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erich@muttcrew.net
07-27-2010, 08:43 AM
OK, our walnut/cherry uke is ready for the final steps.

I used a bolt-on neck, although there won't be a way of unbolting it withouth removing the back. Anyway the neck joint fits nicely but there's one problem. There is a very slight gap between the soundboard and the fretboard - I'm guessing a postcard might fit in between, maybe not quite. (Sorry, my thickness gauge got left behind on our tour in May - it doubles as a nut slotting file and we had a couple instruments on board that still needed a bit of coaxing in the action department.)

OK, so my question is whether it would be better to just bolt 'er up and slap the back on? Or would it be wiser to shim the gap and glue the fretboard onto the soundboard? Any thoughts would be appreciated.

Thanks.

SweetWaterBlue
07-27-2010, 08:49 AM
Rick Turner builds the Compass Rose that way on purpose to let the soundboard vibrate more, so maybe you ought to just leave it and call it a "feature," unless you think the fretboard is too thin to support any pressure. I used to work for a software company. They always told me that some new error that was discovered was a new feature lol. At the very least, I guess you could say it was an experimental model.

Moore Bettah Ukuleles
07-27-2010, 09:01 AM
Rick Turner builds the Compass Rose that way on purpose to let the soundboard vibrate more, so maybe you ought to just leave it and call it a "feature,".

Yes, Rick Turner incorporates a floating fret board extension but it is reinforced with carbon fiber; it's not going to be moving around a lot. Personally, I want the upper bout to be as stiff as possible and I'd encourage you to eliminate the gap and glue it down. A shim would remedy the problem but a neck reset would be better. I'm not sure why you can't simply loosen the bolt through the sound hole and reset it......

fahrner
07-27-2010, 09:13 AM
Rick Turner builds the Compass Rose that way on purpose to let the soundboard vibrate more, so maybe you ought to just leave it and call it a "feature," unless you think the fretboard is too thin to support any pressure. I used to work for a software company. They always told me that some new error that was discovered was a new feature lol. At the very least, I guess you could say it was an experimental model.
A little more detail on what Mr. Turner does:
http://uketalk.com/reviews/compass-rose.html
There was some discussion here a little while back but have not located the post.
My guess is that at just a post card thickness, there may be some buzz.

erich@muttcrew.net
07-27-2010, 10:35 AM
SWB, I think the floating fretboard sounds interesting - I must have missed that thread.

Chuck, the problem is not that I can't remove the neck right now. Actually I had it off in order to finish the neck joint and had to put it back on to take this pic. The problem is that I can't take it off again once the back is on as there is no soundhole that's big enough to do that.

14722

I'm not worried about the thickness of the soundboard - it's more likely to be too thick than too thin and is still awaiting some final tapering. There is a well sized neck block inside providing support from underneath. What's more, the fretboard only extends one fret beyond the joint, and honestly how much pressure do you ever put on the board up there? So I'm pretty sure the fretboard would hold up.

Fred, the potential buzz was what concerned me - I think the gap is big enough for that not to happen, but I suppose it would be better to scrape another 0.5 mm off to avoid any risk. As I said, once the back is on there's not that much I can do - I guess sanding from underneath would still be an option.

Timbuck
07-27-2010, 10:53 AM
Put another sound hole in it on centre ..You've already got Six ..one more won't matter much.

Moore Bettah Ukuleles
07-27-2010, 11:00 AM
What I've done in the case of an f-hole uke in which I had to remove the neck is to install a pick up in it. The 1/2" hole required for the pickup jack was enough room to fish a allen wrench attached to an extension rod. But there are easier ways to do what you want to accomplish.........
I wouldn't be worried about any pressure exerted on the fret board extension but rather the possibility of that are of the finger board to move, to either come up or down in time due to environmental changes.

Vic D
07-27-2010, 11:01 AM
Beautiful uke. I was just thinking while ago of a similar soundhole pattern for a tenor CBU I'm working on. Only I was thinking of a diagonal pattern running across the top. Now I'm thinking about the dots too...

Gaps bad man... I'd have to fill it with a sheet of black fiber or veneer or something if I couldn't get the neck off.

The neck may incur an ever so slight bow down the road... if it doesn't buzz now will it buzz then?

erich@muttcrew.net
07-27-2010, 11:46 AM
...The neck may incur an ever so slight bow down the road... if it doesn't buzz now will it buzz then?

Man, I hear you Vic. The strings aren't even on it yet, and believe me we are not timid about string tension. I guess a shim is the way to go.

erich@muttcrew.net
07-27-2010, 09:23 PM
Put another sound hole in it on centre ..You've already got Six ..one more won't matter much.

Ken, we were considering a trap door ;) or a bolt-on back :D

Actually, the total soundhole area adds up to almost exactly the area for a single soundhole (based on the helmholtz calculation for the box), but we haven't used multiple soundholes before so I have no idea whether this is going to sound any good. I think we're going to need to thin the soundboard quite a bit to get the volume up.

Timbuck
07-27-2010, 09:35 PM
Chuck's idea is the best ..drill a hole through the tail block..if you dont use a jack socket you can always fill it in with veneer...or a champagne cork.:D
Or you could use a Perch pole like a banjo.??

erich@muttcrew.net
07-27-2010, 10:11 PM
...At the very least, I guess you could say it was an experimental model.

Honestly, just about everything about this uke is experimental - at least for us. We have

a crazy asymmetrical soundhole pattern
diagonal bracing, because of the asymmetrical soundholes
holes in the headstock that match the crazy soundholes
a bolt on neck, which we've never tried before
...


I should not have posted this list, because now I'm thinking this uke really doesn't have much going for it - unless you happen to like the design. This isn't experimental, it's lunatic!

erich@muttcrew.net
07-27-2010, 10:20 PM
Chuck's idea is the best ..drill a hole through the tail block..if you dont use a jack socket you can always fill it in with veneer...or a champagne cork.:D
Or you could use a Perch pole like a banjo.??

Yes, I do like Chuck's idea. And with a pickup we should be able to crank the volume up a bit. Maybe plug 'er into our 200W Marshall - that should do the trick.

thistle3585
07-28-2010, 05:04 AM
[QUOTE=erich@muttcrew.net;426246]
Chuck, the problem is not that I can't remove the neck right now. Actually I had it off in order to finish the neck joint and had to put it back on to take this pic. The problem is that I can't take it off again once the back is on as there is no soundhole that's big enough to do that.

Is there some way to utilize an endpin plug similar to a violin or mandolin that will allow access to the neck bolt using and extension.

erich@muttcrew.net
07-28-2010, 07:04 AM
Is there some way to utilize an endpin plug similar to a violin or mandolin that will allow access to the neck bolt using and extension.

Andrew, we were sitting around the table just an hour ago pondering whether a pickup jack would actually work - the ones we have are all closed. Anyway we came up with the idea of just using a violin endpin.