3 ply vs 5ply laminates

**jazzimprov** · 05-22-2022, 01:54 PM

Laminates:

Manzer and Sadowsky -5 ply

Others at 3 ply.

Is it cost saving?
(Seems reasonable to bring the cost down if so)
Sound difference?

Thx

**Gitterbug** · 05-22-2022, 02:43 PM

A good question! I didn't know that a) 5-ply is in instrument use at all, and that b) Linda Manzer, probably the most expensive luthier of our time, is using some. The standard veneer thickness in plywood is 1.4 mm. Ordinary 4 mm plywood is 3-ply, with nominal thickness achieved after sanding. Next up is 6.5 mm, 5-ply. The thinnest birch veneers I know of are 0.15 mm, used in aircraft plywood. The more layers, the more glue between them, and the more specific weight and rigidity. In my experience, a good 3-ply top archtop beats a bad carved top. 5-ply to me is too rigid to shine acoustically. But I'm happy to stand corrected.

If I were to build archtops, I'd experiment with a 3-ply pressed top, with the bottom layers like 10 degrees offset. This would be enough to eliminate cracks, yet produce a more vibrant top than with a middle ply straight across. Of course, no match to a hand carved top with a recurve and all, but who needs those in our electrified world?

**JohanAbrandt** · 05-22-2022, 03:25 PM

Manzer makes the laminate herself, claim is that its the same (way) as made for Daquisto

16″ Archtops – Manzer Guitars

**jazzimprov** · 05-22-2022, 04:10 PM

Just noticed that Sadowsky and Manzer is 5 and Holst is 3.
He does the laminates himself as well from what I understand.
No doubt Holst does beautiful work while trying to make his guitars accessible to more musicians with his pricing
Even his all wood archtops are far less than others while maintaining the highest quality of workmanship.

Wondering if there is any discernible difference.

**Grez** · 05-24-2022, 10:40 AM

5 ply here at Grez for everything except spruce. 1/42" thick veneers, that's .024" or 0.6mm so the final thickness is about 3mm or .118". In practice more like .120".

A few random thoughts:

The weight of the glue after it's cured matters a little more with 5 ply vs 3.

5 ply allows for much variation in the orientation of the layup. Much like carbon fiber in cars/airplanes/bicycles, you have some control over stiffness (where it is and isn't) by altering the layer orientations.

5 ply allows for more mixing of species to control stiffness since you can't control stiffness with thickness as you would when carving.

I'm by no means saying 5 is better or worse than 3. As with most things, just different.

Barry

**John A.** · 05-24-2022, 10:55 AM

Originally Posted by Grez

5 ply here at Grez for everything except spruce. 1/42" thick veneers, that's .024" or 0.6mm so the final thickness is about 3mm or .118". In practice more like .120".

A few random thoughts:

The weight of the glue after it's cured matters a little more with 5 ply vs 3.

5 ply allows for much variation in the orientation of the layup. Much like carbon fiber in cars/airplanes/bicycles, you have some control over stiffness (where it is and isn't) by altering the layer orientations.

5 ply allows for more mixing of species to control stiffness since you can't control stiffness with thickness as you would when carving.

I'm by no means saying 5 is better or worse than 3. As with most things, just different.

Barry

Thanks for that explanation. When you say "everything but spruce" are you talking about spruce laminates? If so, I'm curious -- why would you use a different number of plies of spruce from what you use with other species (I happen to have wound up with three laminated-spruce-top guitars via my random guitar acquisition process).

**Grez** · 05-24-2022, 11:24 AM

John, For Spruce, I have a billet custom milled into veneers about .055" thick. Then do 3 layers with the grain all oriented the same way. With this thickness I can graduate the top a little via aggressive sanding on the top and back. The end result is something that sounds like a spruce archtop but is a little more feedback resistant with of course the trade off of being a little less loud acoustically. The intent is a spruce top electric archtop, not a spruce top acoustic archtop with a pickup. Slightly different customer.