Brace and bridge placement (AKA halp me with my blueprints).

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n~dl
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Brace and bridge placement (AKA halp me with my blueprints).

Post by n~dl » Sat Jun 29, 2013 11:14 am

Sorry if this has been talked about, digging through both the books and the forum and didn't come across anything.

Attached is a pic of a blueprint I'm hammering out for a falcate steel string. Just wondering about the positioning of the secondary falcates in relation to the particular bridge I've designed. You can see they sit right about where the wings begin to taper. Should they maybe be closer to the center? The wings are going to taper down relatively thin (1/8"?), so I don't imagine they are doing much to torque the top; to my thinking the braces would better disperse the load from more directly underneath the biggest, stiffest portion of the bridge rather than out there on the wings. On the other hand--the primary braces are already there doing exactly that, so maybe it just isn't necessary to go crowding the secondary braces in there.

Any thoughts at all?
Attachments
bridge and braces.jpg
-Nate L

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n~dl
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Re: Brace and bridge placement (AKA halp me with my blueprin

Post by n~dl » Sat Jun 29, 2013 11:36 am

(I think I already have the secondary braces about 5mm closer to the center-line than where the plans place them).
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n~dl
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Re: Brace and bridge placement (AKA halp me with my blueprin

Post by n~dl » Sat Jun 29, 2013 11:39 am

ALSO: Anyone have thoughts on cutting away the bridge plate as an alternative to rebating the braces?
-Nate L

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Trevor Gore
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Re: Brace and bridge placement (AKA halp me with my blueprin

Post by Trevor Gore » Sat Jun 29, 2013 12:10 pm

The secondaries are fine with respect to the bridge. Wings at 3.2mm are fairly thick, and you're not very far from the full thickness part, anyway. I've gone much thinner on occasions. If I were doing it, I'd have the ends of the secondaries dividing the lower bout more evenly, i.e. more bend in the secondaries to close the gap a little more between the secondaries and tertiaries. Don't forget the little brace in the middle of the lower bout, below the bridge.

I'd definitely rebate the braces rather than split the bridge plate. You can take the bridge plate down to 1.5mm thick, if you wish though, but use the CF.

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n~dl
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Re: Brace and bridge placement (AKA halp me with my blueprin

Post by n~dl » Sat Jun 29, 2013 12:32 pm

Thanks! Yeah, I was looking at it more and they're right where the bridge begins to ramp down to the wings, not floating way out on top of them, so I think you're right. I didn't notice I placed the ends of the secondaries so close to the primaries, I'll change that.
The lower tertiary will make it on the blueprint eventually. :mrgreen: Along with plenty of other things like a tail block, maybe even a cutaway I don't think is ugly!
-Nate L

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Tod Gilding
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Re: Brace and bridge placement (AKA halp me with my blueprin

Post by Tod Gilding » Wed Jul 03, 2013 2:22 pm

Just curious Nate, what is the CAD program that are using there ?
Tod



Music is everyone's posession. It's only publishers who think that people own it.
John Lennon


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n~dl
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Re: Brace and bridge placement (AKA halp me with my blueprin

Post by n~dl » Sat Jul 13, 2013 9:52 am

Yep, Rhino v. 5. Thank goodness for their generous student discount!
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Tod Gilding
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Re: Brace and bridge placement (AKA halp me with my blueprin

Post by Tod Gilding » Sat Jul 13, 2013 11:22 am

Thank You Trevor and Nate :)
Tod



Music is everyone's posession. It's only publishers who think that people own it.
John Lennon

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