Laminated Bodies

[auscab]

Ive been thinking of doing a laminated body from .6 veneers at some stage in the future.

And I have been thinking of either a three layer or a four layer.

I don't want to do what I have seen on cheap laminated jobs where there is an inner and an outer in the same direction with a thicker filler at 90 degrees in the middle.

If I do a four, I would do one outer in the normal grain direction for a side, the next could be 25 degrees off center to the left, the next 25 degrees of center to the right, and the last ,the inside straight again.

I know you can see cheap guitars that are laminated. But I have also heard that it is an accepted method with some classical builders, and that silk has been used in between layers.

Does any one know of a link or a blog of this being tried ? laminated .6 veneers in any form? I don't do much browsing around classical build forums.

PS. with a solid top

[Tod Gilding]

I wouldnt mind laminated sides Rob, but I don't think that I could bring myself to build with a laminated back or top

[nnickusa]

I've got a plan drawn from a Ramirez, and It's got laminated sids, at least. I'll check tomorrow to see if the back is as well....

[Mike Thomas]

Most Selmer and Selmer Maccaferri guitars had laminated backs and sides. Standard veneer back in the 1930's was, I believe, a bit thicker than nowadays, around .8mm, and three layers were used. Typically the outer was Indian Rosewood, the middle Poplar (at 90 deg.), and the inner was Mahogany. This was clearly not done to cut costs. In fact nearly all the first year's production was sold by the Selmer shop in London, and you could have got a couple of major brand American steel string guitars for the price of one Selmer.

[auscab]

Thanks for the info.

I'd be interested to see what your plan says Nick.

Tod, tops for sure , I don't know about backs though. I suppose the answer to that may be in Trevor's book ?

Thanks Mike , very interesting ! I will have to get the book on the selmer guitars soon.

I was also thinking about it from other interesting points . I had a friend telling me how cold moulded boat hulls made this way made some of the strongest and lightest hulls.
And one of the fastest and hottest interesting bombers in WW2 was the Mosquito Bomber. made the same way.

The two sides I bent some time back in the picture have been sitting outside, under cover. The one sitting on the Uke mould is three layers of .6 with the grain running all in the one direction and has kept its shape well. The one in front is solid and was bent with a blanket. [ It reminds me of the Ian Dury & the Blockheads song " I want to be straight " ]

I'm not trying to have a go at good old solid construction here. It's just interesting information to consider. there are two ways of looking at laminated back and sides , the cheap nasty method, with rotary cut veneers and the high tech lighter stronger possibilities with good quality veneers. And all sorts of design possibilities with the way its pressed. obviously, some of the best timber to be had gets sliced into veneers as well.

[Tod Gilding]

Yeah Rob I was thinking about Trevors designs with that statement (live Back ), although I don't recall ever playing a laminated back that I thought had a nice tone,but they have all been factory built instruments and cheapies , I have heard the factories refer to it as HPL ( High pressure laminate) these days,not sure what the difference is, However I will be interested in following your build, as they say,you never know until you try it.

[Kim]

I have heard the factories refer to it as HPL ( High pressure laminate) these days,not sure what the difference is

I believe HPL, as in what many CF Martin entry level guitars are made from, is a phenolic product very much like regular laminex. Not too sure if the wood component of the lay-up they use is actually 'very' thin wood veneer or a photograph as per every Asian guitar you see these days with a highly figured top. But then either would have about the same tonal impact so I guess it doesn't really matter.

On laminates that we can do in our own workshops, I understand our own Bob Connor has been building with laminated sides for sometime now and I doubt very much he wouldn't be sticking with it if he didn't think it was a good thing. When you couple that with Ervin Somogyi's preference for stiffness in the sides, and Rick Turner's advise too, and then add Trevor and Girard's mass maths to the equation, then there's every reason to suspect that there really is something going on with strong stiff sides that is tonally significant.

Cheers

Kim

[Allen]

Don't forget Greg Smallman is a big fan of the laminated back. And it's bloody thick at 8mm I believe.

Liam builds his ukes with laminated "double" sides.

[rocket]

My last six builds which include acoustic archtops, hollow body electric arch tops , and semi hollow electric guitar and a bass all have laminated sides and the electric arch top has a laminated back.
As far as acoustics are concerned the laminated sides work really well, less side bracing gives a smoother line inside the instrument and the sides are much stiffer, i prefer this method over the conventional one thickness method for the afore mentioned reasons and also it allows me to bend sides around tight radii much easier.
Rod.

[auscab]

Don't forget Greg Smallman is a big fan of the laminated back. And it's bloody thick at 8mm I believe.

Liam builds his ukes with laminated "double" sides.

Allen, 8mm !! That is a strong back .

My last six builds which include acoustic archtops, hollow body electric arch tops , and semi hollow electric guitar and a bass all have laminated sides and the electric arch top has a laminated back.
As far as acoustics are concerned the laminated sides work really well, less side bracing gives a smoother line inside the instrument and the sides are much stiffer, i prefer this method over the conventional one thickness method for the afore mentioned reasons and also it allows me to bend sides around tight radii much easier.
Rod.

Sounds good Rod.
Have you ever had to but join the veneer together for the internal layers ?To extend the length of them, or seen it done?
I saw a youtube clip of stitching veneers together with glue possibly, on some machine.
It's a bit thin for just a but join, maybe it could be strengthened with a thread that gets compressed flat.
If I do it of center only 25 degrees I could get it out of one piece, but to do the internal"s at 90 it would probably need to be lengthened.

[Mike Thomas]

There is no problem joining the pieces of the internal lamination with a butt join. Glue the pieces together with whatever glue you normally use, Titebond, LMI glue etc., hold them tightly together with masking tape while the glue dries, just the same process really as joining the back or top. When the internal lamination (at 90 deg.) has the two outer laminations glued to it, there are most unlikely to be any issues attributable to a butt join.

[Mike Thomas]

Side Veneers.JPG (191.34 KiB) Viewed 14180 times

The picture shows the Blackwood veneer I used for my Selmer. The third from the left is the internal lamination, made up of butt joined veneer .7mm thick

[auscab]

There is no problem joining the pieces of the internal lamination with a butt join. Glue the pieces together with whatever glue you normally use, Titebond, LMI glue etc., hold them tightly together with masking tape while the glue dries, just the same process really as joining the back or top. When the internal lamination (at 90 deg.) has the two outer laminations glued to it, there are most unlikely to be any issues attributable to a butt join.

Thanks Mike,
Just a straight out but join , ok , I'm over complicating it .
Nice picture of your vacuum set up.

I'm interested to know if you measured the finished thickness.
When you glued up 4 x .6mm veneers + glue did the lamination end up being dead on 2.4mm ?

[Mike Thomas]

Rob, with 4 nominally .6 mm veneers, glued in a vacuum press using West Systems epoxy, the finished thickness varied between 2.35 and 2.45 mm. So, they were still very close to 2.4 mm. Some of the veneer may have been a little under .6mm in places, and there may have been a little compressing of the veneer in the vacuum press, but it is clear that the glue film didn't add anything significant to the thickness. Incidentally, there was quite a lot of bleed through of the epoxy to the outer surfaces, through the pores. This was quite easy to scrape off after curing, however, without removing wood, thus achieving a fairly respectable pore fill in the process.

[nnickusa]

Hey Rob,
Finally remembered to chack the plan. What it says is 1mm rosewood over 1.5mm cypress. Solid back.

[auscab]

Interesting Nick , Thanks.
I did see that Martins from the 1830s to the 60s had BRW veneer on spruce for backs. Here is a picture of the inside of one at frets.com

http://www.frets.com/FretsPages/Blogs/1 ... 126_1.html