Paul M
Forum Replies Created
-
I bought this stuff, I haven’t used it a ton yet but it seems pretty good. I tasted a bit and it definitely burned.
Everclear 190 is not available in many states, most of the Northeast doesn’t have it (I think just CT).
They occasionally offer free shipping.
If you buy the 1L bottles, there is no hazmat fee. So I bought 4x1L.
https://www.laballey.com/products/food-grade-ethanol-200-proof?variant=41773203619995
laballey.com
Lab Alley offers lab grade and small business 200 proof food grade ethanol. Our ethyl alcohol is food safe with no additives. A pint is $30 to pallets for $9,504. Buy at laballey.com.
-
Seems like West System mostly recommends the G/Flex for Aluminum at this point, they used to offer an etching kit for the 105 system but don’t use it anymore.
I like the thickened stuff in the toothpaste tubes a lot.
https://www.epoxyworks.com/index.php/aluminum-adhesion/
epoxyworks.com
Tom Pawlak tests aluminum adhesion and compares the results of WEST SYSTEM G/flex 650 Epoxy against WEST SYSTEM 105 Resin/206. Slow Hardener.
-
What are you using it for? Can you press a back with it?
-
there’s the Nuclear option:
https://www.stewmac.com/luthier-tools-and-supplies/types-of-tools/calipers/mag-ic-probe-ble-thickness-gaugeAlso the Hacklinger gauge, but I think the digital one would be preferable.
There’s an article in the most recent Guild magazine about making a DIY version that seems to make sense:
https://luth.org/journal/american-lutherie-149-summer-2023/I think there’s a Dan Erlewine/Stewmac video about one of his students measuring a Gibson guitar for copying from a couple of years ago.
I found it:
https://www.youtube.com/watch?v=QBQ9JZgFPgostewmac.com
MAG-ic Probe Thickness Gauge - StewMac
MAG-ic Probe is an electronic thickness gauge for accurately measuring the thickness of instrument tops, sides and backs.
-
perhaps a bit of filing, long strokes the full length of the slot, blending that into the remaining slot. The thing is it seems like it’s only in your inner layer so it’s probably not going to be all that visible to anyone. It’s also a “non-player side” error, the person playing the guitar is not going to see it.
Definitely an easy one to make the repair look worse than the error.
-
forget what I said.
-
-
I am very low on the experience scale here but I did use fish glue on a few guitars that ended up having frets move later on. Partly due to the slots being a little sloppy but I read that Fish glue is (maybe particularly) sensitive to heat. I am going to go back to CA glue.
-
Could be “structured sides” as pioneered by (I think) Michael Kennedy and Jeremy Clark in Montreal.
Pictures in this post show my first attempt that them. I call them ‘cored’ sides.
In my case, 2 1.5mm veneers and a 6mm softwood full width kerfed core.
instagram.com
17 likes, 0 comments - paulmcevoyguitars on June 17, 2023: "Some construction pictures from my first Selmer Style Gypsy Jazz Guitars. #luthier #guitarmaker #..."
-
I haven’t used them for cleaning fret slots, but I do use these bits in my cnc for routing fretboards. I was sure I was going to break one, they are so spindly and thin, but I have yet too.
<div>Anyway, they might work for cleaning out slots and they are cheap AF. I might go with the 0.4″</div><div>
</div>
https://www.amazon.com/gp/product/B073RJ3SYZ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1 -
I get that, totally. That’s sort of what led me to do it at first.
The one thing I would say is that if you’re interested in repair work or just being a well rounded luthier, understanding dovetails and tenon/bolt on necks is fairly essential stuff.
And the other thing is that you’re in uncharted territory with these adjustable necks. They are very uncommon and if you get into a spot where you need advice there really isn’t any. If you screw something up on a bog standard Dreadnought, you can ask a million people, and also there’s tons of educational stuff available.
But for me I’m glad I did it when I did it. I think it makes a superior guitar and has tons of advantages. It definitely changes the guitar you make, particularly if you’re doing cutaways, but so far the few trade offs have not been an issue for me.
-
To answer your question about the 2nd bolt though I was using a nylon one, no rattling but still annoying. And yes, the strings hold everything together. It’s not particularly difficult to string up from scratch but definitely preferable to leave 3 on and change the other 3. One string at tension is enough to hold it together for a restring.
I should note that this may or may not be descendant from a “Stauffer” style neck joint. Gary Southwell has a more traditional Stauffer style neck joint, and the guys at Miles End Guitars in Montreal, who are all kind of amazing, use a modified Stauffer style, as does Sergei Dejonge when he does adjustable necks.
If you’re not familiar with those guys, they are on instagram, 52 Guitar Company, Mike Kennedy and Larkspur guitars, there’s a few more of them and they are all very very good and very innovative and they collaborate on ideas.
-
There’s nothing in my heel at all. There’s a gap in the block so the heel can move in and out, that’s all buried in the heel pocket.
This isn’t described in the Gore book but in some forums I’ve seen him posting in after the books came out. I’m not sure if he’s still using it.
I was using two bolts originally, one that was just loose in a slot to hold the neck on if there were no strings on it, but it was annoying to have to reach in to put it in, and in the case of the Django guitars, impossible to get to because of the small sound hole. It really doesn’t serve much of a purpose. So now it’s just the single set screw.
I was using threaded inserts initially to hold the set screw but saw a youtube video testing threaded inserts as not being any stronger than threaded wood. So I’ve been tapping the wood instead. I chase it with some CA glue and retap it. So far so good.
For the record, if it’s your first guitar build, depending on your woodworking and design experience, you might want to try a bog standard mortise and tenon…I’m glad I built a few dovetail guitars at first. Although in many ways the joint I’m using is simpler to fit than a traditional joint, I have pooched the neck angle measurement on the last two fairly significantly and was able to adjust the height of the slot in the neck and compensate for it. I did it all on CNC…I might or might not find it challenging without that (I mean, I made all my jigs on CNC and then used a router to route them, and made the neck on the CNC, but I would have trouble making all the jigs work without the CNC, I think).
-
shit sorry. One more link:
https://uptonbass.com/shop/upton-bass-adjustable-removable-neck-upgrade/I imagine this is somewhat like what the Keith joint is talking about? This is very very common with modern upright basses. I don’t know what the mechanism actually looks like. I think they sell it to luthiers for retrofitting to other instruments. Some sort of track system with a screw of some sort.
uptonbass.com
Upton Bass Adjustable / Removable Neck Upgrade
Double Bass Removable Neck Upgrade Travel Bass
-
If you find a mechanism for the sliding joint, I’d definitely like to see it.
One thing you could do, without a mechanism, is have the neck sliding on some sort of channel but just have a set screw retaining it. So loosen the screw and slide it where you want it and then tighten it. Logical place would be to put the set screw in the heel, I just don’t love that aesthetically (perhaps some people don’t like my set screw in the fingerboard but I think it’s less noticeable with the visual noise from the strings).
I’m interested though, I don’t love that lip on my guitars.
The other thing I like about the design I’m using is that it puts the stress against the long grain of the neck (I have a fairly significant tab below the fingerboard that’s sunk into the body, and a big neck block below that). I don’t really love that on the designs where the adjustment is in the heel it’s stressing the short grain of the heel. I’ve not heard of them breaking at the heel but it doesn’t seem ideal to me. In the Gore design, the heel is basically non-structural passed the slot where the tab goes in.
-
are there ANY Japanese lawsuit era guitars that consistently have dovetailed joints?
-
oh and the other sort of annoying thing is that it might get in the way of your truss rod if you’re running your truss rod near the end of the neck (I still haven’t figured out how far I want the rod to go).
I think on the next necks, if I decide to run the rod all the way, I will offset the set screw to the treble side where I’d potentially want more stability anyway. I don’t think it will make any difference. Very worse case scenario I could use to screws.
I’m also using 1/4″ carbon fiber square tubes from Dragon Plate on either side of the rod (or no rod at all for the classicals).
-
This is what I’ve been using, I think it’s the “Trevor Gore” neck joint. I’ve done 4 guitars with it, and I’m slowly refining it. I think you can see how it works from the pictures. Basically the neck pivots on a tab, there is a slot in the neck heel to ride on the slot. With the strings on you can lift the guitar by the neck. It mostly stays in tune even with adjusting the neck.
On the classical guitars I did, it was really hard to get a tight fit to the heel with the sort of traditional wineglass heel. Going forward I’ll be doing a square Somogyi kinda thing…same with the Gypsy guitars. Or maybe a V shape that transitions into a wineglass, but whatever way the sides of the pocket will be straight.
The one thing I don’t like about this is that in a cutaway guitar you have to have a lip on the cutaway side (the cutaway can’t terminate flush with the neck). I have not had anyone comment on that as being an issue but I don’t love it. You could have a flush side with a sliding tenon thing, but the adjustment would be worse. I’m not averse to trying that at some point, but right now this is working.
Crazy crazy easy to adjust even on the fly.
Geometry is sort of tricky to work out, and I’ve had to fudge a lot.
The guitars I’ve made with this sound very good, I don’t think there’s any significance to the neck joint at all, as long as it’s more or less rigid.
Also it’s very nice to me able to finish the guitar and neck separately. Huge really.
Kind of a random bunch of pictures but I think you’ll get the idea. There’s a video in there too of the adjustment
https://photos.app.goo.gl/xjNawya1rFZ6itC29
-
Well for all my blathering, Ian fixed the problem.
It’s sort of hard to explain why constraining your sketches is so important until you start making more elaborate designs and having non-constrained sketches totally hoses you. I’ll try to make a little video about it if I can figure out a way of explaining it.
I think the basic thing is that if you are really, really good, and you’re nailing your design on the first try and you never want to modify it, constraining sketches becomes less important. And in this situation where you have an existing design you’re happy with, it is maybe slighly less important or noticeable.
But if you found you’d made a mistake along the way, or you wanted to do a 7 string bridge on the same design, or tweak a line or just generally experiment, when you go to change something you just have a bucket of random lines floating in space and you’re kinda screwed. Change one line and then you have to go down the line and change every other line because they aren’t really connected to each other. Usually though you’ll (I’ll) forget what I’ve done or why I did things a certain way and the whole thing is toasted.
Constrained sketches have a little red lock next to them. As you are making sketches, each one should ideally have the red lock. I’m not 100% on my designs but I really try to.
The weak point of constraints is the fix/unfix. The only thing you should use that for is for splines, which are hard or impossible to constrain. Occasionally I’ll use it if I can’t get something to constrain, but that’s weak on my part. It screws stuff up because it’s not really a constraint. Those parts can’t move.
there’s a command line in fusion and you can use it to find unconstrained elements in sketches. It’s very handy.
https://www.youtube.com/watch?v=matqB8nGzQIConstraints and the timeline also go together in a cool way. One of the great things about Fusion (no idea if it’s like this on other programs) is that you can slide back the timeline to an earlier part of your design, adjust something (like an extrude for instance) and then slide back on the timeline and the design should update, based on the stability of your design. Again, this is mostly for more elaborate designs with multiple bodies. This becomes hugely useful for modifying designs: say you wanted to put humbuckers in a strat for instance, you could slide back to where you extruded the pickup cavities, make a new sketch with humbuckers, extrude that, suppress the original pickups and then slide forward. If your design is stable, you’ll end up with what you want. Constraints are one way of making your design stable.
Anyway, I babbled again. I’ll try to make a video. Great job on the design.
-
I was looking at Stewmac today and notice their neck blanks are 13/16″ for Fender guitars, 3/4″ is still going to bite you though, 13/16″ is cutting it close and they are surfaced both sides, 7/8″ or greater, particularly from rough lumber is going to give you a bit of breathing room.
-
what are the advantages over Titebond? Just the UV dye?
-
have you ever seen these? They sound 1/2 between pretty good and exactly how you’d think they sound:
https://reverb.com/item/49883703-alcoa-vintage-aluminum-upright-bassreverb.com
Alcoa Vintage Aluminum Upright Bass | Reverb
Aluminum Corporation of America upright bass. Nice condition overall. Had a luthier fashion a bridge for it and install decent used strings. Has a label on the back of the bottom of the fingerboard - hard to photograph. There is … Continue reading
-
my question might have outted me as a slob.
-
it was something I picked up from Mike Kennedy about the time: unless you have some special method, you can’t really put in 2 sets of linings at once, so that’s 2 drying times per side. Also I think the sides come out much flatter laminating them against the mold (I guess similar if you were doing laminated sides) so there’s a lot less sanding.
But yeah, you have to resaw or come up with inner veneers and mill up the cores. And that probably did take me a lot of time, I batched enough for 3 guitars. The thickness sanding was endless.
I have found joining the sides to each other a lot easier too.
-
Have you considered a CF core? I haven’t really thought about it lately but we talked about that flax fabric core also.
But then in those cases you’d have to use linings and one of the best things about this is not having to deal with putting linings in. It’s a much faster construction method.
-
Not Michael but this is Jeremy Clark’s website,
https://52instruments.com/materials-and-design/
As far as I understand it, Sergei Dejonge more or less invented the idea but like a lot of Sergei’s ideas he moved on to the next idea. Jeremy and Michael Kennedy (both Sergei’s students) work together at Miles End Guitar Co-op and took the idea and refined it. They are both associated with it.
https://52instruments.com/materials-and-design/
I definitely don’t have the scientific vocabulary to describe it but for me the analogy is a drum rib, they are laminated and extremely stiff with the vibrating membranes being the top and bottom heads. In the analogy the guitar top and to a lesser extent the back are the vibrating membranes, and the stiffer the sides are the more stability the top has to vibrate and move air.
@anthony-kreher would have a much more articulate way to describe it.
Or, as was demonstrated to me by another structured sides guy, if you take a long carpenters hand saw and hang it over a bench, if you hold it loosely at the top and strike the handle, the vibrations will be weak and die quickly, if you push the end firmly against the bench the saw will have very clear vibrations and they will sustain longer.
I have only built one guitar like this so far but it was impressively loud with a complex tone and a really spooky “room filling” sound…I would describe it as having a “recorded” sound, kind of a like a speaker cone. I am 100% not sure if it was a fluke but I was an instant convert.
-
that’s pretty nice, have you had glue drips on them? Do they just fall off?
-
yeah I will do that. I need to do a tune up on it anyway.
-
In rereading your post I see a lot of similarities of thought.
I don’t have the math or physics to understand the measuring stuff at this point, but my physical understanding of that guitar from watching it is that the top is really compliant (in my mind, this means it moves a lot), to the extent that it really puts out a palpable amount of air when it’s played. I do think about the drum head analogy a lot. The more I think about it, the more I’m wondering why I would ever not use the cored sides. The only possible alternative to me would be some sort of thinner composite side (carbon fiber or flax fabric) that had comparable stiffness at a lower weight. But I don’t have a real understanding of how that would effect the sound, just that it would potentially make a lighter set of sides.
I have been wondering then about the back too and how that could/should be compliant as well. I wrote to Jeremy asking about that. As usual in talking about this my understanding is so rudimentary that I have to ponder his reply for a while. But he is using a braceless back, which is pretty interesting to me.
I think Jeremy differentiates between ‘push’ guitars (archtops, selmer style guitars, other guitars with a tailpiece) and ‘pull guitars’ (Martins, gibsons, guitars with pin bridges). Or something to that effect. It makes sense that they would have very different issues from each other, I think.
Without the math to describe things, I’m left to analogies…how is a guitar like a speaker cone? Is that a helpful way to think of things? Or like an amp cab? Perhaps a better analogy.
Anyway, thank you for your thoughts. I am starting to measure stuff for some classical guitars, I assume this will be a long process trying to understand things.
-
My understanding of the top thickness thing came from building two instruments, side by side. One had traditional ribs and a thicker top, one had the structured sides and a thinner top. The structured side instrument had a huge non traditional sound hole. The trad sides one had a regular D hole.
They both sounded really quite excellent but the structured side instrument projected insanely well and had a really peculiarly room filling sound. I can’t say I’ve heard a guitar that filled a room before like this one.
And I did notice some deflection on the bridge of the trad one. My thought is that there is probably some pressure that the top puts on the side with a tendency to splay them out (notably: this is a guitar with a floating bridge and a tailpiece so the pressure is exerted downwards, not like a pin bridge kinda guitar). So perhaps this is a special case but my thought is that with the structured sides, there isn’t the opportunity for the sides to splay out. There isn’t noticeable deflection in the structured sides instrument.
But my knowledge of all this stuff is super limited. I do know that that guitar kicks serious ass. I hope that I can make another one as good.
-
to be a bit blasphemous, I don’t really love a lot of the Selmer style guitars. It’s a bit of an odd situation because unlike Martin flat tops, Selmer hasn’t made guitars for 80ish years and I’ve never played an original. So it’s hard to say what the original sound really was. I have played a couple really nice French guitars from the same period. They are usually very bright with zero sustain, which is sort of the traditional sound but I don’t super love them.
What I liked about that guitar is that it’s a bit more midrangy, has amazing sustain and is just effortlessly loud. But it’s easy enough to make it bark for the rhythm sound.
Unfortunately I did no measuring on that guitar so not sure I can duplicate the stiffness of the original top. My friend is buying it though, he’s in town so I can get it back to measure a bit.
I just realized too that I didn’t take many pictures of the guitar. The construction was a little rough as I was just trying to see if it was going to work, so….no closeups. But you can see the soundhole in these pictures:
https://photos.app.goo.gl/6uehafhrdWAfsuRPAThere’s a bunch of videos of French dudes playing these guitars there….this is one of them side by side. Not sure the difference in sound really comes through on the recording.
https://photos.app.goo.gl/CTmGK6EZZnEQT1iX7
