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I'm making a Manzer wedged cutaway, and know I will face a challenge when it comes to getting square, even depth binding ledges all the way round on the back.
I'm thinking a shop made scratch stock to even up the bottom of the binding ledges, cut first by my tower routing jig.
Looking for suggestions, especially pics, of one someone has used, or seen on the net - I've had no luck so far.
(EDIT)
I just remembered seeing something about evening up binding ledges with a wheel gauge. Like a wheeled marking gauge I think - anyone got details/pics?

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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.

What is a scratch stock?

Do other people doing wedges with cutaways encounter problems?

Why do you think it will be a problem?

I too have thought of this. I made a tool to score the top. Got it from a youtube video, but design similar to what is shown many places. It suggested turning the blade, made from a saber saw blade, upside down and grind a scraper on it.

A scratch stock is a woodworking tool used for applying decorative treatments, such as beads to furniture and other wooden items. They consist of a handle of some kind, with provision to clamp a steel blade into which the profile of the shape to be cut has been filed (rectangular in my case) and you scrape (scratch) rather than cut, the unwanted wood away.
e.g. https://www.youtube.com/watch?v=G7BJQjuDVgU

Why do I think it will be a problem? -

Using a tower binding router, (and other types) with a doughnut riding on the back and the cylindrical nature of the bottom of the cut by the router bit there are variations in both the depth of the ledge cut and the shape of the binding ledge bottom (slightly curved instead of flat)
This is due to both variations in angle at which the domed back meets the sides at different points around the rims, and the router cutter leading, or trailing, the point of contact of the doughnut with the back, both of which will be much accentuated with a wedge.

_________________
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.

We tossed out donuts, and instead use a shop made widget whose high point is right next to the cutting edge of the blade. This greatly helps with keeping the channels even.

What do other people that do wedges do?

Colin, you can use old saw blades, card scrapers or a wide bandsaw blade.
FW has a couple of articles in the archive on this very topic.

B

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My memory is so good, sometimes I remember things that never happened.

I've done one wedge and I had a dickins of a time with the back binding. I finally cut the inside corner of the binding all the way around until it would go in good.

Ed, got a pic of that widge?

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Pat

Tomorrow...

[quote="pat macaluso"]I've done one wedge and I had a dickins of a time with the back binding. I finally cut the inside corner of the binding all the way around until it would go in good.quote]
That's something I do routinely on non-wedge bodies (and many others form the posts I've seen on the subject)
Also I ground a small file end and used it as a scraper to help level the bottom of the ledges.
But even then depth variations are still slightly noticeable when binding, especially the back near the neck block.

_________________
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.

We use a Titemark cutting gauge or a Veritas wheel gauge to even out channel depth after milling. On a tapered body, binding jigs that reference depth off the top or back with a donut guide assembly will mill a progressively shallower channel as the angle of the local top/back referenced to the jig's horizontal increases. For most guitars, this means that the back binding channels from neck to about 2" past the waist will be noticeably shallower if not adjusted. The Titemark is the easiest to set and use, but a relatively expensive (but very well made) tool compared to the Veritas or similar knock-off wheel gauges.

We don't worry about the cutter not being square to the sides during the cut - the error is small and the binding edges are beveled, so we get a clean, tight fit.

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A constellation only takes shape when one maps the whole.
- Beth Brower

Thanks Woodie!

_________________
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.

If anyone's interested, found a simple scratch stock for this purpose here http://www.sawmillcreek.org/showthread.php?148247-A-simple-guitar-binding-scratch-stock-G-Wilson

_________________
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.