Detachable Spanish Heel Dowel Neck Joint

[hoji]

Hey Ukulele builder friends!

I have decided to try something besides the Spanish Heel neck-body joint. It has worked well for me for my first dozen or so builds, except for the sanding and finishing. Hard to get in that corner! I want to try finishing the body and neck separately. I have tried a dovetail once before, but I had trouble with it, so I was thinking there must be some more "fool proof" method. Also, I don't want to use any metal parts. I came up with this idea. It uses dowels. I think it is basically a "detachable Spanish Joint".. the best of both, maybe?

The idea is that the dowel hole are drilled while the head block is attached to the neck. So when reassembled, it lines up perfectly again. See diagram below.

What do you think?

 

[Mike $]

That's how the StewMac kits are constructed. A butt joint with dowels. Hard to get the neck nice and straight, but it can be done. There are some free videos on the StewMac site for getting the neck set nicely.

 

[Tom Snape]

That should work fine for a ukulele, as long as things are lined up well. Here's a doweled joint on a ~50-year-old steel string guitar (lower end Japanese Morris) that I pulled apart for a neck reset. Worked fine there for most of that time.



I sometimes build with Spanish heel construction, and after I bend the sides I glue in the tail block and linings, then glue in a thin temporary patch across the gap where the heel will go. Then I'll sand the sides and do a few applications of shellac before completing the rest of the assembly. It doesn't completely solve the problem of final finishing around the heel, but it helps.

 

[hoji]

Thanks guys. I forgot to mention that I'm planning to also cut the little "shelf" or step in the headblock piece, as would be done in the Spanish style. In this case, jist shaving off the top of the headblock.

So, with the neck temporarily attached, I will glue the head block to the soundboard. Since this procedure will be using a center line the length of the neck plus body as a reference, it should ensure that the headblock is in the right place. So when the neck is re attached it will be correctly positioned as well, as would be the case with a traditional Spanish heel build. At least that is my theory. I plan to try this next week and will report back with results and photos.

 

[BuzzBD]

I think you may have considerable difficulty maintaining the dowel alignment after you cut the heel block off the neck and then sand their adjoining sides. Anything other than perfect alignment will mean that the dowels fit will be compromised. And remember you have to maintain the neck angle at the same time.

 

[hoji]

I think you may have considerable difficulty maintaining the dowel alignment after you cut the heel block off the neck and then sand their adjoining sides. Anything other than perfect alignment will mean that the dowels fit will be compromised. And remember you have to maintain the neck angle at the same time.

Hm... Yeah, you are right.

Thinking about this more, maybe this isnt such a great idea. I think dovetail is really where I want to go.

I think I can use this same principle though. The principle of ensuring the fit and alignment ahead of time. Make the headblock and mortice to fit the neck tennon before building the body. Glue down the headblock to the soundboard Spanish style, with the neck attached, for alignment, as if one piece. ( Instead of cutting the dovetail mortice after building the body. ) This way I get as many tries as needed to get the joint right.

Going to think this through a bit more.

 

[Red Cliff]

Just use a bolt on neck.

 

[dofthesea]

Why reinvent the wheel. Just put in inserts with a neck bolt. Easy peasy. Really easy to do.

 

[BuzzBD]

I have been working on this issue for forty years now, and I have done them all many times. My criteria is the method has to be relatively fast and strong, and also be reversible for repair. Most of my necks today are a combination of bolt / glue, using a brass threaded insert in the neck for the bolt. In reality, the bolt mostly serves as the clamping device. You could substitute a lag screw for the bolt and insert, and remove the lag screw after gluing the neck on. My next favorite method is the standard dovetail. I have the StewMac templates and bit. The heel block and neck are always cut together for best fit. The secret to making a good dovetail joint is being very methodical in fitting it. You first adjust the fit so the neck aligns with the center line of the body. Then you adjust the neck angle for the correct action (while maintaining the center line). And then adjust the fit to be flush with the top and match the sides. If you are not systematical in your approach, you can be forever chasing your tail. Using a small sanding block with the same angle as your dovetail really helps as well as liberal use of chalk. As with everything, you get better with practice and if necessary it is not a crime to use shims.
Brad

 

[hoji]

I have been working on this issue for forty years now, and I have done them all many times. My criteria is the method has to be relatively fast and strong, and also be reversible for repair. Most of my necks today are a combination of bolt / glue, using a brass threaded insert in the neck for the bolt. In reality, the bolt mostly serves as the clamping device. You could substitute a lag screw for the bolt and insert, and remove the lag screw after gluing the neck on. My next favorite method is the standard dovetail. I have the StewMac templates and bit. The heel block and neck are always cut together for best fit. The secret to making a good dovetail joint is being very methodical in fitting it. You first adjust the fit so the neck aligns with the center line of the body. Then you adjust the neck angle for the correct action (while maintaining the center line). And then adjust the fit to be flush with the top and match the sides. If you are not systematical in your approach, you can be forever chasing your tail. Using a small sanding block with the same angle as your dovetail really helps as well as liberal use of chalk. As with everything, you get better with practice and if necessary it is not a crime to use shims.
Brad

Brad, thanks ... Good advice. What exactly do you mean by "The heel block and neck are always cut together for best fit." ?

 

[BuzzBD]

With the StewMac dovetail templates, one template is for cutting the dovetail slot in the heel block/ body and the other is for cutting the dovetail in the base of the neck. You have two choices, you can cut the dovetail slot in the assembled body or you can cut the slot in just the heel block itself and assemble the body later. I have learned through bitter experience that while routers are marvelous tools, if something goes wrong, they can destroy things in an instant. So I always plan to use them as early as possible in the construction process. Thus I route the dovetail in the neck and then route a matching neck block to assemble in the body later. The templates are designed to cut dovetails for guitars down to ukulele, so the length of the dovetail needs to match.

 

[hoji]

With the StewMac dovetail templates, one template is for cutting the dovetail slot in the heel block/ body and the other is for cutting the dovetail in the base of the neck. You have two choices, you can cut the dovetail slot in the assembled body or you can cut the slot in just the heel block itself and assemble the body later. I have learned through bitter experience that while routers are marvelous tools, if something goes wrong, they can destroy things in an instant. So I always plan to use them as early as possible in the construction process. Thus I route the dovetail in the neck and then route a matching neck block to assemble in the body later. The templates are designed to cut dovetails for guitars down to ukulele, so the length of the dovetail needs to match.

Got it. This jives with what I was thinking... Make and route the neck block ahead of time and make sure it fits the neck tennon just right. Can make multiple neck blocks if imperfect, no worries. Sounds much better than routing or cutting the mortice into the finished body.

 

[BuzzBD]

Got it. This jives with what I was thinking... Make and route the neck block ahead of time and make sure it fits the neck tennon just right. Can make multiple neck blocks if imperfect, no worries. Sounds much better than routing or cutting the mortice into the finished body.

There is a little bit of fudging things because the added thickness of the sides at the dovetail effect the fit.

 

[sequoia]

I have learned through bitter experience that while routers are marvelous tools, if something goes wrong, they can destroy things in an instant.

I shudder to ask what bitter experiences you have had, but I can imagine. (Shudder). I used to long ago hold the the body of the uke in my arms when I was routing binding channels when one day all of a sudden, and I mean in a thousands of a second, the router hit a bit of hard wood, and flew out of my hand uncontrollably. Nothing damaged other than my underwear fortunately. Now I use a cradle and I stand back.

Edit: Sorry don't mean to hijack this interesting thread and go to the horrors of routers.

 

[Island Jim]

I can appreciate a well fitted dovetail joint but I feel a straight shouldered mortise and tenon joint is a good substitute. I think when other posters have suggested a bolt on neck they are talking about a mortise and tenon with a mechanical fastener!

 

[Timbuck]

I've said this before ...."you can set up a dovetail just like a Spanish heel set up, build the uke with a dry neck joint and remove the neck later for finishing.
12BEA87C-1338-4DA0-9150-C12444AD5718 by Ken Timms,

 

[printer2]

I just reglued a mandolin neck onto the body, it had the three dowels to fix the position of the neck. Make a jig to drill the holes, get some scrap lumber and practice to see if you can get the alignment right. (I took pieces of a 2x4 and practiced doing about 6-7 dovetail joints to get the hang of it)

 

[hoji]

Gonna try the Timms method.

 

[Timbuck]

Gonna try the Timms method.

Brave man ... first time I tried it was with the ancient inside mould method. ..It dosn't have to be a dovetail it will work with a bolt on as long as you don't glue it.

 

[Beau Hannam Ukuleles]

OR....just use one (or 2) metal bolt(s). No matter how hard i try to line the holes up, I get a mismatch so have to elongate the bolt hole into an egg shape so the top of the neck is on the same plane as the top of the upper bout.

Also, Bolts are traditional method too. Or use a large nail like Stradivari did in his violins......