Let's talk about the qualities of these parts, including what some will view as the negative stuff.

 

Not every builder is high on laminated parts; some of these guys will say you can't have a "true" archtop built of plywood, even if the bottom line is an instrument with an arched top. Probably many more builders, in the spirit of "whatever floats your boat" that has come to characterise modern lutherie, will agree with the notion of different archtops, with differing characteristics, played and appreciated by different musicians....we won't drive this any deeper.

 

Want to build an archtop? Want to skip the carving and bending? Me too, so I don't blame you. I was also interested in the notion (not originated by me - check the literature) of an archtop that is mellow, rather than one descended from an instrument intended to cut through an eighteen-piece big band. Let me hasten to add that there are a number of Luthiers, please note the capital L, who have tamed the cut. My hat's off to them. For some of the rest of us, there is another path.

 

PLYWOOD!

 

Sounds disgusting, no? Like something you might pick up at your local Cavernous Depot. Molded laminations is how I have come to think of my calling.

 

The advantages to forming tops, backs, and sides from veneers are many. You can build with any species your heart desires, pending commercial availability. You don't need to worry much about cracking, not a bad concern for the working musician to be rid of. The  heating and cooling seasons, not to mention humidity changes, won't be the issue they are with solid wood. You won't have to invest in a new kit of tools or skills. Time will be saved (of course you'll also bypass An Experience, not to mention the admiration of small children and dogs). If I think of any more I'll be sure to add them.

 

Enough with the good stuff, also known as The Hard Sell. On to the bad stuff, hereafter known as "excuses".

 

Two things; springback, and glue squeezethrough.

 

These parts are formed under pressure. They aren't heated or soaked first, so there is no slipping of the fibers through the softened lignin, the way a curve is formed when heat bending. Instead, the veneer slices are pressured into their new contour, and the glue does the job of the lignin; it holds the new shape when it cures, come hell or thermonuclear activity.  Heat-bent sides will try to straighten out if the lignin re-softens. These sides will not.

 

What happens is springback. This occurs when a laminated part is released from it's form, and it usually amounts to a few millimeters, no more than the tolerances most builders allow in their heatbending. It can also manifest as a minor twist, and when it does appear it is, interestingly enough, symmetrical in the right- and left-hand sides. In other words, it seems to be a function of the bookmatched grain on the show face. This is why we build guitars in an outside mold, so those little deviations can be gently overcome while gluing the top and back to the sides.

 

The other horror is the shame of glue squeezethrough. There is enough pressure on the stack of veneers, and here I'm speaking of the spruce as well as the hardwoods, to actually force glue through the structure of the wood; this is not a bad thing for the quality of the glue bond. Squeeze-through was once a bigger nuisance than it has become since the glue producer has developed a blocking agent to limit this effect.This was more noticeable on the surface of the figured maple than the straight grained maple, because there is a lot of end grain showing on the face of figured hardwood, sort of like bundles of soda straws.  Now squeezethrough will show (it it happens at all) as a few tiny scattered glossy dots on the show face.  These will powder off  with the application of 220 grit paper, and will have no effect on finishing.

 

Well, even the bad stuff seems kind of positive.