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ChuckBarnett
11-14-2017, 08:31 AM
First build, tenor uke. Planning to do a bolt-on neck with no mortise/tenon and no reinforcement rod(?)

I have the sides joined and not sure what to do next. Should I install the top and then figure out how to do the neck joint? Or... ?

A step-by-step guide for the boy-child would be nice. :)

Again, I'm very grateful for all who've helped me through this first instrument build. I promise that I will ask fewer questions once this is done!

Chuck

Wildestcat
11-14-2017, 10:30 AM
You can find some details on the method I use from my contributions on pages 15 to 17 of the 2x4 thread. http://forum.ukuleleunderground.com/showthread.php?114726-2x4-challenge/page15
You will need to make some form of drilling jig to ensure everything lines up correctly, and on centres. Essentially involves drilling a 10 mm hole down into the neck heel to accept a 20 mm long barrel nut. Then a 6 mm hole in the end of the neck to meet the barrel nut hole. Use the same jig to drill the 6 mm hole through the headblock of the completed body. I usually enlarge the hole in the neck end to 1/4" to give some wiggle room.

It is best to do all the drilling work on the neck before you do any carving work on it. A rectangular section makes aligning and clamping the jig so much easier. I use the piece I bandsawed out to create the heel curve, taped back in place as a packer for the horizontal clamps.

jcalkin
11-14-2017, 10:44 AM
I recommend that you finish the body first. Do your best to maintain a 90 degree angle between the top and the neck area of the ribs. Then you have at least three choices. You could glue a threaded rod into the face of the heel and put a nut on it from the inside of the box (the banjo method). Or you could use a threaded insert that screws into the front of the heel and accepts a bolt from inside the box. Or you could drop a threaded steel dowel into the neck (usually from the top) that accepts the bolt from inside the box.

The first method is the easiest, but if you have to make adjustments to the heel to get it to follow the centerline of the body you'll likely have to pull the threaded rod out after heating it.

The second method is fairly easy too, but if you carve a delicate heel it may crack from the stress of having screwed the insert into the end grain.

Number three is the most sophisticated but also the most difficult to pull off accurately.

You could also sink a long screw through the heel and into the neck block, using a strap button as sort of a washer. It works fine, and you won't have to fiddle about with nuts or bolts inside the body.

Sven
11-15-2017, 02:39 AM
Weighing in after Chuck Moore isn't something I'm really comfortable with since I'm a hobby builder and a big fan of his, but what the heck.

I attach my necks before glueing on the back because 1) I think it's easy, and 2) I like to cover the heel with the back rather than doing a separate heel cap. So I'll put a link to one of my blog posts that show my jig and my method.

The jig in the pics have two holes. I use both when drilling in the neck but so far I've remembered to use only one when drilling the body and into the heel block.

http://argapa.blogspot.se/2014/09/setting-neck.html

I'd recommend taking Chuck up on that offer. If I were close he'd have had to kick me out of his shop many times by now!

Moore Bettah Ukuleles
11-15-2017, 07:21 AM
Like Sven, I'll temporarily attach the neck after the top is glued to the sides but before the back is glued on. After the neck is properly adjusted I will then clamp the assembly (through the sound hole primarily) onto a solera of sorts which keeps the neck aligned to the body while I glue on the back. Once the body is closed in then I'll unbolt the neck and bind and finish the two elements separately. Before I glue the fret board onto the neck I will again temporarily attach the neck to the body to make sure it is still aligned properly and I very occasionally have to make minor adjustments. That's the beauty in bolt on necks as I see it; the ability to build and finish the neck and body separately and the ease in making adjustments along the way.

ChuckBarnett
11-15-2017, 12:28 PM
THAT IS QUITE AN OFFER!!

We've been to Oahu, Maui and Kauai, but never the big island. I mentioned that to Mary Lou this morning and we just may have to do that! Grateful for builders who take the time to help others. There is one near us -Brian Griffin in Bellingham, who has been very encouraging thus far! I also know a guitar builder in Edmonds, WA, Bob Carnahan ,who makes a run to Hawaii now and again.

Chuck B

ChuckBarnett
11-15-2017, 12:42 PM
Thank you, Sven. I looked at your blog -well done! Okay, a "barrel nut" is different than a 'threaded insert' used by some folks. Thus the larger hole in the neck at 90 degrees to the one drilled for the bolt. Only one bolt? The neck won't twist? And how to accurately align the block with the neck heel to drill is a bit of a challenge for me. I can understand gluing the top on (I'd assume the neck has to be pretty-well flat by this point) and then using a jig like yours to drill the block. Some people use "hanger bolts" that screw into the neck and offer a threaded stud through the heel block.

ChuckBarnett
11-15-2017, 12:45 PM
I didn't think of extending the back as a heel cap. My plan from LMI calls for a different level for the back and the heel cap. I'll just make something.

ChuckBarnett
11-15-2017, 12:50 PM
Excellent overview of options. I am getting a better grasp of all this as I read. Thank you!

Looks like Chuck Moore and Sven do a barrel nut in the neck, drilling down through the neck for that. I like that idea at this point. Just trying to grasp how to line things up to do that and why it works without the neck swiveling at that point.

Pete Howlett
11-15-2017, 01:00 PM
Make a simple jig - some things just don't require sophistication. Bolt-on necks make alignment and neck angle a simple solution. Finishing is simpler than with an integrated neck as is executing binding. Cannot understand the slipper heel method or dovetail. Some things make sense to me, othersleaveme scratching my head... why make it difficult for yourself? I've had a masterclass in slipper heel making too and it simply reaffirmed my views on it. All praise to those who can do this work.

Sven
11-15-2017, 09:43 PM
... Only one bolt? The neck won't twist? ...

Nah. The fretboard and, in my case, the overhanging back will secure it. I also put a bead of glue around the edges of the heel when I screw it on. One thing that may not be obvious in the post that I linked to is that I relieve the centre of the face of the heel a bit so only the edges have to be sanded to fit the body. Holding a neck straight up on a sanding plate and dragging it back and forth will otherwise make it convex, destroying all chances of a tight fit.

Timbuck
11-15-2017, 10:26 PM
Here is an interesting thing about neck joints by David C Hurd "KAWIKA UKE'S" a guy who fitted necks via a a butt joint with no screws or bolts ...just epoxy ;) http://www.ukuleles.com/BuildingHowTo/neck2body.html

Wildestcat
11-15-2017, 11:01 PM
I also put a bead of glue around the edges of the heel when I screw it on. One thing that may not be obvious in the post that I linked to is that I relieve the centre of the face of the heel a bit so only the edges have to be sanded to fit the body. Holding a neck straight up on a sanding plate and dragging it back and forth will otherwise make it convex, destroying all chances of a tight fit.

I do the same as Sven. The jig is essential for accuracy, but pretty simple to make. It helps with alignment if the jig width matches your neck blank dimension - in my case 60 mm. Also, if you are not intending to do lots of these then you probably don't need the steel inserts. Hardwood should be fine

I use essentially the same method on steel string standard & tenor guitars, but with a tenon and two bolts ... sorry about the sideways orientation - I can't seem to correct it! Also the pictures are not in sequence ...

104440 104441104442 104443104444

The 4th picture is the test piece for the jig, but shows the depth stop on the 10 mm drill.

The screw poking out of the top of the completed neck is to allow the barrel nut (for the guitar I am using a longer twin-hole item) to be pulled back out if necessary. I drill and tap a 4 mm screwhole in the top of the barrel nut before I insert it. I like a pretty tight fit, and if the nut fails to bottom fully then you need to be able to extract it. The screw allows you to both position the nut radially and to lever it out again if you need to. You could also drill a small hole up from below into the nut cavity to poke it out with a rod - the hole later being covered by the heel cap.
Once everything is checked and all the bolts line up, I run a little CA glue down into the hole to lock the barrel in place permanently.

Sven
11-16-2017, 02:05 AM
I must admit I never thought of drilling the nck blank before carving. Seems like there are obvious advantages.

Wildestcat
11-16-2017, 03:56 AM
As it happens, I had a neck to do this morning, so I took a few more photos - hopefully self explanatory. This is a one piece neck, so to give the horizontal clamp something to bite on I taped the heel offcut back in place.

Again - sorry for the orientation of the photos (the clamp referred to as "horizontal" above is of course the vertical one in the picture...

104448 104449 104450 104451

Sven - I do as much as I possibly can to the neck whilst it is still easy to clamp in a vice!

Wildestcat
11-16-2017, 05:02 AM
And for completeness, here is the body end of things:

104452 104453 104454

The green tape on top of the guide bush is to stop reflections whilst I look down the hole with a torch to verify alignment!

Timbuck
11-16-2017, 10:07 AM
I don't do bolt ons ...and by the looks of all those jigs and careful drilling operations I'm glad I don't do em ;) but if I did I would use smaller HT bolts and cross nuts..cos M6 or 1/4 inch is way over the top for wood..M5 or M4 is plenty strong enough...as I've said before my bike saddle is locked in place with one M5 set screw.:)

Wildestcat
11-16-2017, 01:33 PM
It's more a case of what's readily available Ken - 10 mm dia. cross dowels with 6 mm screws are the standard furniture fixings, available from Screwfix for about 3 for 50. Rest assured they work just fine, even if over engineered for the task!

sequoia
11-16-2017, 06:29 PM
I struggle with neck to body connections. What drives me crazy is that all the directions and illustrations are for a flat, flush, square joins and I use a radiused joint. This adds a whole different level of complexity. Nobody ever talks about getting a radiused join just right with bolts. Flat, flush, square neck to body joins look lame to me and are easy to do. I'm sorry. Show me how to square a radiused butt joint with bolts and I will be happy.

(Apologies. I just spent a frustrating afternoon in the shop with a very balky neck to body join. Kinda pisses a guy off.)

DPO
11-16-2017, 07:23 PM
I struggle with neck to body connections. What drives me crazy is that all the directions and illustrations are for a flat, flush, square joins and I use a radiused joint. This adds a whole different level of complexity. Nobody ever talks about getting a radiused join just right with bolts. Flat, flush, square neck to body joins look lame to me and are easy to do. I'm sorry. Show me how to square a radiused butt joint with bolts and I will be happy.

(Apologies. I just spent a frustrating afternoon in the shop with a very balky neck to body join. Kinda pisses a guy off.)

Try joining a banjo uke neck to the body. The body is 8 inch diameter and the neck has a break angle of 2.5/3 . That's a fun join!

Wildestcat
11-16-2017, 11:14 PM
I struggle with neck to body connections. What drives me crazy is that all the directions and illustrations are for a flat, flush, square joins and I use a radiused joint. This adds a whole different level of complexity. Nobody ever talks about getting a radiused join just right with bolts. Flat, flush, square neck to body joins look lame to me and are easy to do. I'm sorry. Show me how to square a radiused butt joint with bolts and I will be happy.

(Apologies. I just spent a frustrating afternoon in the shop with a very balky neck to body join. Kinda pisses a guy off.)

But why make life hard for yourself just for the sake of it? There are more than enough other potential pitfalls and frustrations on the road to producing a nice instrument to keep me happy! This is one you can very easily design out, and I actually prefer the squared off shoulders look of a body with a flat neck joint face :) Just to add insult to injury, I used to do radiused tailblocks but these days they are flat as well. ;)

mikeyb2
11-17-2017, 03:55 AM
Try joining a banjo uke neck to the body. The body is 8 inch diameter and the neck has a break angle of 2.5/3 . That's a fun join!

and to complicate things further, try joining a 5 string banjo neck to the rim. Not only do you have to consider the neck angle and the rim diameter, but also the "skew" angle of the neck to the body. The neck has to be square to the rim and frets, and drawing a line down the centre of the peghead down to the heel would be wrong. The actual centre line is the 3rd string, so this also has to be included in the mix. I made a jig which does all these in one operation, using my drill press and sanding drum.

sequoia
11-17-2017, 06:29 PM
Just to add insult to injury, I used to do radiused tailblocks but these days they are flat as well. ;)

(Runs from room sobbing and bursts into tears.) Forsooth Wildestcat. Shame. A square tailblock. Anybody can make a radiused tail and block. It ain't hard. Now a radiused neck and block. That is hard.

Wildestcat
11-18-2017, 12:42 PM
(Runs from room sobbing and bursts into tears.)

I won't sleep with this on my conscience, so I'll level with you .... I still do a radiused tail on tenors. But ..... if I ever need to make a new mold ......... need I say more ;)

Ken Franklin
11-18-2017, 10:46 PM
(Runs from room sobbing and bursts into tears.) Forsooth Wildestcat. Shame. A square tailblock. Anybody can make a radiused tail and block. It ain't hard. Now a radiused neck and block. That is hard.

Fit it square and then radius it. Or do as I do and route a relieved section and only radius the outside edges.

ChuckBarnett
12-02-2017, 05:20 AM
Paul, thank you very much for the detail and the time you've taken to shoot some photos! I would suggest regarding the orientation of the photos that a simple fix would be to turn the camera or phone 90 degrees clockwise or counterclockwise and see what happens. With my Samsung phone I shoot pictures in landscape mode rather than vertically in portrait mode and so I don't have to rotate them.
But the real question I have is regarding measurements. I can guess that you are installing the quarter inch bolt roughly 40% of the way down from the top on the heel and the barrel nut and should be no closer than what, 8 mm from the end of the neck? To make this jig, I will need to determine what I want those distances to be.
And I finally figured out from a comment in this post above that the round thing with the sized hole is a guide? I assume you can buy those rather than make them?
Once again, you're talking to a greenie in terms of woodworking. Learning but have a long way to go.

ChuckBarnett
12-02-2017, 05:48 AM
Also, when I measure this barrel nut it turns out to be 25/64 of an inch in diameter. I will need to buy a drill bit and this could be a brad point (as I see in the photo for the horizontal hole, the quarter inch hole) or a Forstner. Or am I actually hunting a 10 mm drill bit? I welcome advice.

Titchtheclown
12-02-2017, 05:15 PM
Flat pack furniture was invented by the Swedes so ISO/metric measurement is the go.

Timbuck
12-02-2017, 11:31 PM
yes ... 10mm hole required. :) with a 6mm cross drill....However I think this is a bit on the large size ..I would go for the size smaller requiring an 8mm hole with a 5mm cross drill..to fit this nut https://www.ebay.co.uk/itm/M5-x-8-x-16mm-Steel-Cross-Dowel-or-Barrel-Nut-Centred-Hole-20-Pcs-100627/271321373423?hash=item3f2c039aef:g:JQMAAOxycD9TS~n 3

ChuckBarnett
12-03-2017, 06:50 AM
Thanks, Ken!
You all are amazing folks! ...doing my shopping for me and such!

Titchtheclown
12-03-2017, 06:58 AM
If you are near an Ikea they have every connection under the sun for a donation to UNICEF. Notionally spare parts for when the packing department forgets to put something in the box.

Wildestcat
12-03-2017, 08:51 AM
I can guess that you are installing the quarter inch bolt roughly 40% of the way down from the top on the heel and the barrel nut and should be no closer than what, 8 mm from the end of the neck?
And I finally figured out from a comment in this post above that the round thing with the sized hole is a guide? I assume you can buy those rather than make them?

Hi Chuck. The dimensions I work to for sopranos, concerts and tenors are as follows:

End of neck to centre of 10 mm barrel nut hole = 14 mm
Top of neck to centre of 6 mm bolt hole = 22 mm

On baritones, I increase the distance from top of neck to centre of 6 mm hole by 3 mm to 25 mm.

In the UK, the steel drill guide bushes are available as a set from Axminster Power Tools, but if you have access to a lathe you can make your own. If you are only aiming to make a small number of instruments, then just an accurately drilled hole in a reasonably thick hardwood or birch ply jig should be good enough.

I use Veritas brad point drills for the holes, as you won't get engagement between the bush and the reduced shank diameter of a Forstner.

Feel free to follow Kens suggestion for smaller components, but 10 mm / 6 mm is by far the most readily available size and works just fine on all sizes of uke.

ChuckBarnett
12-04-2017, 04:54 AM
Great idea. We are some distance away but on occasion get down through Renton Washington on our way somewhere.

ChuckBarnett
12-04-2017, 05:06 AM
Thank you, Paul! This is very helpful, a very good place to start. I have just discovered that not all drill guides and depth stops are created equal. Local hardware store had a kit of drill guides and a kit of depth stops both of which are anything but accurate. Can't get a 3/8 in drill through the drill guide, nor can I force the 3/16 inch centering point through the 3/16 in drill guide. I found three of the same depth stop and the kit is missing some of the sizes listed. Sort of captures the story of my luthier experience thus far... All the time and learning it takes to get up to the surface to simply do the job. Not giving up. :)

DPO
12-04-2017, 09:15 AM
Thank you, Paul! This is very helpful, a very good place to start. I have just discovered that not all drill guides and depth stops are created equal. Local hardware store had a kit of drill guides and a kit of depth stops both of which are anything but accurate. Can't get a 3/8 in drill through the drill guide, nor can I force the 3/16 inch centering point through the 3/16 in drill guide. I found three of the same depth stop and the kit is missing some of the sizes listed. Sort of captures the story of my luthier experience thus far... All the time and learning it takes to get up to the surface to simply do the job. Not giving up. :)

Banjo Ukes and indeed some banjos use a simple lag bolt as a neck joint, I have built around fifty banjo ukes and twenty ukes usin the lag bolt or hanger bolt method with zero issues. Just a lot easier than the furniture connectors most people use.

ChuckBarnett
12-07-2017, 03:12 PM
Thank you, Dennis. Like was said earlier, there are many ways to do this sort of thing. I will do the barrel nut method for this first one. And who knows what I'll do next. :-)