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Does the Cumpiano workboard have to be 1.5 inches thick? Let's suppose I made it from red oak can I make it thinner, say 1/2 or 3/4? I did notice in a photograph he's got the neck support overhanging his bench so there's a rigidity issue. Is there some reason, something I'm missing?

Thanks,

-jj

It doesn't have to be. You just don't want it flexing too much. You could always run a 1x2 down the center to stiffen it. Maybe two so it sits properly.

That will also raise it so you can get clamps underneath.

Thanks for the response!

-jj

Cumpiano dosn't even use the work board anymore according to updates on his site - you may want to consider building as most do with an outside mold.

I've been reading up on outside molds and this has opened up a keg of questions. I have been confused at the concepts of the 1.5 degree slope from waist to shoulders and how this was done on a workboard with the guitar upside down, I see now that the mold facilitates this.

I suppose there's many other advantages to the mold that I'm unaware of but I'll trust your experience and set down the path of a mold.

Can you tell me the best link for a mold to copy?

Can I make it out of hardwood? With my handtool and bandsaw only workshop cutting plywood isn't ideal. I can cut rough edges with the bandsaw but getting to the line requires the use of a cabinet makers rasp and i don't want to dull my rasp.

If it makes any difference I'm planning a OM Florentine cutaway.

Thanks,

-jj

A good way to make a mold is to have the guitar shape 1/2 master template about 2" wide all the way around. Drill a couple of pilot holes, these are used to pin the template to your blanks. Mark the blanks 6 or 8 depending on how deep you want the mold --- I believe LMII and SM use low density fiber board. I/we (KMG) prefer MDF seems more stable. Cut the blanks a fraction over size on your band saw -- then by pinning the template to the blank and using a bearing guided flush cutting bit in a router, you can produce perfect copies of the template profile. Stack and glue -- done.

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Ken Cierp

http://www.kennethmichaelguitars.com/

To answer your original question, I use a double thickness of birch plywood. I found the workboard easier to work with by putting some feet on the bottom; makes it easier to work with clamps. I sometimes use an outside mold to help me get things lined up properly, but since I started using a bending machine, I found that I can usually build without an outside mold. You'll find as you go along that you'll develop your own approaches, but getting started I followed Cumpiano then adapted as I went. I pretty much like working with birch plywood, and don't find it expensive considering how often I use my forms/molds. Excuse the mess on my work space; it's generally not that cluttered.

I love those dumpy legs under the workboard, so cute!

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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.