Neck joint again

[Larry Simonson]

I am in process of building #1 and just glued in the neck using the Siminoff method. I have not however drilled for and glued in any dowels as yet because I am bothered about its ultimate strength and/or dissembleability. I have been following threads on this topic for a few years and base my fears on what has been written on this forum, however I feel that the absence of any reported Siminoff joint failures speaks well for his joint. Obviously it is too late for me to consider a dovetail, I had decided early on that I was not up to cutting one of those yet. Instead of using the dowels, I am considering installing a wood screw thru the end block into the heel thinking that it would provide a significant element of strength along with making it much easier to take apart in the years to come. I'd appreciate any advice.

[billhay4]

Tricky issue. You are correct that a dowel creates a removal problem. I've used a screw but am not confident it really does much.
I think with Number 1, I'd use a dowel IF you are confident the neck is exactly where you want it now. In the future, I'd use a dovetail.
FWIW,
Bill

[Ken]

I've used the Siminoff method for about 27 years. No joint failures, including dropped mandolins and ones found floating after a flood. Also kept one under the rear seat of my van for many years, no problems. Disassembly is an issue with the dowels, never had to do it yet, but I figure it would mean taking the back off and drilling out the dowels and then using steam. It was suggested in a much earlier thread here on the cafe that the dowels are really not necessary, especially once you glue the back on. I'm inclined to believe that, but haven't tried it myself. I don't think the screw is necessary.
Ken

[Mario Proulx]

I use that joint also, and tried it dry, and the neck simply slips out(upward), so it should be removable by the same steam method as a dovetail. It -is-, in fact, a large dovetail.

[sunburst]

I can testify that that joint will release in the trunk of a hot car, which is one of the most common ways that I see owners removing the necks of their mandolins.

[Mario Proulx]

If it released in a trunk, it wasn't done correctly in the first place. It's a purely mechanical joint, same as a dovetail(because, it -is- a dovetail), so the glue softening in heat shouldn't affect it any more than it would a 'traditional' dovetail.

[sunburst]

I've put dovetails back together that came apart in the trunk of a hot car too (properly fit too - one of them was mine!). There aren't many joints that the hot car trunk can't reverse!

[Michael Lewis]

Newton - if your neck joint is fairly well fitted mortise and tenon and glued well it should hold without a screw or the dowels. Just don't get it too hot. Gibson used a straight mortise and tenon in the 70s, no dowels, and what resembles glue gun glue. As long as they are not left in a car in the middle of summer the joint worked well enough.

I never saw a need for the dowels, and if you are going to use screws why don't you just bolt the necks on?

[Stephanie Reiser]

I never understood why people don't bolt-on mandolin necks; I do that on guitars, along with mortice and tenon joinery. Probably because on F-hole bodys it is difficult to get the wrench in there unless you wait till afterward to glue the back on. I guess tradition plays a part in it. So, I labor along and hand cut tapered dovetails, just like the antique Gibsons.
I have a friend/builder who uses the Siminoff method to a T, and he swears by it. He even built the jig. I admire how fast he makes that joint, but I lumber along with my sandpaper and chisels and 1/8" bandsaw blade, cutting that difficult joint.

[Rob Grant]

So here's a question... why would anyone want to remove the neck on a mandolin? I use the Siminoff method because I set the neck up right the first time. Damned if I'm going to make any adjustments in the future. With Siminoff's method, the neck and headblock literally become one piece. To insure they remain one piece I use epoxy for the joint.

I mean, if you really want to remove a neck fixed with this method cut it out with a fine razor saw like is often done with violins. I've never had a problem with this method of neck attachment. I have repaired a few "crook" dovetail joints on other mandolins. One case involved shrinkage of the timber components of the original dovetail joint which cause the neck to partially separate under string load.

[sunburst]

I never understood why people don't bolt-on mandolin necks...I guess tradition plays a part in it.

For me it does, but mostly I use a dovetail joint for three reasons;

-I like a dovetail joint. It is so elegant in the way it holds and resists tension, leverage and torque, the way it is self-tightening and clamps itself when you glue it, the way it lends itself to production processes or to simple hand tools to construct, and so forth. It has an ancient simple elegance that appeals to me.

-I don't want to add the mass of neck attachment hardware (bolts of some sort) to my mandolins.

-I enjoy the challenge of fitting a dovetail neck, and since the oft-mentioned trade off of choosing a low paying career like lutherie is; "I'm doing what I enjoy", why not use a joint I enjoy doing?

[sunburst]

So here's a question... why would anyone want to remove the neck on a mandolin?

A few examples:

-Someone left it in the car and the neck joint has moved and the geometry is no longer correct.
-The neck is so badly damaged that it needs to be replaced.
-The neck was poorly set originally.
-The head block has cracked and needs to be repaired.

[Larry Simonson]

Thanks for all the advice. I read them all with great interest and hope the discussion will continue. I will keep batting this around until i get the back ready for attaching and then I will have to choose.

[Mario Proulx]

John, have you ever tried the Siminoff joint? It's also very elegant in its simplicity, it also is an age old joint, likely much older than dovetails, as pinned M&T joints go back to at least the pyramids.

In use, it's much more solid and massive, having at least 6 times more glue surface area. and if we cut the area with the same taper as the fretboard, which i do, it's also a self tightening dovetail. And when we drill for the pins, if we do so at the same angle as the neck, we can lift the neck right out, so it would release just like a little dovetail would. And a great neck to body fit is a given, every time.

I've used both the little dovetail and the alternative here, and now only use this one. But I don't go about belittling those who choose a "traditional" dovetail, or even a bolted neck.

[sunburst]

I've been trying to remember if I've used the Siminoff joint, and I can't remember for sure. I know I considered using it on my first couple of mandolins, but I might have decided to try a dovetail just to see if I could do it on a curved head block like a mandolin (as opposed to one like a guitar).
Anyway, I've been fitting dovetails fairly regularly for 20 or so years and I like them, so I'll most likely stick with them.

As I've said before, I don't think the type of neck joint is important, but I think the quality of the joint is important. Good quality dovetail joints, mortise and tenon joints, doweled mortise and tenons, hardware joints, and even epoxy butt joint has proven satisfactory in use, I just like dovetails.

[Rob Grant]

John wrote:
"I don't think the type of neck joint is important, but I think the quality of the joint is important."

Well said. I respect John's love affair with the classic dovetail joint. The dovetail joint is an elegant bit of joinery which takes a craftman to properly execute. I just feel, for me, that that bit of time expended in creating the joint is better spent on some other part of the instrument.

The original question from Newtonamic also mentions whether or not to use the wood screw... I wouldn't. The screw is the addition of a slight bit of excess weight that doesn't really improve the joint's strength. The screw also acts as a hidden pitfall for any future luthier that may want to remove the neck.

[Bernie Daniel]

Sunburst:I've put dovetails back together that came apart in the trunk of a hot car too (properly fit too - one of them was mine!). There aren't many joints that the hot car trunk can't reverse!

Thanks! I've always wonder how you get a neck off. Just putting it in the my car's trunk while I beat the heat with a swim and a cold beer at the pool seems like a really easy deal!

[Jim Hilburn]

While Roger said in his first book that using the mortise and dowel joint resulted in the same look as a dovetail, I have to disagree.
This look (Loar from Mandolin Archive) is only achievable with a dovetail. It's more elegant and blends the neck into the heel binding nicely.
I know there's not a lot of instruction on dovetailing out there but it seems to me if your going to make a mandolin it would be something you would like to know.

[sunburst]

Jim, I agree that the mortise and tenon, done according the the method in the Siminoff book gives a neck heel that looks different from the Loars, but a dovetail isn't the only way to achieve that look. Curving the sides of the mortise and tenon, a hardware joint, or an epoxy butt joint can give you that look.

[Jim Hilburn]

I'd hate to be the guy trying to fit a curved mortise joint. You think a dovetail is hard? The whole point of the mortise is to simplify the process.
Epoxy? Not me.

[sunburst]

Me neither, but it works.
I'm pretty sure Tom Ellis uses a curved mortise joint, of coarse he has CNCs to cut the parts. It's not a joint for a hobby builder.

[Jim Hilburn]

John, most of what guys like you and I post is meant to be helpful to the guys who are just jumping in or at least small shop level guys. The CNC guys don't count, at least when they're doing things that are otherwise impossible for us bandsaw-drillpress-chisel guys.
When Roger first printed "How to Construct a Bluegrass Mandolin" in about
'76 it wasn't a guide to make a replica Loar, but instead a guide to the hobbiest looking for a very challenging project, which was intended to get you close and end up with a playable instrument. The neck joint was a compromise because a dovetail was so much more complex.
But most people who are interested in building now have so much more access to tools, materials and know-how. Something like the dovetail joint isn't quite as mysterious.

[Jim Hilburn]

I jumped into this thread because I just happened to be doing a dovetail today. I guess it could be considered a hijack.
Here is how I go about getting the heel taper once I've cut the joint to size. If anyone has any other good tips I'm all eyes.
My occillating table sander works well for this except it's hard to get a consistently smooth contour. Generally with this tool the faster you can make a pass the better, but you still have to be aware that your not removing wood from either the fingerboard width or the heel button.
Once I get it close this modified 3M hard rubber hand sander used upside down allows for safe proper shaping.

[sunburst]

I never thought of using the spindle sander to shape the neck heel, I think I'll give it a try. I usually use a flex shaft rotary sander, but a lot of the dust from that goes in the air... almost all the dust from the spindle sander goes in the dust collector. Good tip!

[Mario Proulx]

All the curves 'trick' the eye, I guess. Not as pronounced, but definitely not as straight as we'd expect.