The Plywood Discussion

[Narcissism]

Look at Ibanez's Erogodyne bass. I don't actually know what they're made of, but I think their "scientifically resonate synthetic material" is particle board.

[kpcrash]

Look at Ibanez's Erogodyne bass. I don't actually know what they're made of, but I think their "scientifically resonate synthetic material" is particle board.

From Wikipedia:

Luthite is a light-weight synthetic material developed by Cort Guitars for the construction of bass guitar and guitar bodies.

Luthite was developed as a substitute for wood, for as a synthetic composite material there is much greater control over the consistency of production. Additionally it is able to be formed to almost any shape, i.e. 3D shapes out of plane, where the wood equivalent would require a very large body blank or laminates. It should be noted that, in spite of these advantages, it possesses considerably less resistance to impact than its wooden counterparts.This renders finished instruments more susceptible to being chipped during use or cracking if dropped.

The tone of luthite is different than many tonewoods, this may be seen as an advantage or disadvantage according to personal preference. It is best suited for slapping and popping on the bass, yet possesses a clean and even tone. Whilst primarily used in Cort’s Curbow series basses, the Ibanez Ergodyne series basses and guitars were also made of luthite until 2006.

Translated.... plastic I've seen one up close, looks like particles suspended in resin.

[psw]

OK...found something preliminary to my own experiments...

I have two interests in this lately...one is the use of a cheap alternative material that "might" have some benefits in making and design...so I am not looking at it so much from a "tonewood" position at all. In fact, I am thinking more how the materials qualities could best be exploited, how it could make alternative woods like birch usable for instance...

The other aspect that got me thinking about this kind of thing is the aesthetic qualities. I recently returned from Victoria's "limestone coast" and amongst other influences, there was something very attractive about the way complex curves and forms were created against the linear layers found in limestone. Immediately I was struck by the plywood effect and what happens when you carve into plywood...and of course my only real experience in this has been on guitars.

To give a sense of the kind of effect I am thinking (leaving aside all the tone and other considerations for a little bit), consider these kinds of effects...

As I was trying to suggest...the more radical the carving, the more pronounced the effect...

Personally, from an aesthetic material, I can see some attraction and potential and a lot of ways it could be used creatively...but it means abandoning something like a slab sided telecaster like thing and moving to something more radical and organic in form...possibly not a bad thing on a guitar and many shapes would lend themselves to such shapes (satriani's sucked lozenge thing for instance) or others could be conceived that were both exceptionally "ergonomic" in form and artistically pleasing.

Now...if one could make something that had it's own aesthetic qualities and combined it with the general opinion that the pickups and hardware have a predominant influence over tone on a solidbody...hmmmm

After all...a lot of people covert expensive spalted wood, much of which is extremely soft and structurally suspect...yet looks great and works in the right hands. Why should a composite material be any different.

I agree that there are probably tonal reasons and the qualities of plywood are not necessarily desirable (for a neck you want the longitudinal strength for instance)...but it could be made to work and the aesthetic affect pleasing, the materials sustainable and cheap...and whole areas of alternative making are opened up like building the whole thing from one blank as I am kind of considering...

anyway...I'll cut up some wood I think and glue it up and have fun with the sander on another day and see in fact how hard it is to make these kind of complex shapes in it

pete

[kpcrash]

Pete I'm looking forward to what you create and agree with you completely.

[psw]

Thanks KP...lets have a look at the aesthetic potential...ok, not making the guitar but I found a heap of really bad packing ply in the garage that was left be a previous tenant...so I randomly put it through the saw and glued up a couple of interesting blocks of "wood"...one I glued them up in a kind of spiral so there will be end grain, or not in every kind of direction...hehehehe

I even got to drag out my DIY book press...it uses a hydraulic jack...so it better stay stuck...

Sounds like fun...any suggestions on shaping tools...

pete

[fryovanni]

I think it is really very unfair to bring in "acoustic instrument lore" into this. The proposal is for a solid or at least electric instrument. An acoustic top requires flexability and the whole sound is produced by the materials ability to flex and react in complex ways and the art of bracing to control it. In a solid 2" piece of solid wood...much of this means nothing...and with so much relying on the electronics...the differences may well be extremely subtle.

Ferrington made a guitar that ry cooder bought (he liked it so much) that was a single piece of ply, extremely rough and thin.

...

If the pickups really do make such a difference, does it really matter what a guitar is made of at all. In whcih case...perhaps the testing should be focused on the pickups and not the material.

I'd like to hear if there really is much relevance (obviously there is a little) between the laws of a good acoustic top as referenced by fry and a solid body guitar...or are they essentially different beasts.

But there is a lot against working with ply in many respects and I am cooling on the idea a little in that regard.

The question of the importance of a solid bodies characteristics is very interesting and perhaps the real point here. If we disregard the material of a moment...what is the ideal characteristics of a body and neck structure for a purely electric guitar. Is it stiffness and strength, is it only longitudinal strength, is it something to do with the resonance...does chambering help, what does it do...are these things even significant in view of the importance the electrionics seem to place in the scheme of things. I am not sure that the answers will be found by referencing acoustic instruments...though maybe I am wrong...

pete

Pete,

I am not sure what your getting at. I am not compairing a solid bodies performance to an acoustic, nor trying to corrilate design considerations. I definately have no idea what "acoustic instrument lore" you are talking about. I made reference to some material testing that I had done with regard to spruce for soundboard use, but the reference was regarding general properties and deviation from bit of wood to bit of wood.

After playing with spruce used for soundboards, and really focusing in on natural ranges of properties from bit to bit. I have really come to realise some significant potential for variation. I have also recognised the significance of certain attributes that account for much of this variation(such as grain orientation, growth patterns, density and such). I would certainly say it is not a total crap shoot as to what properties you will get if you account for these notable features, although you still have smaller variations that are difficult to nail down. Actually, many of those features are also used to develop grading criteria for plywood to ensure some minimum performance garentee(although within much wider range of tolerance, for most grades of ply). I think with musical instrument wood there is a history of importance placed on selection of materials for this reason, at least with acoustic instruments where pushing the limits of efficiency and performance are highly valued.

I made the comments because of the testing that was being discussed. I do believe it would be helpful to think about some of the charictoristics(density, stiffness and such) if your going to try to compair the resonant responce of materials through testing.

If you look at my posts in a few recent topics relating to electric/ acoustic "hybrids" you would see I am not one to say acoustics and electric design and function translate easily. Actually, I am probably more enclined to say the two are based on such different systems they shouldn't be confused(although I do respect the opinions of people who find the acoustic design properties integrated into electrics often make for results they find very cool).

Kp,

Exactly my point. There are hundreds, maybe thousands, of entries on this forum and others where the mere mention of using plywood to construct a body is complete heresy. This makes it a very emotion laden discussion sometimes with the majority stating that unless a guitar body is made from (enter favorite wood here) it will not sound good.

You don't need to prove anything here, and unless you are doing this to try to understand the material better to suit your own curiosity, your pretty much wasting your time. As many of those negative plywood posts are out there, you will find as many other solid woods that are also put down for various generic reasons. You will find plenty of unfounded supporting comments for any number of woods or even laminate combinantions. Most of the time these are personal opinions. Even if you provided some silver bullet for plywood here today. In about a week or two you would see another negative plywood comment, likely something about glue killing or sucking "tone" with no foundation short of a strong gut feeling.

[Mattia]

Re: if it's all in the pickups, why bother? Because it's not all in the pickups. I think it was Perry who said something like 'every aspect of guitar design and construction affects how the instrument sounds. The question is: which bits make an audible difference?'

My experience and feeling tells me that yes, construction (chambered, solid, etc) and wood type certainly do make a difference, as does scale length, string choice, but pickup selection (and amp selection, the other half of the guitar as an instrument) make a huge, massive difference. Vintage-style pickups (lower output) and single coils seem to be more sensitive to subtler changes (wood choice, construction, etc) than active EMG buckers played through a rack of effects.

[psw]

My apologies if I misunderstood what you were saying there Mattia...no intention to offend. I had the feeling, or was kind of asking the question...in acoustic building there is a lot of importance on flexibility, lightness stiffness and bracing...it is something of a science. However, do those same things apply in a solid body to anything like that degree?

I agree, that everything does indeed make a difference and having worked a lot in the electronics area, I actually disagree that the pickups make as much of the "tone" as people suggest. Personally, things like the attack and decay of notes is a lot of what I hear...scale length also makes a huge difference to both feel and tone.

Certainly the wood makes a big difference, especially to the envelope of a note...a telecasters sharp attack has a lot more to do with the solid construction of the tele than the pickups on it...vs a strat which is substanially hollow, has a different bridge but the same scale length and similar materials...putting strat pickups into a tele does not make it sound just like a strat or visa-a-versa.

...

Anyway...didn't mean to put any input down, it's all interesting and valuable stuff...

Meanwhile...not supporting the plywood as a tone wood or it's suitability, I did spend a bit using power tools inappropriately to hack away at some "blanks" but there is a fair way to go with it...basically just messing about with carving and contours and seeing the workability and any other qualities I can getout of just messing with the material...

and here is a blank I have just started that had the 3 ply's rotated so the grain is going in all directions...or some kind of spiral effect...

Very rough so far...this is a mix of stuff I found lying about...the last one is actually the worst kind of ply imaginable...packing crate ply! But, it is good enough to play around with and get some ideas about.

This is not the kind of stuff you would build a guitar out of...or anything really...but so far it is very easy to work and is incredibly stiff and strong. The top one (both sides shown) was better quality stuff and two kinds, the outer layers seem to have a walnut inner layer, there appears to be some queensland maple in there as well...I think the lighter stuff is probably hoop pine.

The more radical the carving, the more radical the effect of course, the flatter the surface, the more "boring it looks...but there may be lots of interesting effects that could be created...so, so far...interesting

One thing of interest perhaps...with three ply like this, obviously you need to put a lot of layers together...but if glued in the same direction predominantly the grain is running in that direction and if using something like a maple face or other hardwood, you get mostly longitudinal hardwood, with a lighter often softwood between them. A lot of strength and stability and I suspect incredible drying (it is very thin layers pressed after all under heat)...You seem to be able to carve to quite thin sections without any risk of it being fragile and the thinner areas seem to be fairly resonant (although this is not really an exercise in that)...certainly it seems to have a stiffness regardless of how thin you carve it and resists flexing.

Still, as I say, this is an exercise in playing with the material as much as anything else...

pete

[Keegan]

Hmm, it would make a good cap for a Les paul or similar carved-top. Maybe convince people to stop using that damned flamed-maple top.

[psw]

hahaha...I dn't know about that...if you were going to do an LP wit a ply top...what would the rest be..MDF

It would give you an instant wired kind of bullseye design in the grain though.

With something like this it is exactly like a topographical map...each line is perhaps 3mm so any time it changes color or the line is wavy, your looking at either a concave or convex rise or fall in the profile. Something like a PRS top or something that is all curves like a satriani ibanez is going to show that off more. Something like the back carving on a parker would provide an even more interesting kind of effect...

This was the kind of thing I had been musing on...the the visual effect and because plywood provides the kind of strength and stability to allow thin sections without being fragile. Similar to chambering, you are removing material from the outside to provide lighter weight and resonance characteristics and potentially new form and ergonomics.

Still misgivings though...using cheap softwood veneers could still invite damage...parker get away with it by using a strong outer shell. Although parker do use finger joining to attach the neck and body seamlessly, you can see the potential in that pick of how smooth that transition could be. There is the notion that parker originally put out to use highly resonant light woods like ceder and spruce to promote resonance with the outer shell providing strength. With quality plywood, often the surface layers are hardwood like maple and the inner cores softer and perhaps having the potential for thin plates tied together and providing resonance if not in a huge solid chunk as it is traditionally used.

That is not to suggest that plywood is a superior material, I don't believe it is...I am interested in exploring what it does have to offer though from a number of aspects. Ideally, I think you would probably go for thin layers of selected timber in the same direction over conventional plywood, but this kind of stratabond stuff is available and creeping in to guitar building at the lower levels.

I don't think figured select woods will be going anywhere soon in the face of plywood but it is kind of fun to play with and would be great to practice on because the lines can provide a great visual reference, as I say, it is exactly the effect of a topographic map and the surface contours look exactly as the feel.

[kpcrash]

While probably impractical, I think pete's plywood "art" would look cool as hell as a fretboard.

[psw]

Actually KP...that's an interesting idea...you could make a fretboard out of layers of thin hardwood veneer...how about a rosewood and maple for instance...then radius it. Probably only get a bit of a maple stripe along the edges...although if you sanded through the top veneer enough...

I bet you could laminate a fretboard, maybe even close to 'conical' if you wanted if you glued them up over a mold...the top of the board would look like the wood you chose...but the edge would have a cool striped binding like effect. Of course the bottom wouldn't be flat anymore...hmmm. Maybe you could piece together a fretboard blank with different timbers as fret markers with the under layers holding it all together...or do something neat with inlay techniques.

On that first "art work" the more attractive ply on the outer layers with a darker core and kind of dark lines around it....that was a higher quality ply it would seem with what looks like walnut as the centre core and perhaps maple on the outer layers...the dark lines are the glue lines.

The paler wood at the back I think the darker pinkish face layer is Queensland maple while the light stuff is likely hoop pine. Layering in three ply, the outer layer direction predominates so you get roughly 2 in 3 layers in that direction to 1 in 3 the other way. In this blank I sawed it so that the predominant layer (the darker ones) are across the grain, but because the surface layers had been sanded so thin to finish, it worked out to be about the same in each once glued up...the lighter core layer then goes top to bottom.

I did find some guys who make plywood to order and I bet they would be prepared to use whatever veneer, in what ever direction you wanted if you paid them enough...but it is likely pretty expensive...more expensive than an 8x4 piece of dried figured maple or something...is such a thing could physically exist...probably not, but still you would have to really like this kind of effect to want to take the experiment that far. I think you could make a fine guitar out of it, but you would have to be very keen!

[kpcrash]

So... in the meantime... while I wait for my birthday and Christmas to pass in the next few weeks and see what kind of tools I get this year (hopefully some stuff that will help with my testing) I've got quite an inventory of "scrap" veneer from my father-in-law who used the various materials on his grandfather clocks. I figure based on pete's inspiration, I can stack this stuff at least 1" thick. If I have enough to make two 1" "slabs" I could have some fun with the sander and see what happens. In this mix is some burl maple, purpleheart, bird's eye maple, cherry, pine (or poplar) kinda hard to tell, sapelle, mahogany and walnut. Most are 1/42", the rest are 1/50". I suppose to really add some flair, I could dye the pine/poplar and just have some fun - not worrying at all about tonal quality - just that the stuff pete's doing looks so damn cool, I want to give it a try. The rest of the pieces that are not scrap (to me) will find their way onto something in the house... like... maybe it's time to update my desk. Hmmm.....

Sorry - went off topic a bit, but to get a phone call saying a bunch of veneer had just been dropped off at the house tends to bring out my short attention span.

[DC Ross]

Carved laminations can be very striking. Gunsmiths have been doing it for years, check these out:

[psw]

I did hear that....guns and bows use it for it's improved qualities, qualities that would suit guitar making I would presume...it should be noted that these laminations all run in the same direction unlike "plywood".

I never saw an example though...yes, they are striking and again, with a radical carve it could work well with a guitar aesthetically. You really do need to get pretty radical with it to get the effect though...fortunately with lamination or plywood you also get a lot of strength and stability with the technique to get as radical as you like. Without such carving you really aren't going to see it except at the edges and it looses a lot of the point from an aesthetic angle...you may as well use a solid piece of wood...unless you were to lay it up on edge...but then it would be more a stripy effect.

I think a neck made with thin laminations in this way could look very cool...lots of curves in a neck profile...unfortunately an area where normal plywood would be a poor choice unless it was heavily reinforced (such as laying up with CF). If you made your own plywood laminations where all the grain was in one direction, it may be very similar to normal wood, have a similar visual effect and be extremely stable. Making it yourself though may be a bit of a problem and possibly costly with some veneers.

Nice to see the effect though...thanks

[kpcrash]

A new monkey wrench appears....

Spent some quality time at the local millwork shop last night. These guys have been around since the late 60's and have seen things come and go, thus providing some interesting anecdotal knowledge on all things woodworking - and a shop FULL of wood from decades of building cabinets and furniture. On a humorous note, they asked me a few questions about building electric guitars and as soon as I mentioned using calipers to measure something they laughed and said that was too much detail for them . All kidding aside, we started talking about plywood and laminates. They showed me how some of the domestic plywoods were constructed and what "they" considered furniture grade over construction grade based on feel and sound. We then looked at some imported plywoods, mostly from the Far East region. There were numerous voids and sheets would be off square by as much as 1/4" on 2 or 3 sides. They expressed their disgust and frustration with this in very colorful terms. We actually took a few pieces apart and tried to identify all the layers of "mahogany" plywood which consisted of 7 layers (at 3/4" total thickness). I asked them to further define "s**twood" We actually found cork, and mostly pine/poplar/"whitewood". In some of the pieces we looked at, for example a piece of imported maple plywood, the alternating layers were 1/8" chipboard. One of the guys joked that it wouldn't surprise him at all to start seeing the inside of plywood be nothing more than recycled newsprint or cardboard in the near future.

So... what did I learn and why am I writing this? Because, there are WAY too many variables going on to be able to accurately test plywood vs. solid wood. However, there is sufficient control to test laminates vs. solid wood - but we all know that one already. So, I'll change gears a bit and dedicate this to the artistry and structure of using plywoods for now.

[Hector]

What's wrong with plywood?

...the middle piece cross-grained...

there you go.

[fryovanni]

Kp,

I am glad to hear you found some answers, and that you have not given up on laminate construction. There are some great design concepts such as using lighter, less stiff but resonant core woods with denser, stiffer and more durable outer laminates that offer some great strength(directional) to weight advantages. Combine that with the artistic oportunities, and it would be a shame to discount laminate construction.

[Ilikes2shred]

Wow those gunstock things look amazing. They kinda remind me of this thing I used to do with crayons when I was little. You would take a page and color it all rainbow-like, then go over the top with black. Then you could scratch through the black with your fingernail to expose the colors and make drawings and patterns.

I think someone would have an amazing result if they piled the veneers on top of each other, Then carved out patterns and accent lines for their guitar, much like you can with the crayons. They could even add multiple veneers to the headstock, then carve through them to make their logo. Maybe someday...

[kpcrash]

I'm actually thinking of doing this ES-335 style. Just a thought right now.

[psw]

Well...

There is plywood and then there is "plywood". A lot of fancy faced stuff used for wall paneling is only for effect, so an ultra thin veneer over 1/8" MDF is a perfectly reasonable proposition. Just about anything in packing crate ply is probably acceptable... similar with ply made for frame bracing too. But there is superb quality ply if you want to pay for it!

The cross ply thing is an issue, unless you can find a reason to justify sacrificing longitudinal strength for all over stability and uniform stiffness...certainly it is likely to be a damper on vibrations to some extent...with a neck there may well be significant problems, especially if used flat...although laminating has always been a good technique to avoid twisting inherent in really wood in such structures.

If you look at plywood as a laminated and composite material and not necessarily even cross grained...there are potentials as in fryovanni's above post...and aesthetically too, there are some creative potentials. There is even potentials for using materials not commonly used like cedar and spruce, even balsa which is light resonant and strong but easily damaged due to it's softness.

With the electric guitar and with many exploring chambering techniques to provide for "structural resonance" even more of the material used for a body becomes secondary...much is chosen for appearances anyway...IMHO...a 335 shows that a perfectly good high end electric guitar can be made with plywood after all with this chambering notion in mind.

But yes...you do need to be very selective with this kind of material for sure

pete

(happy BD KP)

[kpcrash]

Thanks pete and fry! Honestly, I thought of the 335 style because instead of using a laminate to mold the curves in the body - I would use a laminate and carve it as pete did in his test samples. I have quite a selection of thin veneers right now and just need to pick up some good adhesive. I have another body shape in mind... but I digress, more along pete's influences, but I can't even draw it at the moment. Thanks again for providing valuable feedback on this thread. Any suggestions on the adhesive? I'm thinking anything not water-based that I can get plenty of, or thins easily so I can quickly roll it and add layers. I figure I make a makeshift press out of a 250lb piece of flat iron I've got (24"x24"X2"). It was originally made by my brother-in-law as a backstop for his shooting range, but decided he needed something bigger - so it's been sitting here as a press for years.

[psw]

Yeah...that could look really cool...even if it were stuck to the top of a solid body as a top would be kind of neat, but you do need to make a pretty deep kind of carve to get the most of the effect.

Pressing it is going to be a problem...veneers can bend and split or bubble if insufficient pressure...some chipboard with some plastic down might make a good pressing boards...a lot of bricks might do something...if the pressing boards are string enough and you have a falt bit of driveway, park the car on it overnight...that ought to press it!

On these test things I used normal white pva wood glue...seemed to hold up fine...use plenty of it and it sould hold up ok I would think...mine seemed fine and I did a rush hack job...I attacked mine with a power plance on maximum cut and if anything was going to delaminate that, you'd think that would...ahahahah...anyway, if wood glue is good enough to hold a normal guitar together, it will surely hold these laminates in a non load and huge surface area together fine.

You could make a solid blank...or, you could so cut it so that the arch is already roughed out with the laminations...pressing though would be a problems of course if you do this...but it is an option to save materials and a lot of carving. It is one of the ideas I have with my thinking of processing a radically carved guitar from laminates...a lot of the carving would be roughed out with layered templated laminates.

If you spend quite a while imagining your design and how the laminations might look in 3D...you might also consider leaving three laminations at at the bottom to provide a faulse binding or something around the edge...loots of cool potentials I think!

[fryovanni]

Vac. Bag is probably your best bet for laminating thin woods, especially if you are forming up a shaped part. You really don't need high clamping pressure, you need even pressure. The vac. bag system also allows you to use shaped back forms, instead of top and bottom forms with clamps.

[nuge67]

While I don't have anything scientific to add I would like to say that I've used plywood a few different ways on my guitars. I like to build semihollw guitars. I've actually never completed a solid body. The tone from a solid body just does nothing for me. But I digress. My 1st several guitars were tele style semi hollows. The top and back were mahogony ply and the core was whatever wood was lying around. Most often poplar, but on a few occations pine was the core wood. And I have to say the mahogony ply (which realistically was probably only mahogony on the 2 top surfaces) with the pine core provided incredible tone and great controlled feedback. My main guitar I play now is 1-7/8 thick. Only the top 3/8 of an inch is solid wood. It is antique Mahogony from a 100 year old table. That guitar has 3 cheapo single coils from guitar fetish ($15.95 for 3) wired in series. The tone is impecable. No one can beleive it is mainly plywood. Its furniture grade birch plywood. Why do I like to use it? Because I build furniture for a living and often have a lot of otherwise useless scraps of plywood laying around.

Now the plywood neck thing interests me. I was thinking about this before I found this forum.