Question for Tom Ellis

[Mandoborg]

Tom, i just spent a few minutes on the construction section of your web-site, nice site btw , and was intrigued by your neck joint. It seems to be the Siminoff 'V' mortise, but somehow you have the concave sides so it looks like the traditional dovetail when together. Do you have any pictures of how you do this, or maybe just explain how it's done ? I don't think i've ever seen anything like that ! Do you pin the joint at all because it seems to fit really nice as cut !!

Thanks,
Jim Combra


P.S.
Are you coming to Newport again this summer http://www.mandolincafe.net/iB_html/non-cgi/emoticons/rock.gif

[ellisppi]

Jim,
You're right , its a curved side mortise & tenon joint. It requires custom cutter bits and a complex jig but it makes a nice joint, 100% fit. I put a screw diagonally down from the back of the truss rod barrel nut into the lower part of the headblock for dry fitting and sanding the back of the heel, after the body is bound, the neck is glued in with the screw as a clamp, then I remove the screw and replace with a dowel. The joint itself does not require any kind of dowel or screw for strength. Sorry no pics of this operation.

[testore]

I do my necks without a dove tail also, but I don't have any fancy jigs or anything. Since my background is violins I have only used the violin neck joint method. For a mando that neck joint is so deep that there is an incredible amount of glueing surface when fitted correctly and it is VERY strong. I have used pins and dowels too but I'm doing some without them too. I'm not 100% sure of what you mean by "concave sides" but I think I know what you're talking about. Since the neck foot is tapered(from fingerboard to the button width) there's the illusion of a arc when viewed from the side. I don't think you can tell if someone has used a traditional dove tail or not can you?Also, I use hide glue always. That stuff is so unbelievably strong. I know of a cello made in 1809(James and Henry Banks) with it's original neck set. It was only set as deep as the ribs are thick,(1.7mm) in other words,the neck foot doesn't go into the upper block at all. This neck didn't need anything. The pitch was perfect and there wasn't a loose spot anywhere. 200 year old hide glue still working that well with almost no glueing surface!!! That settled it for me when I saw that. I wonder what everyone is using for their neck joints. I did see one Gilchrist in need of a reset. Does anyone have any idea if white glue could be the reason? What about Loar necks? I'm assuming that titebond type glues weren't in use in the early 20's? Is there a relation between glues and the need for neck resets? It's difficult, I know, to determine if the necks need resetting because of bad glue or poor fitting but does anyone have a lot of experience with this?
Gary

[Michael Lewis]

Gary, the instruments of the 20s were nearly if not all assembled with hide glue. A poorly fitted dovetail can cause the need for a reset, but a well fitted dovetail won't give up or move. If the instrument needs a reset when assembled with hide glue it will usually be from the deformation due to string tension. Not sure what a Gilchrist is assembled with, but if it is modern glue heat alone can soften the glue and allow it to creep out of alignment.

I reset the neck of a '77 Gibson that had held up well for many years until it got left in a car in Los Angeles during one summer. Obviously not hide glue, and not a dovetail either. There is good reason to use many of the old ways.

[Mandoborg]

That sounds pretty dang slick Mr. Ellis !!! Thanks for the prompt answer, i had a feeling there was the dreaded ' special cutters' in there somewhere !!!
Thanks to Gary and Michael as well, good information there . Hide glue is like a gift from the heavens, it not only holds well, the stuff smells so dang good i'd like to keep a jar simmering in my shop at all times as an air freshener, not to mention it looks so good you just want to put it on a hot dog !!!! Have a great weekend
http://www.mandolincafe.net/iB_html/non-cgi/emoticons/biggrin.gif

Thanks again guys !!!

Jim Combra

[testore]

Jim,
Just add sugar,food coloring,chill and serve.