Cab joints strength...

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Aurora
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Cab joints strength...

Post by Aurora »

How do you guys assemble cabs - heads, combos or speakers alike...
Traditionally, dovetails seems to be the preferred method, but several joint tests made on YT clearly indicates that common miters makes the strongest glued joint... can even be reinforced by some dovels in booth direction...
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Raoul Duke
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Re: Cab joints strength...

Post by Raoul Duke »

I’m set up to do 3/8” half-blind dovetails and use them for pretty much everything at this point. I think they’re plenty strong enough for everything I build (heads to 2x12 combos and everything in between) and they look great on natural finish cabs (about 30% of my work).

Used to switch to 1/2” box joints for covered cabs, but I’ve gotten pretty familiar with the subtle adjustments to the jig and get joints to fit just right pretty quickly - so it saves me time and aggravation which I think is well worth leaving the jig set up for one style.

Cut your stock accurately, tweak the jig as needed, and everything comes out pretty square with very little adjustment required during glue up.

Hope this is helpful👍
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jabguit
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Re: Cab joints strength...

Post by jabguit »

Dovetails are strongest based on glue surface area and the wedge effect of the tails' shape.
But a basic miter (cleated) can be strong enough, using an adequate adhesive. I prefer urea formaldehyde as it dries harder than any other adhesive I've tried - and in a half century I've tried most.....

cheers,
Jack Briggs
Briggs Guitars
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Aurora
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Re: Cab joints strength...

Post by Aurora »

I absolutely agree that on a natural wood cab, dovetails looks the best.... on the other hand, for a tolex covered cab any joint will do, provided it gives enough strength...

This is one of the tests I mentioned.... fairly well documented, too... this ink also gives you links to similar tests - for those interested...

https://www.youtube.com/watch?v=CE147Ow7RmM
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Aurora
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Re: Cab joints strength...

Post by Aurora »

I absolutely agree that on a natural wood cab, dovetails looks the best.... on the other hand, for a tolex covered cab any joint will do, provided it gives enough strength...

This is one of the tests I mentioned.... fairly well documented, too... this ink also gives you links to similar tests - for those interested...

https://www.youtube.com/watch?v=CE147Ow7RmM
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Phil_S
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Re: Cab joints strength...

Post by Phil_S »

If you are looking for simplicity, try a locking miter joint. It's strong enough. The only drawback is getting the setup right.
Bill Moore
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Re: Cab joints strength...

Post by Bill Moore »

I know biscuits are not the traditional joint, but I've had good luck with them. Been several years since the initial build, and no problems, and pretty easy to do.
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statorvane
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Re: Cab joints strength...

Post by statorvane »

I have used blind rabbet joints on numerous head cabs and several speaker cabs without issue. Fairly easy to make with a router table or table saw. I have found that Gorilla glue works pretty well for these as well as traditional Titebond. These are all tolex covered. These joints do not look as good as dovetail joints.
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cbass
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Re: Cab joints strength...

Post by cbass »

Drawer lock or lock miter is the way to go. It makes assembly easy. It's easy to repeat. I don't care for the look of dovetails. Also they are more likely for the glue to fail from expanding and contracting against opposing grain.
Gorilla glue is terrible in my opinion.
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didit
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Re: Cab joints strength...

Post by didit »

cbass wrote: Sat Dec 28, 2024 12:38 pm Drawer lock or lock miter is the way to go. It makes assembly easy. It's easy to repeat. I don't care for the look of dovetails. Also they are more likely for the glue to fail from expanding and contracting against opposing grain.
Gorilla glue is terrible in my opinion.
Agreed fully, however absent a router table plus a few hours of setup and then practice it's kinda out of reach. I get reliable success using just a "job-site" bench saw with a simple kerf width slice of the face of one board at the depth of the other board's thickness (aka the single rabbet joint), and then glued up with Titebond III. Does require organized care clamping to get things square all round. Modern PVA adhesive !!! Gorilla has uses, just not here. These joints are best with Titebond or equivalent -- level III is best in my experience as it's toughest and also quite easy to work with.

..
Snicksound
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Re: Cab joints strength...

Post by Snicksound »

Aurora wrote: Wed Dec 18, 2024 10:53 pm How do you guys assemble cabs - heads, combos or speakers alike...
Traditionally, dovetails seems to be the preferred method, but several joint tests made on YT clearly indicates that common miters makes the strongest glued joint... can even be reinforced by some dovels in booth direction...
After I realized that most big name OEMs use simple butt joints, I stopped worrying and went with that. Have yet to see a cab fail or buzz.

In recent years I've started adding "dados", mostly so they are easier to put together (easier to glue something when it naturally wants to hold that shape). I "dado" the baffle in too, Mesa style. Built a few 1x12 this way that can take a 100W head without a sweat.
No special tools, just doing on the table saw.
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cbass
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Re: Cab joints strength...

Post by cbass »

I mean routers are pretty cheap.the bits are cheap. You can make your own table if you want. Setup shouldn't take more than a few minutes. Save your pieces once you get it setup and use them to setup for the next project. I'm not saying doing it on a table saw won't work. It's just a lot more work.
I like regular titebond.
I'm lazy ass carpenter and i don't like to work any harder than absolutely necessary. I like to figure out fast and easy ways to get stuff done so I can spend most of my day hiding in the portajohn drinking and smoking.

Edit: I was talking about doing box joints on the table saw being more work. A simple rabbet joint is plenty strong and easy enough. I really don't think it matters much if the cab is getting tolexed especially if you're using quality plywood
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