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Preparing for Closing

Well before I can close the box, I need to glue in the side struts, prepare the back brace and glue in the lining and profile the back.
I made the radius stick previously and use it to good effect.
First I just check the profile and bring down the side profile by block plane.
When it's almost fitting then I tape some sandpaper to the radius stick and sand to match.
The back profile is now very fitting.
Next I will need to make 3 back braces and glue in the lining and do the final fitting process again.
I also took the opportunity to do some spring cleaning, as it's near Chinese New Year.
It's customary to do spring cleaning before the CNY.
Well, in a way it's good as it helps to keep my workshop organised.
I did a stock count of the fingerboard blanks and bridge blanks and back/sides tone wood too.

The sanded profile. Noticed the waist area is slightly higher than the rest? If not when the back is glued on, you will noticed a dip in the waist area like a violin waist.

Tape the sandpaper to the radius stick

Sanding in action.

Checking the profile fit.

I took the opportunity to organise my shop. The tone woods stacked nicely.

Not much done but I managed to split the back brace and plane to size and radius the bottom on the radius stick.
After that I cut the notch in the lining block for the 2 back brace.
The lower bout brace pocket is stil not yet done.
After that will be sanding to shape using the radius stick.
I expect the sanding will take some time and effort to get the correct curvature dome.

Splitting the brace

Brace split from the blank

Planed to size and followed the grain orientation

Plane the bottom of the brace to a radius.

Sand on the radius stick to conform to the radius

Fit the brace to the lining side brace block

Another view

I glued up the side struts and fitted the last back braces.
Overall it looked kind of impressive with all the side struts.
Other than the 3 main ones on each side, there are about 5 more in between.
I used the hide which I prepare the other day.

Fitted the 3 back braces

Notch the dentellones for the smaller side brace

All set ready to glue

Applying the hide glue.

Glued and clamped

All glued

After the glue had dried, I remove the clamps.
Boy it looked like a complicated structure with all the side struts...

After the glue had dried. It look complicated with all the side struts especially the 3 big massive ones.

I put in the back brace and check for the fitting with the radius stick.
The back braces form a curve is that more curve than the radius stick.
I have 2 choices after I glue in the lining; to fit with my old way of using the block plane or to sand and shape every thing using the radius stick.
Well till when I put in the lining then I decide the best approach.

Also I shave down the side braces; they are too stout
Well I should have shaped them before I glue them in.
After gluing them in, I can only shape using the violin thumb plane.

The body with the back brace on.

Can see the curvature here.

The shape formed by the LTB & and center back brace and the UTB and 1st back brace, reminds me of the 2 temple gates or some sort. :)

Shaping the side brace.

I managed to glue the lining to the sides and profile the lining after the glue dried.
Since the side struts broke it into section so I do the lining in sections too.
So it was very easy.
After the glued dried the next day I profile the lining with my block plane using the aluminium bar.
Now all set to close the back.
Meanwhile I also too pics of the interior before I close the box.

Applying hide glue to the lining

Clamp the lining with clamps

All glued and clamped

Looking the front.

Between the central back brace and lower bout back brace

Looking at the whole back

Overall view

Looking at the open harmonic brace

This gives me a feeling like a Japanese shrine

Front to back view

Heel block. The spanish foot will support the 1st back brace.

Lower bout side brace with T-nut embedded for side weight addition.

I patch a piece of rosewood to the heel as the heel is too low to match the overall curvature of the back doming.
Well I could have lower the heel abit more but since the rest is already shaped nicely to the doming, I just simply patch a rosewood instead.
It doesn't affect the structure integritty.
After the glue dried, I shape it to conform to the curvature.

Glue one patch for the heel

After the glue dried I plane to to conform to the back doming.

Checking the doming fitting

Top view

Now back is ready for closing. Next to come is to thickness the back and close the box.

Before I closed the box I remembered I have yet to cut the sound port.
And so I bend a piece of spruce for the inner backing and glue it to the right upper bout (bass side).
Then I found my template and trace the pattern to the sides.
Finally I drill 2 holes using the forstner bit and several saw holes and saw thru' them using the coping saw.
Final shaping is by file and sandpaper.

Bend a piece of spruce for inner backing

Glue the piece of spruce to the upper bout

Trace the port shape to the sides

Pattern traced

Drilled the 2 main holes

Unfortunately I drill the lower part too close to the edge of the reinforcement spruce backing. Well it cant be helped now.

Drill somemore smaller holes to help sawing/cutting.

Saw thru them.

Shape the holes

Almost done!

Not much things done since I am back from reservist training.
I thickness the back a bit still quite a fair bit to go.
However I am still thinking of what backstrip inlay to do, in the end I think I just use no backstrip at all since the theme is simplicity for this build.
Before I close, I began to thickness the back.
Once the back got thin enough, it became alive.
So I thin it to about 2.2 - 2.5mm, the rest I'll leave it until I got the brace up.
The weight of the back is about 290g.
Well this is the first time I weight my back so I don't have previous data reference.

Thicknessing the back

Dry run for closing the back

Another view

See the radius of the back it's a smooth curve.

Weight of the back is about 290g. I have to press the tare and see the reverse weight.