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So I finally got to working on the neck tenon. Following Cumpiano’s new and improved method. First thing I realized was that I needed a 10mm drill bit, to drill the holes for the barrels. You would not believe how hard it is to find one around here. Had to go to Lee Valley and pay $30 for one. Then I put it in my drill press, and quickly realized that even with the stage at its lowest point, the neck heel would not fit under the bit. In hindsight, I just realized I could have cut off one of the tenon cheeks and it would probably have fit. As it was, I used a hand-held drill for the job. I was careful, and didn’t go too far wrong, but the problem happened when I drilled the holes for the bolts. Way too low. I guess I wasn’t careful enough marking the lines. So today I went and got a hardwood dowel to fill the holes and re-drill them. Problem solved, tenon cut, pics below.

Hi Colleen, forgive me if I'm wrong but the improved Cumpiano tenon, as I understand it has side reinforcements as shown in the photo. There have been many guitars made without the reinforcement so don't worry, or maybe it is your intention to do so anyway. Just thought I'd mention it. Good luck. Mike

True, and I may add the reinforcements, but that might be more trouble than it’s worth. I’m working with hand tools mainly, I don’t have a table saw, so I cut the tenon with a Japanese pull saw. I mainly just wanted to do a bit of show/tell about my process, and how I solved a resulting issue. More to come. Thinking about buying a spindle sander for shaping work.

I'm doing the same job now. I screwed up by rounding the corners on the wrong side - side facing the neck. I may take some of the block off to get a little more glueing surface or redo it. If I redo it, it will be neck block #3 for this guitar (J-185).

I think you should consider the side reinforcements. There have been threads here I believe about cracks occurring using this method and it would be no fun to have to redo this a year or so from now. I would at least suggest flooding the holes with thin CA to strengthen them up a bit.

Good luck!

I posted this over in MIMF as well.

Although putting the dowel nuts crosswise like that usually works, it can be a problem. When there is pressure on the bolt it pulls the nut down against the end grain wood of the tenon. If the nut is not a very tight fit the pressure is concentrated along a line toward the nut, and there can be significant sideways pressure. If the nut is too tight, and the neck sustains a blow of some sort, it can split.

This happened to one of my students when we started using cross dowel nuts. He had bolted the neck on his guitar and when he picked it up from the bench he hit the head against a low beam on the ceiling. The heel split across at the upper nut and the body of the guitar fell to the floor. At least one other local maker has had that happen that I know of.

Since then I've been drilling the holes for the cross dowels on the center line of the neck, perpendicular to the fingerboard plane. That way, if a split gets started the assembly 'fails well'; the two halves are retained in the mortice and the neck can't fall off.

Hardware is always a stress riser in wood construction, and you have to design for that. The FAA guidelines are that any hardware, such as the bolts that hold a propeller on, should be a force fit into the holes. This distributes the stress across the whole width of the hole, and, at least in theory, produces a shear load at the edges of the hole rather than a sideways splitting force. I usually try to set the dowel nuts in some slow setting CA to help distribute the load. Avoid over tightening the bolts.

Thanks, I think I will. I’ll clean up the sides of the tenon on my bandsaw (which I now realize I coulda, shoulda used instead of the pull saw). Thing is, my workbench is in my basement, but my power tools are in the (detached) garage, so it’s easy to forget about them…

The problem with new innovations is not that they don't work, it is that they usually assume that you have a machine shop, because that is the modern way. I don't. I HAVE done a bolt on neck, for a Stauffer guitar. 90 pounds of string, not 130, but it was pretty simple; basically a dovetail that is bolted tight. I am building one with an electric guitar type bolt on, but simple, with hand cut and fit joints. The bolt on necks I see are geared toward a fixture type shop. Heavy investment up front in tooling.

I don't make a form! Laminated neck that makes a truss rod slot. Hand bent sides. Some people like all the tooling. Everyone is different.

What I find interesting is that guitar people all want easy to move/replace necks, but the body is wrapped with binding! Internal repairs are not easy. Violin makers have a dovetail neck and frown on any mention of a bolt on (Joseph Curtin does make a bolt on) but they leave overhangs on the belly and back so they can routinely pop the belly off, (rarely the back) to repair cracks and replace/reglue bass bars. Most old (hundreds of years old) violins have new necks, and they will often even graft on the original scroll. A lot of work. But they wouldn't do a bolt on!

Ken Parker seems to make his so the neck is easy, and internal repairs are easy. But his, and Joseph Curtin's neck designs are beyond my saw and chisel shop. But with no binding, you just have easy to do purfling, and inlays/rosettes.

Anyway, It is just food for thought. Think about what you can do in your shop, and stick with that. If you really like bolt on necks, maybe you need some fixtures, and a bigger drill press/mill.

I really DO like the way that you are pressing forward THROUGH adversity. Well done. Making things, especially for the first time is all about fixing, and changing things. At least for me it is.

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Interesting points about the differences between guitars and violins. I guess my take is that violins are generally expected to last WAY longer than most guitars will, so repairs are expected, whereas anything other than a really high-end guitar wouldn’t generally be worth doing internal repairs on. Dunno.

Thanks for the compliment. I definitely need a bigger drill press (and a bunch of other stuff).

Already got a line on a bigger drill press…

Got myself a “real” drill press yesterday. $250, used. Works great! No more using a hand drill when a drill press is needed…

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Gluing on the headstock veneer. Used a couple off-cuts from the back, book matched.

I have a similar radial drill press. They are very handy for wood work and give you a lot of reach and also allow you to do angle boring. One of the first things you may want to do is make a sacrificial wooden auxiliary table and attach it on top of the metal one. It will provide a means to screw fixtures down, save your drill bits when through boring, And when made larger than the metal table provide more support for the work.
Radial presses generally aren't as "stiff" as conventional drill presses, so aren't favored by metal workers, but work o.k. for milling softer and thinner metals.

Headstock veneer done. Tomorrow: rough-cutting the headstock. Also, I got my circle-cutting jig from Stew-Mac, so I’ll practice with that on some scrap before touching my soundboard with it.

Great idea! Yes, I just realized this morning the value of having a radial press, it will allow me to easily drill a hole in my work board for the pin for the circle jig.

Sink cutouts make a good drill press table extension. You can shim it up with small wedges and adjust it until it's dead perpendicular to the quill. Use a length of coat hanger wire bent in a 'Z' with one end in the chuck to check that.

I get a lot of use out of my old Wagner 'Safety Planer', taking sides and necks to thickness, roughing arches, and so on. If it's sharp, and the table is really perpendicular, you can make half millimeter veneer with one. Keep in mind that 'safety' used in reference to any power tool is aspirational...

Thanks, Alan. I also have the Wagner Safe-T Planer, and used it to thickness the headstock veneer but not to final thickness. Once I get the headstock roughed out, I plan to bring it to final thickness with the orbital sander and scraper.

On the subject of cutting out the headstock, I’ve run into something I can’t figure out.

I’m using the template from the Cumpiano book. My plan is to cut the headstock on the bandsaw, from the back (i.e. with the headstock flat on the saw table). My conundrum is, where do I place the template? My sense is that the bottom of the template should line up with where the angle begins on the face side (i.e. at the nut), but this means that on the back, the bottom of the template will be across the scarf joint from the top. Is this correct? If I line up the bottom of the template with the scarf joint on the back, I think that’ll put the headstock too “high”. Help?

I think I’ve answered my own question. The headstock needs to meet up with the neck at the nut, so of course it’s going to traverse the scarf joint.

Colleen--

Another way of doing this (if you haven't already) is to put the template or markings on the front of the peghead, and put the peghead on top of a block of wood that acts like a booster seat. Then you can cut the shape out with the peghead facing up, and there is room for the rest of the neck to not knock against the bandsaw table. You have to clean this cut up with other tools regardless. Just a suggestion. If you have a small bandsaw, this might not work well.

I miss the big press at Greenridge, and had been making due with a garage sale bench-top until the Tekna comes back into stock, but I may not be able to wait much longer. How do you like that model?

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I’ve only used it once so far, but it’s great! So much nicer than my little bench press. All kinds of space.

I’ve also determined that today I will buy a combination belt/spindle sander, which I’ll get all kinds of use out of.

Colleen, I've had one of the Ridgid spindle sanders in my shop for 15yrs. I could have updated anytime in the last 10 years if I wanted to but it just works so well I don't need to. The belt sander attachment is useful but I don't put it on much since I have 2 other belt/disc sander combos.

https://www.homedepot.com/p/RIDGID-Oscillating-Edge-Belt-Spindle-Sander-EB4424/202459151?mtc=SHOPPING-BF-CDP-BNG-D25T-025_009_PORT_POWER-NA-NA-NA-SMART-NA-NA-NA-NA-NBR-NA-NA-NA-PortablePower&cm_mmc=SHOPPING-BF-CDP-BNG-D25T-025_009_PORT_POWER-NA-NA-NA-SMART-NA-NA-NA-NA-NBR-NA-NA-NA-PortablePower-71700000086134208-58700007341211180-92700065813629939&msclkid=6e7e2c50ce851710f5ae4f5ed2700ff7&gclid=6e7e2c50ce851710f5ae4f5ed2700ff7&gclsrc=3p.ds

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