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Jim Bress

The Bress Bench

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That looks really good Jim.  The color match is pretty good.   And the wood on the back is a nice match too.  I've never tried to copy anything down to the wood.  I haven't had any luck getting a sound analysis program on my Mac.  I had a nice, extremely easy to use one for tuning Japanese flutes about 15 years ago, but not any more.   My 405 long  Gofriller Viola is 620 grams all fitted up with a chinrest and everything.  If I blow through the f holes it sounds like 360 on an online tone generator.  Maybe it's really half that.  Tapping over the bottom block it sounds 370.  Tapping the upper block it is a fifth higher.  Don't know what that means!  

The bigger one, somewhat bigger than yours, but with a lower arch on the front.  (The Gofriller has yours beat by 3 or 4 mm!) is a whopping 660 g fully ready to play.  It has a very thick back.   It taps lower, maybe 365 at the top, and a fourth lower at the bottom.  Blowing is a little lower than the other.  Maybe 346?  

I like doing violas.  Lots of different styles and sizes.  Have you done others, or is this your first?

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1 hour ago, Urban Luthier said:

Nice work Jim. I like the look. (i feel your pain, This is a tough one to colour match. it seems as if the colour on the Amati comes from beneath the varnish itself

I think your right.  I believe (too lazy to look it up) the varnish analysis in the Estense book said a stain was detected in the wood.  I UV tanned then brushed on and blotted dry a 4% solution of sodium nitrite.  I like the routine.

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1 hour ago, Ken_N said:

That looks really good Jim.  The color match is pretty good.   And the wood on the back is a nice match too.  I've never tried to copy anything down to the wood.  I haven't had any luck getting a sound analysis program on my Mac.  I had a nice, extremely easy to use one for tuning Japanese flutes about 15 years ago, but not any more.   My 405 long  Gofriller Viola is 620 grams all fitted up with a chinrest and everything.  If I blow through the f holes it sounds like 360 on an online tone generator.  Maybe it's really half that.  Tapping over the bottom block it sounds 370.  Tapping the upper block it is a fifth higher.  Don't know what that means!  

The bigger one, somewhat bigger than yours, but with a lower arch on the front.  (The Gofriller has yours beat by 3 or 4 mm!) is a whopping 660 g fully ready to play.  It has a very thick back.   It taps lower, maybe 365 at the top, and a fourth lower at the bottom.  Blowing is a little lower than the other.  Maybe 346?  

I like doing violas.  Lots of different styles and sizes.  Have you done others, or is this your first?

LOL, I didn't notice how well the back matched until that picture.  I really just grabbed a back off the shelf that matched a neck block that was old enough to use.

I'm just starting to record full body modes.  I don't really understand what they mean, but its so easy it seems like a potential lost opportunity to not record them.  Talking to different makers at workshops and shop visits (when my work forces me to travel), I've been learning how different makers make graduation decision points on where and when to remove wood, or not.  It's nice when different methods lead to the same conclusion.  It's like one of statistics mantras I was taught.  If two or three different tests give results that lead to the same conclusion, then you can trust the result of the test.  Otherwise, check your data and reassess how it should be interpreted.

This is my first viola.  I really love the lines of this model and N. Amati models in general.  Hopefully I like how it plays/sounds.  Two more violins and another viola then I'll go off the deep end and make a cello. :o   I've already started the next violin.  Modeled after the Strad 1690 Tuscan.  I also have a drawing of the 1690 Tuscan viola that has similar bout widths, but a bit longer at 413 mm LOB.

45E8E876-085F-49C2-8267-1E68AB6F3716.thumb.jpeg.ae8431907bfcf9c117ba3c414e7d443b.jpeg

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Hey Jim! your viola is looking real good! I finally got back to work in the shop and the garland is done on the viola. I have a couple of questions I'd like to PM you about.

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I finished varnishing 3 weeks ago.  Giving a little extra time to make sure the varnish was well cured, then flattened and polished the varnish this weekend.  I re-set the sound post that fell during the processed and re-weighed and ran another spectrum analysis to see how things have changed.  The weight of the varnish and ground is 17.2 g.  AO essentially stayed the same which makes sense (I guess).  B1- and B1+ both went up quite a bit.  What it means, not a clue, but easy measurements to take.

AO = 223 Hz (+1)

B-1 = 459 Hz (+39)

B+1 = 684 Hz (+65)

Weight = 540.8 g (+17.2)

 

Viola 20180120.pdf

 

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I think your "B1-" mode is actually the B1+, and what you think is the B1+ is something else.  What you have listed is impossibly high for a viola.

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14 minutes ago, Don Noon said:

I think your "B1-" mode is actually the B1+, and what you think is the B1+ is something else.  What you have listed is impossibly high for a viola.

Hmm, maybe not being strung up yet is a factor. I’ll check it again after setup and try to figure out what mistake I’m making. Thanks for your input Don. 

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Without strings or bridge, the taps have to be downward on the top vs. sideways on the bridge for a strung-up instrument.  That tends to excite the C4 mode, which is probably your 684 Hz peak.  I have taken spectra without strings, and although it is higher, it isn't that much, usually ~5%.  You can get a little more accurate by putting on a chinrest, which makes a difference.

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14 minutes ago, Don Noon said:

Without strings or bridge, the taps have to be downward on the top vs. sideways on the bridge for a strung-up instrument.  That tends to excite the C4 mode, which is probably your 684 Hz peak.  I have taken spectra without strings, and although it is higher, it isn't that much, usually ~5%.  You can get a little more accurate by putting on a chinrest, which makes a difference.

Thanks for the additional info.  I was mostly trying to see the difference, if any, before and after varnish.  With the varnish being the only difference.  I didn't have a chinrest on when I did the first analysis in the white, so adding a chinrest now ruins the comparison.  Actually, I didn't have a viola chinrest at all.  On another note, I got the Plum wood "Tempel model" chinrest.  The plum wood looks really nice and I will probably use it again.

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Final polish of varnish completed last night.  I'm happy for this instrument.  Still not quite hitting my target.  I'm getting closer though. :)

I'm headed to San Diego in mid-February for work.  I'd love to do a shop visit if there are any folks here that wouldn't mind a drop in.

-Jim

varnish_back.thumb.jpg.81830af7f0aa9b1c243a500491800fbc.jpgvarnish_top.thumb.jpg.44240a11b31ab8b51c87509a54143ada.jpg

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Thanks Rue.  Look at the "Regarding varnish..." thread.  I posted a picture of a violin that has the varnish characteristics that I'm aiming for.  I have an old fortune cookie proverb that I keep taped to the wall.  "The odds of hitting your target go up dramatically when you aim at it".  For me, following that advise has been a great help in violin making and life in general.

Cheers,

Jim

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20 minutes ago, Jim Bress said:

Thanks Rue.  Look at the "Regarding varnish..." thread.  I posted a picture of a violin that has the varnish characteristics that I'm aiming for.  I have an old fortune cookie proverb that I keep taped to the wall.  "The odds of hitting your target go up dramatically when you aim at it".  For me, following that advise has been a great help in violin making and life in general.

Cheers,

Jim

I hope you're not missing the tree because of the forest.

I think you hit a bullseye.

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24 minutes ago, Rue said:

I hope you're not missing the tree because of the forest.

I think you hit a bullseye.

Missing the trees?!  I try not to even miss the Abuscular mycorrhizae.  :Pimage.png.a06d39f24481dbce29f12106cbe59007.png

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2 hours ago, Jim Bress said:

I'm headed to San Diego in mid-February for work.  I'd love to do a shop visit if there are any folks here that wouldn't mind a drop in.

I'm the only one I know about it this far South West corner of the country.  This ain't Ann Arbor or NYC.

You're welcome to stop by.

 

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23 minutes ago, Don Noon said:

I'm the only one I know about it this far South West corner of the country.  This ain't Ann Arbor or NYC.

You're welcome to stop by.

 

I'd like that.  It looks like your about an hour away, which is closer than my daily commute.  I'll let you know when my schedule firms up and see if your available. 

22 minutes ago, Alex l. Reza said:

Very nice looking!!

Thanks Alex!

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On 1/24/2019 at 7:40 AM, Jim Bress said:

varnish_back.thumb.jpg.81830af7f0aa9b1c243a500491800fbc.jpg

Lovely varnish color!  It looks like you hit on just the right depth to bring out the chatoyance.
I'd love to come by and see it in person sometime. 

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6 hours ago, DoorMouse said:

Lovely varnish color!  It looks like you hit on just the right depth to bring out the chatoyance.
I'd love to come by and see it in person sometime. 

Welcome anytime.  I'd like to see your shop as well.

-Jim

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