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Hi everybody!

Im new here, I am from Serbia Europe, my English is a bit russty and Im starting to make acoustic and classic guitars. I want to try someday to make double top for guitars because of the much better sound and responce, and I watched many of videos of making guitars, and also how to make double tops...

I get it how to do it its not nuclear phisics , but material its imposible to find here in Serbia, i mean for Nomex, and good epoxies.

Do anybody know where I can buy that material in Europe, or to tell me where to search, who sell this?

I need Nomex 1.5 mm thick... with 1/4 inch cells.

Cheers..

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Guitars are simply beautiful.

Hello Jovan, and welcome. You're right, there's nothing high-tech about Nomex double tops. We're talking 1960's technology. Luthiers Mercantile International sells the Nomex. There is probably an aerospace contractor closer to you that could give you a better price. Nomex, Kevlar, any aramid fiber will work for guitars.

You don't need epoxy. Many builders use polyurethane ("Gorilla Glue" here).

On the other hand, not everyone loves the "double-top" sound. Loud? You bet! Beautiful? It gets complicated. Guitars are complicated.

In Europe you may get Nomex from Madinter, Spain, or the german company R&G, who also makes quality epoxies.

Hello again!

Wow finally right answers, In Serbian forums when you ask about something unusual they look at you like you are alien

Thank you all for replies, you'r all very kind.

One thing you must have know, that in Serbia is diferent for many things. Life standard is much lower, and most real values you can't charge as should. Here is hard to find good qualitty spruce and wood in any way, and it's very expensive to buy everything from STEWMAC, some things you have to, but much of tools I tried to make by myself.

You can find here solid quallity spruce, there is lot of conifer woods in Serbia, and usualy you can find it on construction materials storage, of course must search and search and search to find dry and right cute wood, to find masterpeace is much complicated. My friend(also guitar maker) find good board of spruce in that kind of storages, and guitars made from that sound fine. My point is to make lower quallity spruce sounding better.

Im starting to make my first guitar, I have one set my friend cut for me, its wallnut 26 years old and set of spruce, and some mapple for neck.
For this first guitar I will use some "sad" mapple boards I find on construction storage and set of spruce, that wallnut will leave for second guitar Im planing make for my girlfriend birthday, I hope I make it both till march
I had idea to make double top guitar for my girlfriend, but I little overestimated myself
In some future, hope so I will make some double top guitar, and I keep searching for right materials till then. I'll post some pictures of buiding of course

Filippo Morelli is that guitar on your avatar is your work?? MAN looks like MASTERMASTERPEACE :O

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Guitars are simply beautiful.

Hi Jovan,

you can get nomex from Madinter in Spain: http://www.madinter.com/nomexr-560x410x1-5mm.html
Barber sells Titebond PU: http://tonewood.es/index.php?id_product ... &id_lang=1 , but i guess you should be able to find it locally easily.

You might try this German dealer for epoxy, see if it sells to Serbia: http://www.maritimusboote.de/WEST-SYSTE ... paraturset

good luck!
miguel.

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member of the guild of professional dilettantes

Hi Jovan,
If the reason you are going with a double top design is to use lower quality wood, I would suggest you consider making a multi-piece top instead. Some of the finest guitar makers (Torres) have built guitars using 4 or more pieces for the top. This allowed them to select narrow sections of boards that had the best qualities for soundboard material.
What glues are available where you are?


Has no one ever used hide glue for double top construction?

Hide glue doesn't have a long enough open time.

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Old growth, shmold growth!

I've only made one double top guitar and it sounds ok but not spectacular. But it was the only one I have ever built as an experiment. I will try again to build another one in the future and change things up a bit. Just a couple of points, you can save your best looking wood for the top and hide the less quality wood on the inside of the guitar. Also I really can't imagine building a double top guitar without a drum sander. This could be due to lack of builder skills but you have to get the plates so thin and even across the whole top that it would be very difficult to hand plane, scrape and sand.

Hi again and again

I heard about this multi piece tops, but i don't really understand how that pieces are glued together? It's like plywood like layers? This metod doesn't sound logical to me, because layer of glue between layers kill sound and vibration, but I guess it's not that metod of glue-ing

Can you give me some explanation or some link, video?

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Guitars are simply beautiful.

I can buy titebond here, probably best glue I can find in Serbia, there is also few of epoxies

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Guitars are simply beautiful.

Instead of jointing two book matched pieces, you joint 3 or 4 pieces lengthwise, not on top of each other.

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member of the guild of professional dilettantes

They're glued side by side, edge joined to one another. Guitar tops are two pieces joined side by side, same thing here, just 4 pieces so you can work with narrow boards.
Hope that helps,

edit: Miguel posted while I was typing, sorry for the double (sort of) post

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Jim Watts
http://jameswattsguitars.com

I don't think that Titebond will work well for the double top construction. Like some have mentioned polyurethane glues like Gorilla Glue will work but I don't like them because they foam up. You don't want the Nomex cells to get foam in them, the trick is to use just the right amount of glue so it doesn't foam but with epoxy you don't have that problem.

Yes I know all that man, you ask about glues what I can find here, and I mentoned Titebond just to know that of some things I CAN buy here

I watched many videos on youtube from Robert 'O Brien, one of this video is when he visit one Luthier who making only double tops on all his guitars. He explained metod of glue-ing and how inflict glue on every surface. He uses 2 component epoxy glue named "T88" which I don't have to buy in Serbia offcourse
http://www.youtube.com/watch?v=uIq-ExdmG5I

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Guitars are simply beautiful.

Is that metod better for sound just because of 4 pieces(better vibration maybe), or just that way can give you better hardness of wood with thicker lines?

I guess that you can choose peace of wood with thicker lines, cut it and merge together with another 3 you choose?

What is effect of doing that in first place?

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Guitars are simply beautiful.

I think the advantage of using 3 or 4 pieces is simply this: if you don't have two pieces wide enough to make a top (or back.) What I am saying is if your only good wood is not wide enough to make a top out of 2 pieces, you can use more pieces to get the width you need. Hope that makes sense.

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Phil

http://www.oleninstruments.com

"Those who tilt at windmills are only considered insane by those who can't see the dragon."

Hiya Jovan,
Honeyboard sandwich material -> http://shop1.r-g.de/cat/Sandwich-Werkstoffe
Think it's cheaper than madinter as 1/4 board = 610 x 1120 mm for 36,65 € vat incl.
I don't use nomex but I do use their epoxy (HT resin)
They also have glasfiber rods which can be usefull for a gobar deck and if you're interested in carbon fiber rods for neck reinforcement you are at the right place.
Think they ship to Serbia and normally their shipping cost is not stupidly expensive.

O'brien video regarding double tops -> http://youtu.be/uIq-ExdmG5I

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Hilko, that´s rather helpful. Thanks!

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member of the guild of professional dilettantes

Boheeem,

Gook luck with doing a double top as your first build. It sounds like doing even a traditional single top in Serbia would have its share of challenges. Stay encouraged even with difficulties.

Ed

thanks man I will check it

I watched this video many many times, and I will watch it again

I must create paypal acount, after that I will able to buy some necessary things from stewemac and other...

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Guitars are simply beautiful.

Thaks man, but first guitar I will not make it with double top, because I have already cut one spruce set, and still don't have material I need. This guitar is gona be experimental for first one and I make it with poor wood to practice

Second one shall be better I hope so, because Im planing to be birthday gift for my girlfriend

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Guitars are simply beautiful.

Does it really matter if the glue foams up? The mass is there anyway - does it matter how it is distributed in the gap between the outside skins?

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Jim Kirby
kirby@udel.edu

Good point and now that you put it that way I don't know? I guess I was thinking that if it foams up filling the cells it would ruin the airiness of it.

No experience with this, but I would guess it does. If the glue is in a hard solid film, it will transmit sound much better than a soft spongy mass. It's like making a guitar top out of polystyrene...

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"I am always doing that which I cannot do, in order that I may learn how to do it."
Pablo Picasso

https://www.facebook.com/FenskeGuitars

I had a discussion recently with a local builder, David Pace in Baltimore, who builds classical guitars, about 1/2 double tops and 1/2 conventional solid tops. David said that his double top plates come out a little bit heavier than a solid wood top, and that he didn't think that weight was the key to what makes double tops different. He thought that the difference was the more isotropic nature of the top stiffness, with much less variation between along-top and across-top in the unbraced plate when the double top is used.

(Well, that had nothing to do with whether the nomex core should or shouldn't get filled with foam )

Damann's original tops simply had wooden spacer strips, which is probably not a great idea as the outer skins aren't uniformly supported as well as with the nomex core, but if isotropic-ness is the key, you could probably do an initial version that would simply be like laying up plywood - just use a middle layer of spruce or cedar or something with grain running side to side, and that plus the two glue lines should even things out pretty well. You could use balsa for the middle layer too.

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Jim Kirby
kirby@udel.edu