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greenscoe
11-03-2017, 04:03 AM
I’m a hobby maker and have been inactive this year. Recent talk of experimenting on the forum has inspired me to venture into the workshop to try one of my own. I decided to investigate a new bracing pattern.

To save time and effort I used a 30 Chinese laminate tenor as a donor instrument.

It occurred to me that those new to making could adopt this approach. By making a new top for a used/cheap instrument they ought to get a feel for building and hopefully improve their donor instrument.

I cut the fretboard at the 14th fret and hacked out the top, then cleaned up the existing lining before stiffening it with strip material (photo is before stiffening added).

My new top is of Engelmann spruce (approx. 1.7mm thick) using initially 5x5mm Engelmann spruce bracing. I’ll let the 2 photos tell the story: suffice it to say I am aware of many alternatives to standard fan bracing and this form was influenced/inspired by an image of bracing by Tom Rodriguez.

It’s necessary to protect the back with card during this work. I should add that care should be taken to ensure the neck doesn’t lose vertical alignment when gluing on a new top.

The instrument is now punchy. It’s very responsive across the range, has lots of sustain and volume. It sounds very different from my other instruments and not what I expected: I'm quite happy playing this. It’s therefore a successful experiment. I would now like to try a similar bracing pattern on one of my ukes in the future.

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ukantor
11-03-2017, 05:42 PM
That's a very useful ruse. Glad it worked out well!

Vespa Bob
11-03-2017, 06:15 PM
Good work, glad that it turned out better than expectations! As it happens, I am involved with something similar, in that I am experimenting with my first ukulele, a cheapo bought many year's ago. I also replaced the top with spruce, but stayed with the original's bracing pattern. Your advice about taking care that the neck stays in vertical alignment came a little late, as I neglected to do this and ended up with a neck so negatively out of alignment that I had to add a wedge shim to the neck to bring it back to zero angle! Not fun. I'm waiting for the rain to clear before the final finishing of this experiment. I hope mine turns out as well as yours!

Bob

sequoia
11-03-2017, 06:59 PM
ended up with a neck so negatively out of alignment that I had to add a wedge shim to the neck to bring it back to zero angle! Not fun. Bob

Been there done that. Not fun is an understatement. Are we having fun yet? Not really unless you like hitting yourself on the head with a hammer. Nightmare stuff... (shudders). It can be done sure, but hiding things is darn near impossible.

Vespa Bob
11-03-2017, 07:03 PM
It can be done sure, but hiding things is darn near impossible.

You'll see how I accomplished this when I finally get to finish the project!

Bob

greenscoe
11-05-2017, 02:59 AM
If you read about Tom Rodriguez ukes and his approach to bracing you'll appreciate why I tried this form of bracing:

https://rodriguezukuleles.wordpress.com/