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Brace for this one
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Author:  Michael [ Sun Jan 04, 2015 8:09 am ]
Post subject:  Brace for this one

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I still need to sand down the lumps on this one then install braces. It is a Style 0 like this...
http://inlowguitars.com/archtop-acousti ... tist-1921/

This is not an exact copy. The original guitar was braced by two pillars extending from neck to tail on either side of the guitar. I thought a "modern" X brace might be a better choice. I apologize for the poor quality of the photos. The sound hole will be a 3" X 4" oval. The lower legs of the X must fall 3" apart under the feet of the bridge.

Idea number one...

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Idea number two...

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Side by side...

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So... thoughts??

Michael

Author:  Clay S. [ Sun Jan 04, 2015 9:00 am ]
Post subject:  Re: Brace for this one

To me, both of those designs put the "X" intersection too far down. You could do bent "bow legged" braces to get the intersection closer to the sound hole and still have the 3" spacing for the bridge. Kind of a "Falcate X"

Author:  Clay S. [ Sun Jan 04, 2015 9:00 am ]
Post subject:  Re: Brace for this one

To me, both of those designs put the "X" intersection too far down. You could do bent "bow legged" braces to get the intersection closer to the sound hole and still have the 3" spacing for the bridge. Kind of a "Falcate X"

Author:  Greg B [ Sun Jan 04, 2015 11:51 am ]
Post subject:  Re: Brace for this one

The feet of the bridge are only 3" apart? It looks more like 4" in pictures.

Anyhow, probably they will both work, but sound slightly different. How's that for useful insight? :) If going with option 1, IMO the upper arms of the X should be extended all the way to the lining. They could easily come loose where they butt the cross brace. Still, I would lean toward option 1. I assume you are using a trapeze bridge. You don't need that much bracing, just enough to keep the arch from collapsing. Perhaps the mandolin/mandola crowd has something to say?

EDIT: On second thought, the second option (minus the big 'fingers') is more authentically early Gibson, and should provide a little better structural support since it goes into the upper bout.

Author:  cphanna [ Sun Jan 04, 2015 3:28 pm ]
Post subject:  Re: Brace for this one

Hi, Michael,

How about something like this? (I took the liberty of putting a quick digital drawing over your photo.)

I don't know much about style 0s in particular, but that's a cool instrument you've got in the works. You have a very deep arch which ought to be as strong as all get-out. I can't tell whether it's more or less flat along the top at the center line and I don't know if it's appropriate to scrape recurve into the edges of a 0, as with a more modern arch top. It appears that the original has a bit of recurve. With all that in mind, I would personally NOT extend the braces to the perimeter. I'd taper them down and feather them off 1.5 - 2" from the lining in the lower bouts. But do some more research on that particular, because I'm thinking "Benedetto arch top" when I say feather the braces. That approach might not be the right one in this case. Remember, too, that there's no rule that says your braces have to be configured symmetrically. Cut a couple of 1/4" wide strips of paper and push them around on your plan until you get a layout that you like.

Please let us know how this comes out. I think it's a very exciting project. I'm lovin' it!

Author:  Michael [ Sun Jan 04, 2015 8:01 pm ]
Post subject:  Re: Brace for this one

CP.. I discovered that my drawing labeled "Idea number two" has the bridge placed 1" lower than where it should be. I like your brace choice and that is what I will go with. Thanks for helping me discover my error.

Michael

Author:  cphanna [ Sun Jan 04, 2015 8:49 pm ]
Post subject:  Re: Brace for this one

Well, Michael, Anyone can have an "oops". It means nothing but a chuckle if it is discovered in the plan drawing. I am not so sure I helped you all that much, but if I assisted a little bit, then I'm glad. The main thing, of course, is that it all works out for you in the end. I am pretty confident that it will.

I think if you could post a profile picture of your top, so that the arch top experts out here could see your arch and the degree and length of flatness over the center line, it would help those folks chime in with some really useful advice for you. For example: People might be able to advise you on brace height and length of taper and so many other variables, if they could see your top curve in a profile view. I think there are quite a few people out here who are rooting for you, even if they haven't chimed in yet.

I'm no arch top expert by any means, but I sure am an arch top enthusiast. I think you're doing an extremely cool guitar there and I want it to be a killer outcome for you. I know you do, too. (Well, OF COURSE you do!) So...keep posting pictures and expert help will follow real soon!

Nothing does it for me like a nice arch top!

Patrick

Author:  Dave Livermore [ Sun Jan 04, 2015 11:50 pm ]
Post subject:  Re: Brace for this one

Suggestion on fitting the X once you decide where it goes...
Laminate strips of thinner quartered material. Thin laminates will conform to the arches.
Build up the lams until you reach a desired height.

You can even overlap the X instead of cutting a lap joint.

It will be incredibly strong, and you can still carve and tune it as desired.

It was the first thing I thought of when I saw the picture, before I read the post and I thouht I would share it with you.

dl

Author:  cphanna [ Mon Jan 05, 2015 10:31 am ]
Post subject:  Re: Brace for this one

Dave, that's a very interesting idea. I've never seen it suggested anywhere, but it seems very logical. In an arch top with twisting curves, do you find it difficult to stack the laminations? Seems like the lams would naturally keep following the inside curvature and result in twisted braces. How do you handle that?

Author:  Dave Livermore [ Mon Jan 05, 2015 2:25 pm ]
Post subject:  Re: Brace for this one

Even if the laminated brace is twisted, you can still carve it straight.
That is a perk of the technique

Author:  Dave Livermore [ Mon Jan 05, 2015 2:51 pm ]
Post subject:  Re: Brace for this one

Here are a couple shots of a back I used this on a while ago. Don't use the method any more because of how CRAZY much is stiffened the back. I tune my top and back plates together (before the bridge is glued on) and couldn't get them even close with this. Very strong. Very effective.
Knowing what I now know, I should experiment with this again and see what happens.


First layer of laminates.
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Third layer
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Finished and shaped
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Author:  Michael [ Sat Jan 17, 2015 8:30 am ]
Post subject:  Re: Brace for this one

The top is braced and sound hole bound. I will inlay a rosette today.

Image

Michael

Author:  Michael [ Mon Mar 02, 2015 7:07 am ]
Post subject:  Re: Brace for this one

This one is coming along nicely.This is a very difficult build. Still have a lot of trimming and sanding to do.

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I wanted to share the progress with my friends on the OLF. For full documentation go here..

http://www.luthierforum.com/index.php?/ ... r-guitars/

Michael

Author:  Hesh [ Mon Mar 02, 2015 7:35 am ]
Post subject:  Re: Brace for this one

Looking pretty cool! Nice work Michael!

Author:  cphanna [ Mon Mar 02, 2015 10:34 am ]
Post subject:  Re: Brace for this one

Looks beautiful, Michael. That rosette is gorgeous.

Author:  Chris Pile [ Mon Mar 02, 2015 10:36 am ]
Post subject:  Re: Brace for this one

ME LIKEY!

Author:  dzsmith [ Mon Mar 02, 2015 12:16 pm ]
Post subject:  Re: Brace for this one

Dang! Nice work Michael!

Author:  SteveSmith [ Mon Mar 02, 2015 12:51 pm ]
Post subject:  Re: Brace for this one

That is very cool. I like it a lot.

Author:  Greg B [ Mon Mar 02, 2015 2:13 pm ]
Post subject:  Re: Brace for this one

Looking great so far. Are you going to do some vintage style stained and/or dark burst finish?

I always thought the style 0 was one of the prettiest guitars ever. OTOH, the sound of the ones I've heard leaves something to be desired. A hotrodded style 0 that sounds great and looks great would be the holy grail.

Author:  Barry Daniels [ Mon Mar 02, 2015 4:45 pm ]
Post subject:  Re: Brace for this one

Looks really nice. Did you try to steam out that dent next to the top binding?

Author:  Michael [ Mon Mar 02, 2015 10:26 pm ]
Post subject:  Re: Brace for this one

Yes, Greg, It will have a tobacco sunburst.

Barry, I did not see that tool mark until after I took the picture. I am still in the first stages of sanding/shaping with 80 grit and the area has since been smoothed out. I did not steam it out but I have used that method in the past and it actually works very well if it is a compression (dent). This was not a dent.

Image

Michael

Author:  Michael [ Thu May 28, 2015 7:58 pm ]
Post subject:  Re: Brace for this one

Progress...

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Getting close now

Thanks for viewing

Michael

Author:  Jim Watts [ Thu May 28, 2015 8:24 pm ]
Post subject:  Re: Brace for this one

That's coming along nicely.

Author:  SteveSmith [ Thu May 28, 2015 9:10 pm ]
Post subject:  Re: Brace for this one

Very nice indeed. Interesting and unique.

Author:  Chris Pile [ Thu May 28, 2015 11:16 pm ]
Post subject:  Re: Brace for this one

When you're done with that, then make another - and string it up as a mandocello!

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