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Ed Bond will not approve but it was fun to do. I’ve been using a full bolt on necks for many years now and wanted to improve my approach. I know what I’m doing is nothing new - it’s pretty hard to have an original idea in the luthier world, still I’m pleased with the outcome.

My most recent neck joint is the Gore/Gilet bolt on, bolt off. I like it very, very much. You are using good sense, in my book!

Lols. The best thing about my approval is that no one anywhere needs it.

Nice and clean. I learned about this neck joint in Charles Fox class. You have re inspired me to retry it again. Are you cutting your necks on Cnc? Where did you get the neck router jig?

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Hi David,

Portions of my necks are cut on my CNC. Everything between the volute and body joint are done by hand allowing for easier customization. I don't have to redraw each neck shaft and generate fresh g-code each time. The neck fixture is my own design and was also cut on my CNC.

Best, M

Michael--

One follow up regarding my first use of the Gore/Gilet bolt on, bolt off neck joint: Next time I build one, I think I will use threaded inserts in the neck extension, rather than T-nuts. Maybe a 6mm T-nut in Australia has a smaller footprint than a 1/4-20 T-nut here in the U.S.A., but I found that the T-nuts made things a bit crowded around the slot for the truss rod.

Don,

I always felt that the neck extension portion of the Gore joint was too husky for my liking and also never fancied threaded inserts. Instead it use a 10-32 t-nut (Brad type) that gets glued in place with some medium CA plus the glue from the fretboard install. The recess is .75” x .0625” with .25” center hole. Drops right in nice and snug. Maybe I’m missing the point on how strong it needs to actually be. I do like Gore’s brass bar insert but don’t own a chisel mortiser and I’m not sure it’s stronger than the barrel bolts I use.

Best, M

Michael,

Would you mind sharing a pic of the underside of the routing jig? I’m assuming the two holes are just to spy on the centerline to sanity check alignment but the pocket is creating the actual alignment on the body?


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Brad,

Yes, that’s exactly right. It’s cut from 1/2” pre-fin Europly using 1/4” aluminum rod for the index pins.

M

I think 10-32 will do fine. I don't think you need as much oomph on the neck extension as you do for the neck tenon.

I bought a used mortiser for around $100. It works fine. There seem to always be a few for sale on Facebook Marketplace. The brass bars are pretty stout!

I’ve used the 10-32s on my last 40 instrument without issue, so I agree they are adequate.

As the a mortiser - I’m sure I could find one though I’m not willing to give up the shop real estate.

Cheers -

I like it! I have been using a separate fretboard tenon but have seriously considered going to the tenon incorporated into the neck as you have done.

IMG_6113 by Terence Kennedy, on Flickr

IMG_1889 by Terence Kennedy, on Flickr

Couple of questions, obviously the upper bout has to be exactly coplanar with the neck angle for the fretboard to sit flat. How much movement do you get after string up and at say 6-12 months? If a minor neck reset tweak is needed to maintain proper saddle height is it hard to get the fretboard to sit flat against the upper bout since it’s no longer coplanar. Do you create any drop off in the fretboard extension?

The other thing is I didn’t notice any tenon reinforcements with the Cumpiano barrel nut technique. I had a couple of my early ones crack through the lower nut and always reinforce now.

Nice work!

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Hi Terence,

So far I’ve only needed to adjust the neck angle on one instrument. I had one I built 13yrs ago come in for a checkup and the action was exactly where it was when I built it - 5/64” and 3/64”. I think my design has proven to be very stable.

I’ve never found the need for the added tenon reinforcement. I’ve never had one fail in the 16yrs I’ve been building.

My old design looks quite similar to yours.

M

Thanks! Did your old design move more under tension than the new? In other words did the new design improve stability?

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I don’t know - this is my first go with the new design - the old design was rock solid.

Great design.
I really like the routing jig that is long enough for you to check alignment all the way down to the bridge area.
Thanks for the inspiration, and for the very clear illustrations.