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2012-07-15

Gluing the bracing

After I excitedly prepared the brace blank what's next?
Naturally it's to glue them in.
Before that I prepared the donut (sound hole reinforcement).

I had a dry run 1st before doing the actual gluing and keep all the things I need at hand.
Luckily I did the dry run as I realised I had adjusted the upper deck of the go-bar deck upwards to cater for the gluing of the back aka closing box.
So I had to adjust it down. After that I recall that I had to work inside out.
The dry run was done and I began to start.

The HHG was at hand I did everything in about 15 minutes.
That was pretty fast.

Shooting and jointing the donut.


Cutting out the donut. The inner circle is same as sounhole. Some maker cut the soundhole after the donut is glued. I prefer to do them separately for better alignment


Shooting the sides to cater for the LTB and UTB.

Rough bracing layout

Dry run


Apply hide glue to the donut.


Donut glued and preparing for 1st brace. The metal rule is a guide to prevent the bracing from skidding and slipping away.


Center brace glued.


Ensure it conforms to the doming


Working from center out to the outside


All glued


After the gluing dried, I began to carve the brace.
I use the thumb plane and chisel.
I reduce the height of the brace to 3mm as per Torres.
And then trim the length-wise profile to a gradual sloping profile towards the ends.



After the go-bars are removed.


Reducing the height of the brace to 3mm


Checking the height of the brace


The length profile of the braces.


Another view under light to better see the bracing profile

After the fan braces were done, I began to work on the traverse braces.
First of all is fitting the large Bouchet brace over the fan braces.
I fit the bottom of the Bouchet brace by marking the pencil over the solera.
Then I shoot the bottom of the brace according to the line drawn.
After that I mark the fan brace position and measure the height of the braces and chisel the notches in the Bouchet brace.
I had to adjust some of the notches to fit.
Finally all was set but at the bass end the base of the brace didn't fit as well.
I had to shoot further to adjust until they fits.
I use the go-bars to clamp and check the fitting.



Trace the solera doming curve onto the Bouchet brace


After shooting to fit


Measure the height of the brace


Mark on the brace


Saw the notches


Chisel the notches


Check fitting


Fitting over the go-bar


Another view


Close up view


It's time to glue up the braces.
This round I glued up the closing brace, Bouchet brace, and 2 side braces (UB)
The procedure are about the same except I need not use the ruler.
The existing brace will prevent too much skidding around of the brace.

Preparing to glue.


Applying glue to the closing brace.


Clamp using go-bar


2 side braces glued and clamped


Applying glue to the Bouchet brace


Clamped down with lots of go-bar


After the glue dried I began to carve the braces.
For the side brace, I make the brace 1mm taller, the bass side is 3mm, treble side is 4mm.
The closing brace is 3mm tall as per Torres.
The bouchet bar is the one that I have no experience with...
So far after I shape it with the treble side taller, I tapped the board and it felt overly stiff.
Think I will have to thin them more.
Meanwhile I probably do tap tone recording and analyse how to thin them.

After taking off the go-bars.


Close up look


Thinning the side brace


Thinning the Bouchet brace


After shaping the Bouchet brace - I probably thin them further.


Shape the donut


Check the weight so far: 180.7g


Full brace with UTB LTB and treble bar, let check the weight again.


Oops... overweight. Time for some diet; target weight is under 200g preferably under 190g region


Saw slots in the UTB for making the opening aperture


Chisel away those slots and then file them smooth


Full bracing pic.


I am quite lucky to have a mentor to guide me whenever I have doubts.
I asked Alexandru Marian who is an expert in making Torres and Bouchet style guitars on what are the dimensions of the Bouchet brace.
He commented my brace is too big and too long.
And so I reduce the height and length of the Bouchet brace.
Now it looks much nicer.
The weight is 202g almost there!
If you ever look for a Bouchet style or Torres style guitar, look for Alex, you won't be disappointed in the guitar.
And good thing now is his guitars are undervalued now == value for money.
When I save enough I will order one from him too :)



Carving the Bouchet brace


Almost done probably will refine more.


With the UTB and LTB


The weight 202g


Next I glued on the traverse braces.
Nothing new but using the same solera and go-bar deck.


Last check before gluing


Gluing the LTB


Gluing the UTB

The bracing is done, after cutting off the excess ends of the traverse braces, the final weight was reduced to 197g.
Not much but at least it's less than 200g.
I would have prefered it to be in the 180s region though.
Here are some pics of the final bracing.



The final weight of the top.


Some view of the final bracing


Some view of the final bracing


Some view of the final bracing


Some view of the final bracing


In order to reduce the weight I trim the UTB a bit and the reduce the plantilla to actual size with not much overhang.
I also shape and thin the soundhole donut to reduce the weight.
Finally after all the sanding and trimming I am able to reduce to 189.5 under 190g.
My previous top was 188 I believe, at least I am to get it under 190g.
I really like the look of the donut ring.



Weight reduced to 189.5


The donut ring profile is now more streamlined.


Close up look