Official Luthiers Forum!

I am going to build an archtop from one of the Acme laminated tops & back.
I am trying to find out the depth of some of the classic insturments from the fortys & fiftys. My memory tells me insturments like the super 400 & Johnny Smith Gibsons were in the 3.75 " range. So far I can not find any specs on line to confirm this. Does anyone know? I would also like to put an oval hole just below the neck like my old 1966 Epiphone Howard Roberts model, but I have no idea if I can do that with the Acme top?
The Acme tops are a 3 piece lamination of.050" each. I would like to get this as thin as possible. How thin are carved tops typically?
MM

_________________
Mike McNerney

RE ; 17 inch carved tops general numbers.

The perimeter re-curve areas are about .125 to .25 in the center for X braces
and .125 on the sides , .165 on the ends and .195 in the center for parallel. This is for spruce..cedar go a bit thicker. Lutz can go a tad thinner in the recures.

The backs are usually around .125 recurves to .195 in the center.

At any rate me woulden't take much more than .125 off of either side. in the recurve area.

Me gotts no idea about plywood plates other than

Re rib widths...
anything much wider than 3.25 and the top end starts to becomes thin and weak not to mention its getting kinda big to hold.
anything less than 2 5/8 produces a weak voice instrument lacking in the depth and richness of an arch topper.

Depending on the size and position of that oval will determine if you gonna go with parallel or X's. Of course you could always use bent braces but you really gotts to know what your doing.

Even though me hears tell they are good tops, you can do what ever you want with that Acme including burning it.

thus spaketh ?adma
blessings

_________________
.

Audiences and dispensations on Thursdays ~ by appointment only.


.

Padma's covered most of it. I've never gone over 3 1/4" O/A (ie 2 15/16" sides), but 3" is probably more typical. Not sure if historically accurate though.... Triggs makes a great repro of the Stromberg Super 400. Maybe check there for actual side height.

_________________
Dave
Milton, ON

I would think twice before carving anything away from the Acme plates. Most laminated plate guitars are not graduated but left full thickness.