a hidden scarf joint to join the peghead to the neck because a don't like the line on the back of the peghead a typical scarf leaves with the thinner paddle head a steel string uses (with classicals you move the seam to the "chin" which doesn't look too bad.).
The first picture is the glued up blank.
The second picture is tapering the thickness of the neck shaft on the jointer as you might taper the leg of a hepplewhite table.
The third picture shows the blank mounted on the jig so the shaft is flush with the top.
The forth picture is the first side routed.
The last picture is the routed neck with the peghead trimmed to a typical shape.

If I did many integral pegheads one thing I would do is remake the subbase on that router by extending it beyond the base plate in the direction away from the bit. In order to rout the peghead area the router has to be turned so only 1/4 of the subbase is riding on the jig. With a 1 inch roundover it requires a steady hand to keep things balanced. A larger subbase extending out from behind the base plate might be a help.
I hate to waste wood so I use built up neck blanks. But I don't like to see a bunch of seams - a few are O.K.. I do a block heel (small piece of 12/4) and a 4 quarter or 5 quarter neck shaft. The peghead is generally from 4 quarter material also. By making the peghead separately I am able to use thinner stock for the neck and also cut it to close dimension using a tapering jig on the table saw. From a piece 4 1/2 inches wide I can get two neck blanks. The other thing I like about separate pegheads is much of the work (shaping, drilling tuner holes, cutting slots) can be done before assembly.
I am still refining my methods to make my necks require less hand work and be a little "greener" (and cheaper).

French romantic guitars. Perhaps the method was used elsewhere too. It's illustrated in the Sinier de Ridder book and looks as though a lathe was employed. There's just a very brief mention of a lathe being employed in relation to the neck. That and the illustration strongly suggests that is the method that was employed. Many of the necks were veneered over with ebony too. I suspect they have seen the tool marks perhaps on examples where the ebony has come off - that bit is my conjecture. How they attached the neck shaft to the heel too, which resulted in a long scarf joint. It all seems a bit odd if you are accustomed to doing it the more modern way.