Official Luthiers Forum!

Darrel,

I believe that my issue is probably the tolerance with the dowel itself. I tried to slightly enlarge the hole to make it not so tight. This crack is just the end of a long fiasco series of events. This whole thing is just one bonehead move after another.

I did not drill the hole all the way through. This is my second attempt at seating a down in the heel. On my first attempt I cut a notch in the down to let the air escape. I got about ½ way through and the dowel stuck. I was thinking it was possibly due to the glue. I ended up boring out the dowel and cleaning up the hole. Once I was done, I had a slight bit of clearance on the bits I was using. I drilled a hole in some Oak scrap and was able to get the dowel through that hole as a test.

The dowel was still tight. For my last attempt I used the drill press to press it in the hole dry. My plan was to wick some CA in once it was seated. I know, in hindsight that just doesn’t sound like the best plan, but that is what got me here. I think that I either didn’t widen the middle section of the hole as much as I did the ends, or the dowel was a hair fatter in the middle. Air escaping could have been a part of it too.

I like your idea of sizing through a metal plate. I will have to pay more attention to the fit next time. I'm probalby going to try the CA crack fix on this one.

Thanks,

John

Re a series of bone-headed moves, I know exactly how you feel. Been there, done those, still doing some. The reality is that, when you're teaching yourself to build guitars, you run into situations you didn't know enough to anticipate, find you lack skills you didn't know about, and there are times materials and tools don't behave as you expected. All you can do is try to fix the mistakes, remember the lessons learned, and move forward. Sometimes you have to invest money as well as time, such as when you buy a new neck blank and start over.

Re this particular instance: if you can't get the crack closed with a clamp, flooding with CA is more cosmetic than structural. Sounds like your dowel is pushing the wood, holding the crack open. Rather than CA, I would suggest working in slow-setting epoxy, then clamping with moderate pressure. Thick lines of CA are weak; thick lines of epoxy are relatively strong. After epoxying, watch to make sure the epoxy doesn't seep out before it sets, and also clean up any excess before it sets.

If you can't get a sound joint this way--which is a judgment call depending on how it looks clamped--rather than go forward with a compromised neck joint I would suggest drilling out the dowel once again and gluing in a correctly-sized dowel with epoxy.

_________________
Tim Allen
"Never hurry, never rest."

I would have thought that a 1/2 " dowel might be fine to accept a 1/4" hanger bolt, but is a tad on the skimpy side to accept a 1/4" threaded insert. Perhaps a 5/8" dowel would have been a better choice ?

Murray,

That probably is a good point. Although I'm not sure how significant it is (meaning is it worth a redo). I have read where a number of people don't use the dowel at all. A ½” dowel may be a bit skimpy, but I bet it is better than nothing. Now a poorly installed dowel, I see as a problem.

I do have the hardware for both inserts and hanger bolts so I could use the hanger bolts. Honestly I really don't know. Moving to this type of joint on the fly has not been part of the plan at all.

As far as hanger bolts vs inserts I can see where fitting and adjusting the neck with the inserts might overall be easier than with the hanger bolts. But I suppose it would pretty much be the same as doing it with a tenon in place. I tend to over think these things.


Tim,

I see what you are saying and it makes sense. Unfortunately I had clamped it and filled it with CA right before you posted. I'm not sure if I could have worked the epoxy in there deep enough. Plus the wicking of the CA might help with the dowel.



In the back of my mind this is still a viable option except for the fact that I have now entered CA into the existing crack.

Did I use the word FIASCO before?

If it helps....

I used to use inserts, but now use hanger bolts. With a 1/2" dowel, the inserts would cut nearly all the dowel, so there wasn't much point to it, and since I carve a rather dainty heel, I want a dowel in there. One day I realized that Collings uses 1/4" hanger bolts, and that was all I needed to know. Good enough for Bill Collings, good enough for this redneck. That was many yeas ago, and I've had zero issues.

As for the butt joint, well, I've used it since 1996, other than roughly a year's worth of guitars in '98/'99 that I built with dovetails(wanted to know, for sure, if dovetails sounded different or better... They don't.), again, with zero issues. Taylor's built several hundreds of thousands of guitars with a butt joint, too, with no problems. Even their "new" joint is essentially a butt joint, albeit recessed a hair.

Bottom line is, a butt joint makes an excellent neck joint; it does not require a large neck block, is simple, and lightweight, yet is perfectly solid and sound. Heck, you can even get away with a shorter neck blank, if that matters. So, don't apologize to anyone, not even yourself, for using a butt joint. Once you've done it, you'll chuckle every time you read of someone's new jig, or trials and tribulations with M&T joints....

Keep It Simple! Life's complicated enough on its own.

Edit to add: when you drill for the dowel, drill through until at least the point of the bit comes-through the other end. I use a spade bit, specifically designated for this task, so that every time I drill for a dowel, I know what size the hole will be. Yes, bits do vary... Also, test-fit the dowel, dry. Always, always, do a dry fit. If you can't push the dowel in at least halfway with thumb pressure, it's too tight. Most dowels aren't round, so use a plane, or a sanding block, to knock-off the higher edges. An again, not all 1/2" dowels are 1/2". When I buy dowels, I take a micrometer with me. Honest! There's a lot of variation in that dowel rack.... Do NOT assume the dowel will fit. Test, and don't apply glue until you are SURE that the fit is just right. For glue, just a bare minimum of Titebond is needed. It should be almost dry, there should be so little glue. Push the dowel in, and quickly grab a hammer and tap it home, as the glue will "grab". I've never been able to push a well-fitted dowel in all the way with my bare hands, yet I've never split a heel while using the hammer, either. It's all about getting the fit just right, and of course, having an escape for the air and glue(IE: the through-hole).

Taylor Guitars is a home shop?

Just wanted to add, when dry-fitting the dowel, push it in as far as it will go easily, then rotate it a bit, and pull it out. Take a look at it, and the shiny spots are the high spots that you need to knock down. It's as simple as that. Knock down those shiny spots until it fits just beautifully.

BTW, a few years ago I dropped my first guitar while carrying it in a gig bag, and the heel cracked. The action rose a bit, so I immediately took the string tension off of it, until I could get back home to fix it. The crack was very tight, so I just set up some clamps, warmed the heel a bit with a hair drier, and packed some hot hide glue into the crack and clamped 'er shut. It barely shows, and is still solid today! A 5 minute repair. Without a dowel in there, I doubt it would have been nearly as painless. Moral of the story? I don't care what type of neck joint y'all use, you should consider reinforcing the heel with a simple dowel. Costs next to nothing, takes but a few extra minutes, and can make a real difference when/if something bad happens to the guitar later.

The wood dowels in the hardware stores around here are slipping in quality. They are all over in terms of dimensions, and the wood is some mystery white wood from China that is quite soft. I'm thinking of ordering some higher priced, hard maple dowels but I wonder if that is overkill.

I use the maple ones from LeeValley.

I've noticed the mystery wood dowels, too, so when I spot some decent maple ones(they're out there), I grab all that they have. Hoarding has its benefits...

Avoid the big box stores, and shop the smaller Mom 'n Pop hardware store.

Can't go wrong with anything from Lee Valley, either, for that matter.

I get 48" long maple dowels from a local Mom and Pop lumber store. (actually I got several a couple years ago.....a lifetime supply) I take my mic, and pick ones that are bigger than 1/2". I drill a 1/2" hole (with a dedicated forester bit). I cut the dowel ~1" too long, chuck one end in my drill press then "turn" it with 80 grit until it fits. Obviously a lathe would be the correct tool, but I don't have one. I dowel my blanks, as soon as they're profiled.

_________________
I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Thanks for all the feedback. I really appreciate it. Grumpy, I had looked over your site when I was starting to shift to this type of joint so thanks for the support here.

I’m going to go ahead and use hanger bolts. I like the idea of removing less material from the neck to secure the hardware.

I went ahead and drilled out the dowel that caused the crack. My main reason was because since it was currently stuck with the “Dry” fit, I didn’t want to risk the possibility that CA wicked in wouldn’t hold it in place. As it turns out this was a good idea. The dowel had only seated to where the crack stopped in the neck. So I had a large gap from the top of the dowel to the bottom of the hole.


If I had tried to install an insert here, the gap would have been exposed. I drilled out the center of the dowel with smaller bit and was able to tap the dowel out through my new vent hole in the bottom of the truss rod slot.

I just wish I hadn't filled the crack with CA. I guess that is another lesson learned.

I bought my dowel at Lowes. They had a bunch of really soft hardwood. I noticed that some of the ones in the bin varied in color so I did the thumbnail test and found a maple one. The dowel I have measures between .512 and .517”. I hadn’t really considered that the dowel would be so oversized.

I’ll work on thinning the new dowel down (probably using Woody’s Drill press technique) and getting a better fit before I move on.

John

I am slightly bemused as to why experienced builders like Mario and Woody would mess around trying to get dowels to fit, when they could just buy a Lie-Nielsen dowel plate.

A couple of whacks with the mallet, job done ...

A home made mild steel dowel plate, like what I have made on occasion (for other applications) , does the job, sort of, but I like that the Lie-Nielsen plate is made out of hardened tool steel.

would mess around trying to get dowels to fit, when they could just buy a Lie-Nielsen dowel plate.

Well, I hate buying tools unless they improve my work, or pay for themselves with time savings. That plate would do neither, since it takes me seconds to fit a dowel with the small plane that is always at my side, if not in my pocket. In the time it would take to take out the plate and fix it in a vise, then drive a dowel through it, I'd have already fitted the dowel and glue it into the heel.

Instead of looking for new tools to buy to overcome a new obstacle, it's better to look at the tools you already have and figure out if they can also do the job.

Keep. It. Simple.

Dowel plates might cut a constant diameter, but they certainly couldn't straighten a dowel.
Think of hammering a curved dowel through a hole, the diameter would be correct, but the dowel still wouldn't fit the hole!

_________________
http://www.bobmatthewsguitars.co.uk

Would the dowel even need to be glued?

_________________
Chris

Well I think I have the neck joint issue under control. Thanks for the tips. I ended up fitting the dowel and using epoxy as glue. I got the hanger bolts installed. Now I just need to drill the holes in the body to accept it. I see a jig involved there.

I plan to use these bolt caps instead of the basic hardware nuts and washers.



I think they will have a decent look from inside the guitar. It will be pretty much how it would have looked if I had done the mortise tenon joint with the barrel nuts. Are there any issues with these holding?

I counter sink the holes, and cover the nuts up with a label..........but I like those "bolt caps". Where do you get them?

_________________
I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

I picked these up at Ace Hardware. But I have seen them at Home Depot and Lowes too. They are in with the furniture hardware.

Bolt Caps is what they are called on the Lee Valley site.

I've used those caps on my last 3 or 4. They work well. I got them at Home Depot.

The problem I see with the bolt caps is that the hole in the heel block has to be bigger. Probably more slop unless you step drill it.

_________________
Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

The bolt caps I have fit into a 23/64” hole. For alignment issues\adjustments I was thinking I should bump this up slightly, but am not sure how much. Right now I’m thinking 3/8”. I don’t want to oversize it needlessly, but on the other hand I don’t want to make the tolerance so tight I cause issues down the road.

For what it's worth, I step drill the hole for the cap nuts to 3/8" for these. It works for me.

That's why I like Woody's solution of countersinking it better. Less depth, easier to align.

_________________
Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

Why countersink or counterbore at all?

What could be sexier than two stainless steel domenuts standing proud of the neck-block? With a suitably sized washer, of course ...

Is the butt joint relieved in the center like a M&T, so that you only have to fit the edges?

When using hanger bolts, does the joint have to be perfectly fitted first? (seems like it would be difficult to measure the neck angle etc. without having the neck fastened) Do they come out easily?

_________________
Pat