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The subject line says it all, really.
I want to try building a Contreras(Sr)-style classical and I'm trying to find as many construction details as possible.
I've got a copy of the 'Earl Raymond Wells' plan of a 2005 Model 1A by Manuel Contreras II and the bracing plan from Allied is on the way.

I also found some details of a Todd Lunneborg Contreras-style guitar at
http://www.luthiercom.org/phpBB3/viewtopic.php?f=72&t=1084&st=0&sk=t&sd=a&sid=5a9248880c78137bd349f7e6a1437e2d&start=25

I'd appreciate any details, pictures, links or suggestions for sources of information for this project.

Thanks!

John

The first page of Todd's discussion is at
http://www.luthiercom.org/phpBB3/viewtopic.php?f=72&t=1084&st=0&sk=t&sd=a
Scroll down for pictures of the 'double back/double top'.

Hi John
I made a similar enquiry a few weeks ago and as well as Todd I found http://www.anzlf.com/viewtopic.php?t=1553 on the ANZLF with an beautiful Selmer type build. and Todd did respond, saying his didn't work, he was going to cut soundports in the back.
Zip on a classical from any direction, apart from the odd photo.
I hope you have more luck.
Colin

_________________
The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I am curious if your plans show the extra top in the back as suspended. I have heard from more than one source that the original double tops were cedar backs with a thin veneer of hard wood.

Thanks for the replies.

The plan I have does not show a 'double back' at all- it's a Manuel Contreras II 1A Especial (Rio) model.
I have also read about 'double backs' with an inner laminate of cedar or spruce (to match the soundboard?).
Inner laminations (back and/or sides) of cypress are also not extremely unusual, I think.
Some details:
Cedar top with 5 fans, the outer 2 fan braces curved.
Braz RW b+s
Aside from the curved fan braces, the other unusual feature shown on the plan is an additional 7x8 mm (mahogany) brace about midway between the bridge and soundhole. This brace is 'suspended' about 25 mm below the soundboard, attached only at the ends by spruce 'pillars' glued to the sides. A 8x20x21 mm cedar block glued to the mahogany brace contacts the central fan brace, 'supporting' it.
I think the idea was to provide some additional structural strength so that the 'harmonic bar' (aka LTB?) could be scalloped.

Another detail is that the bridge reinforcement patch is cut away under the saddle area, and centered on the tie block, so that it extends toward the heel further than the bridge.

Whether any of these ideas actually improve the sound of the guitar is another issue entirely. It is refreshing to open a plan and see some 'different' stuff going on, though....

Cheers
John

I too am interested in this doble Tapa concept....
John A...slight thread inter weave I will try and get some photos of the Contreras I looked at
but a couple basic things apart from the curved fan braces which i never saw before.
Long scale 665mm....Deep body 4" 3/16th tapering down to 4"
14.5" UB 11.0"Lb 19.5"long so big box
Massive back radius in both directions way more than 15' didnt measure it yet
No double anything but very loud with chorusy trebles kinda strange actually
aside from the links above not much info on the double back
Mangore.com sells them but i cant figure out the photos..it looks like a partial second back Ie it has a large hole in it rather than the whole spruce false bottom I think its like the one at the bottom of this page
http://www.guitarrasramirez.com/english ... nalEn.html
I also saw one somehwere that looked like it sat on legs a bit like one of The Padmas Virzi plates but upside down..
if that makes any sense....would be nice to get to the bottom of this little mystery!

http://www.keldayguitars.com/keldayguit ... _back.html

dont know what to make of this

Thanks, Steve-
Interesting stuff.
The Kelday looks like a laminated back (unbraced?) glued in a vacuum bag?
The sides are definitely laminated with vacuum bag over the bending form.

Cheers
John

It definitely looks unbraced probably laminated but are there not two RW plates about 11/2" apart on the back

Don't know how much this will apply, but while looking for info on Vicente Arias I came across this blog from an Arias guitar owner. He shows some photos of his Arias guitar from 1899, and has a double back. You can see that the inner back is suspended just inside of the outer back, but not enough photos to really see how it is working on the other side.

http://oldromanticguitars.blogspot.com/

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Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

Doug-
Thanks for that link- interesting stuff!
(I'd like to have 'flea markets' with Arias guitars around here.....)

Cheers
John

John, you are welcome. I would love to have that kind of flea market here, too!

I used that particular bracing on my recent double cutaway guitar. I had my doubts, but it works very well! I used it on a large plantilla and used WRC. I would like to try it using Spruce on a smaller plantilla, to compare to my FE17ish guitar.

BTW, I am VERY impressed with the results of the FE17ish guitar. It is the best sounding that I have done to date, and I've said that a lot on recent guitars. Not bad for a guitar on which I spent the equivalent of $32! Getting some recording done next week, yeah!

If your Contreras double tapa investigation turns up nothing, I'd encourage you to try an FE17ish guitar like I did.

_________________
Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

I'll put it on 'the list' ! I guess I'd better 'save' your build record from MIMF before it's deleted over there- I'll need it!
Do you think the tornavoz 'adds enough' to make up for the lack of future access through the soundhole for adjustments and repairs? (Silly question, really- I guess it's hard to tell without the same guitar sans tornavoz for comparison.)

I've just started a Rodriguez-style guitar. I want to try a 'large-body' guitar to see if it is more in line with the sound I'd like. I really do prefer small, light guitars for appearance and playing, though.

The Contreras inquiry is turning up some interesting side-leads, but no real direction for a DobleTapa build, so far.
I'm still curious, though....
Cheers
John

This guy is building what he calls "double body" guitars
http://www.shelton-farretta.org/guitars.html

John,

I can't tell just how much of the sound is due to the tornavoz, but I expect that it is responsible for something! The bass is deep and profound, the mid range full, and the treble clear and singing. There is a quality of big space that is very difficult to describe. I have noticed the one time that I have been able to listen to someone else play that the projection is excellent, quite a different sound from what I get behind it.

_________________
Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

I recommand SE114 if you don't want to mess with a tornavoz. Better yet, you can apply a double-layer laminated back to this design and get good result. My recent work is a SE114ish guitar and it has a 3mm-thick back laminated with a solid Amazon RW and a WRC plate. I was told that this kind of back lamination was used long before Contreras Sr. was born and they did this for the sound, not because it's cheaper(It's not!).

By the way, the local dealer of Contreras guitar I've mentioned, who is also a great player, has switched to a Hauser III about five years ago.