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Has anyone here done a Manzer wedge? Any tips? Hints? Step by step video instruction?

Thanks in advance

Steve

Sorry for the double post.

Morning Steve,

I do it on almost everything I build. Call me in an hour or so if you want to talk about it in person. (Easier than typing)

Cheers, M

Once I started building with a Manzer wedge, five or six builds ago, I also done it on every build. I've only found two "issues." The first is to remember to always reference to the soundboard. On a traditional build that's not an issue as the soundboard and back are parallel. When building with a wedge, it is. The second item to note is to assure that the binding channels are fully implemented. That's more challenging when building with a Manzer wedge as the wedge angle adds to the doming angle of the soundboard and, more importantly, the back. I use a 12 foot radius dome on the back and, when coupled to the angle of the wedge, that makes the angle between the back and the bass side quite significant at the extreme of the lower bout. Some careful work with a safe file is required. I've built with a wedges from 0.75" to 1.5". It all works, though the extreme wedge might be an issue for playing while standing.

I tried it once, but didn't like it. Every degree of tilt is another degree your left wrist has to bend in order to keep your hand in the same orientation relative to the strings.

Firstly, make sure your sides, and neck and tail blocks, are deep enough to accommodate the wedge you want. I make both the same depth, and tip the body on wedges to mark it with a block and pencil on back radius dish to get the correct depths at neck, tail, and sides. I just remove the excess with a plane/spokeshave before "driving the bus".
Other part where you need to be a bit ahead of the curve is the binding channels, as Hans said.

Don't see how the doming angle of the soundboard is "added to" compared to a non-wedged body. - ?
But the back, definitely.
My first wedge build went reasonably easily using 2 mm thick Indian Laurel bindings.
With my latest wedged OM, same amount of wedge, I found the change to a 12' back radius (from my older 15') made it even more tricky to fit bindings. Filing or scraping binding channels is definitely required whatever the radius (see Dan Erlewine's Stewmac video for suggestions) https://www.stewmac.com/video-and-ideas/online-resources/how-to-install-and-repair-instrument-binding-and-purfling/making-a-sharp-edged-razor-file-for-binding-channels.html
This time I used Bubinga bindings at 1.5 mm knowing it was very stiff, and after routing off my first (failed) attempt, I bent another set on my iron being very careful to get them to fit as close as I could get them.
Even then the twist in the bindings required due to the wedged back at that radius necessitated very firm clamping, especially on the cutaway section.
Next one will be plastic bindings!!

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Colin noted "Don't see how the doming angle of the soundboard is "added to" compared to a non-wedged body. - ? But the back, definitely."

You're absolutely right. (While I was only half right.)

I make a 'Smith wedge': he patented the idea back in about '69, iirc, but it didn't catch on. Linda, of course, had never heard of him when she independently invented it, so she deserves the credit for making it popular, at least.

I have a strong shop rule: never make a guitar you can't buy a case for if you can help it. Check the depth of the deep side to make sure it will fit your cases.

Other than that, and the few issues with binding and such that have been mentioned, it's the easiest 'ergonomic' mod, much less of a production than an arm rest bevel. Even a small amount of wedge, say a 1" difference between the treble and bass sides, is very effective, being about the equivalent of reducing the width of the lower bout by an inch, IMO.

I've been kicking around trying one of these. So, if you reduce the depth on the bass side, do you add it to the treble side to keep the volume of the box similar?

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Tony Thatcher
Bozeman, Montana

Yes, that's the idea.

I've done one with a 1" difference . 3.5" -4.5". Yes, you do have to mind the heel and tail block.

I had a Dickens of a time with the binding on the back. Trying to file the channels did not seem like a good solution. Like, how do you file the waist portion? I ended up removing almost all of the inside corner of The binding to get it to fit tight. Not eager to try that again. Although I might try something with a smaller difference, maybe half inch.

Pat

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Pat

If the neck block is supposed to be 3-5/8” and the tail block is supposed to be 4-1/8”, that becomes the axis. In other words those measurements don’t change. I do a 3/4” total maximum difference on everything, so 3/8” per side. Making the bindings less tall also makes installation easier. Lightly beveling the bottom edge of the binding/purfling helps. I lay the pre-bent binding w/purfling up on the bench, mark up the surface of the purfling with a white pencil, wrap a 4”x 1/4”x 1/2” stick with P150 stikit paper, rest one end of the sanding stick on the beach top, the other on the inside of the binding w/purfling and sand until the white is just gone. No channel filing necessary.

My method uses brown binding tape, CA w/accelerator (satellite city hotstuff), and a 24” cam clamp and abs pipe culls for the waist. The clamp is also handy to pull in the odd spot that you can’t draw in with the tape alone.

I’ve done this on at least 45 guitars. It takes a bit of practice but has always worked well for me..

M