Siminoff V-joint versus Dovetail joint?

[Nick Gellie]

Has anyone had much experience with Siminoff's V-joint as opposed to the traditional dovetail? Anyone care to advance the pros and cons of each option?

Thanks

[testore]

As a violin maker I do the traditional violin style neck set.(Siminoff) it is easier to fit and I think there is more glueing surface.

[juneman]

Hi NICK, like a lot of builders when i started some fifteen years ago SIMINOFF was the go to book on building mandolins. The dovetail joint was always intimidating,at least for me. I have used the siminoff joint almost exclusively up until going full time as a builder about two years ago. Now i cut my own dovetail joint and wonder why i took so long to change. I think the dovetail is easier and allows for more adjustment. I dont use a taper,i prefer a straight dovetail. The straight dovetail allows me to easily adjust for bridge height on each build. One thing i started doing lately is to not cover the heel with the back,i just like the look and usually match the cap to the neck strip or pick guard and peghead. Another thing i am working on changing is making my heel cap smaller on future builds. I made a template for my dovetails out of plastic pick guard stock. I cut both the neck block and the neck on my band saw set up with an 1/8 inch blade. I made a small jig that holds the neck at the proper angle. With my set up it takes me about an hour to cut both and get the fit i want. Hope that helps,for me the again i like the idea of having the adjustment from the straight dovetail.

walter JUNE mandolins and guitars

[Bill Snyder]

HERE is a thread I started on that joint ten years ago that got several responses.

[sunburst]

A dovetail joint is not an easy thing to learn and master, especially with no one to show you how and help you through the process of learning and creating it, and especially for people coming to instrument building with little or no wood working experience, and the Siminoff book was written in anticipation of those people building a mandolin. I think it was a good decision to include the tapered, doweled, mortise and tenon joint in the book. The dovetail joint is also mentioned in the book, and it might have been nice if a tutorial on the joint had been included as an option for the likes of me, who built my first (A-style) mandolin using the book as a guide, but used a dovetail joint (and any other changes I saw fit). I'm not an editor nor an author, though, and that would have made the book longer and it would have taken more time, and it would undoubtedly have been a source of even more frustration for those deciding to learn tapered dovetails while trying to learn instrument building. (Scrolls and points are distraction enough from trying to learn instrument building.)
All in all, the joint in the Siminoff book was chosen to help the inexperienced student luthier avoid the pitfalls of learning a tapered dovetail mandolin neck joint while going through the process of building a first instrument.

I prefer a tapered dovetail joint for a variety of reasons, including tradition, but mostly I like the elegant, self-clamping, solid way a dovetail joint comes together into a mechanical, reversible joint that will hold without glue*. There are more neck joint possibilities than these two, including hardware joints ("bolt on"), and many of them do the job of holding the neck onto the body just fine.

*(I can tell you from experience in my repair business that both the doweled mortise and tenon and the dovetail can be reversed when left in a hot car in summertime, but the dovetail is easier to repair. A dovetail needs glue if it is to withstand the constant handling and temperature and humidity changes to which an instrument is subjected.)

[juneman]

Hi i dont want to take the thread off course but i have a question. John, do you or have you seen any reasons not to do a proper fitting,tight straight dove tail. You have seen way more repair work and failed joints than i ever will. I know abuse can affect any joint but under normal care i cant see a proper fitting straight dovetail failing. Could it fail?? Like i said i my earlier post i like the idea of the adjustment factor.

walter

[sunburst]

Walter, Many years ago, I built an F-5 made of cherry wood, did not stain it, so everything had to look just so. On the last sanding before finishing, I ruined the neck. (Actually I ruined the neck earlier when I set the truss rod too deep, not when I sanded through into the truss rod channel... but I learned from that!) Anyway, I had to remove the neck and replace it. I used steam and the assistance of a couple of other guys working in the shop (when I worked "at the factory"), and finally after much steam, much force, and much sweat, managed to remove the neck from the mandolin without doing any damage. That dovetail was hard to release!
I made a new cherry neck, fit the dovetail again. Actually, the second one went better and the fit was equally good if not better than the one that was so hard to remove.
Some years later, I got a call from someone who owned that mandolin. He had accidentally left it in the truck after a gig and forgot about it the next day, so it spent the day in the truck in summertime. The neck neck joint failed and the neck came partly out. When he brought it in for repair, I took the neck the rest of the way out and cleaned up the old glue. The joint still fit! There was nothing I could do to improve the fit, so I just cleaned it up and re-glued it. From that, I learned that enough heat can reverse nearly any glue joint if it is under stress, like string tension. A joint that took me, steam, and two assistants to reverse, popped loose in a hot truck with no effort from anyone other than string tension.
So now I've set the neck in that mandolin three times!
Before that, I couldn't see a properly fit tapered dovetail failing, but it did, and I see no reason why a straight dovetail would fare any better. You said "under normal care", however, and hot car interiors aren't "normal care". I expect any well designed, well fit joint in good materials to hold up fine under normal care.

[fscotte]

Wood fails all the time. Just put some in a fire.

[MysTiK PiKn]

HERE is a thread I started on that joint ten years ago that got several responses.

Bill, thanks much, for the link. A great read.

[Nick Gellie]

Thanks to you all for the great posts. They have clarified the pros and cons of each type of neck joint.

[Larry Simonson]

Regarding the choice of either straight or tapered dovetail neck joints, it seems to me that the tapered version would offer easier disassembly. My reasoning is that disassembly requires lifting the neck up from the neck block and a tapered joint gets looser as the neck is raised, whereas a straight joint does not. This is akin to molds for parts being tapered slightly for easier part removal.

[Bill Snyder]

Both of the joints being discussed are tapered.

[Larry Simonson]

Bill, I was referring to Juneman's post above where he wrote "have you seen any reasons not to do a proper fitting,tight straight dove tail" (as opposed to a tapered dove tail)?

I believe this tread supports the argument that several joints are suitable for a stable neck to body connection, so it seems to me that ease of disassembly should be included in a "what is the best joint discussion".

[HoGo]

Regarding the choice of either straight or tapered dovetail neck joints, it seems to me that the tapered version would offer easier disassembly. My reasoning is that disassembly requires lifting the neck up from the neck block and a tapered joint gets looser as the neck is raised, whereas a straight joint does not. This is akin to molds for parts being tapered slightly for easier part removal.

Fully agree with this. Straight dovetails can sometimes be PITA to disassemble. Even when you inject steam and glue is soft but when neck is flatsawn and grain of neck block goes across the neck can swell from the moisture more than the dovetail in the body and bind really tightly. You have to do it really quickly, heat just enough to soften the glue and remove before the wood takes too much moisture. Tapered dovetail needs just 1/8-1/4" move up and it's free.