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H.R.Fisher

Thin top /high density?

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l will put it together and string it up in the white ,glueing the top on very lightly and see how it performs .        If it doesn't work I can still take it off and replace it. I'm doing this as a hobby,I'm not tied to any time or financial constraints.     Again , thanks for all your helpful responses.

                                                                                                                   The best to you all

                                                                                                                                         Henry

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23 hours ago, Don Noon said:

 

Belly_Mode_5_nodal_lines.jpg.5b86c8f15545c75eb9f6189fa5c2c8bd.jpg

 

21 hours ago, uncle duke said:

imo - the above is the work of the worlds greatest living maker. 

Surely Don is a great maker - however what is so special in these nodal-lines ?

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1 hour ago, Danube Fiddler said:

 

 

 

Surely Don is a great maker - however what is so special in these nodal-lines ?

  Firstly, I'm thinking along the lines of Sean Connery mentioning a few words in a movie he once co-starred in - "trade secrets my boy"

  Our best chance of really ever knowing is to beg or persuade Fiddlecollector to drive down from Milton Keynes to ask the man himself what we mere mortals here need to know about these nodal lines. 

  If the man himself has a case of what I call "Ozzy Osborne syndrome" or in other words "if you're not English, I'm not telling",  most of us will never know.  

He's not a telling, just a selling for the time being, I'd think.   

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On ‎6‎/‎16‎/‎2018 at 3:29 PM, H.R.Fisher said:

 It's real  spruce wood! I' m a bit suspicious that my tonewood supplier is getting rid of some of his undesirable stock thinking this novice won't know any better.[which may have been true]  From  now on I will be specifying the density prior to purchasing it. 

Did your tonewood supplier know that the density was .52?

Maybe not? I doubt if many tonewood suppliers actually know what they are selling, otherwise they would be more picky about what they were getting from the loggers, which in your case is either tension wood or more likely compression wood?

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13 hours ago, uncle duke said:

  Firstly, I'm thinking along the lines of Sean Connery mentioning a few words in a movie he once co-starred in - "trade secrets my boy"

  Our best chance of really ever knowing is to beg or persuade Fiddlecollector to drive down from Milton Keynes to ask the man himself what we mere mortals here need to know about these nodal lines. 

  If the man himself has a case of what I call "Ozzy Osborne syndrome" or in other words "if you're not English, I'm not telling",  most of us will never know.  

He's not a telling, just a selling for the time being, I'd think.   

Sorry, completely dont´understand, what you mean. My poor knowledge of the english language probably is an explanation.

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3 hours ago, sospiri said:

Did your tonewood supplier know that the density was .52?

Maybe not? I doubt if many tonewood suppliers actually know what they are selling, otherwise they would be more picky about what they were getting from the loggers, which in your case is either tension wood or more likely compression wood?

I believe the job of tonewood suppliers is not an easy job. However my experience is, that they know very good, what they are selling. I know one, who didn´t need one second of time to recognize, that I had found a really sensational piece of spruce in his stock while I needed hours of later examinations at home to come to a similar judgement.

However the tonewood-suppliers often don´t know so exactly, what they are buying - they can recognize exactly only after cutting the logs.

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16 minutes ago, Danube Fiddler said:

Sorry, completely dont´understand, what you mean. My poor knowledge of the english language probably is an explanation.

If Don will permit, thanks in advance.

Don borrowed that image from the website platetuning.org..   If one chooses to be a believer in plate tuning and chladni patterns while carving wood the spruce plate presented here for example would be something to strive for while carving his own wood.

All I can comment about from past experiences is the area below the lower sound hole lobes.  Go too thin there and you get a poor sounding plate, I believe, along with a contributor of unwanted wolf notes after stringing up the fiddle, though not a major contributor of wolf notes.  Why add to the agony? - get that area rightly shaped.

If we as makers try moving interior contours lines to match his chladni plate example just using roughshod scraping and thinking methods chances are we'll ruin a lot of good tonewood in the process and still show up here at Maestronet proud as ever with something for a violin plate we really don'y know anything about.  So yes, I'm admitting I really don't know the answers we need.  All I can offer is food for though for the time being.

    I'm not saying he, Hutchins and possibly Morel and the rest didn't ruin wood while running tests.  They more than likely did.  If the maker of the example plate is a member here he disguises himself very well.  He's the same age as my own father so I realize and try to compare what these two old guys may be thinking and doing even though they are thousands of miles apart.  All I've learned about that is somedays just leave these guys alone and don't interrupt the piece and tranquility they're trying to find, if not found already.

For some reason when I was younger learning foreign languages Danube Fiddler the italian, spanish, some portuguese and some french were almost second nature for me - they felt natural.  But the learning of the german lanuage was something that was very difficult, if not impossible for me. 

  I will make my future comments to you easily legible in the future.

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44 minutes ago, Danube Fiddler said:

I believe the job of tonewood suppliers is not an easy job. However my experience is, that they know very good, what they are selling. I know one, who didn´t need one second of time to recognize, that I had found a really sensational piece of spruce in his stock while I needed hours of later examinations at home to come to a similar judgement.

However the tonewood-suppliers often don´t know so exactly, what they are buying - they can recognize exactly only after cutting the logs.

Last time i asked for the spruce density from a supplier, he replied: 10-12% :lol:

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7 minutes ago, Danube Fiddler said:

I think, you remember wrong - he was a wine supplier !:rolleyes:

that's it! it was quite dense wine as i remember, but fully seasoned  :D

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And what is your opinion about these two pieces? The biggest difference is the frequency. Which piece will be better? Besides, I am asking for information - what is the factor in C19?

image.png.4061b89f8ae06c711e601a9975fe748e.png

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21 minutes ago, Szymon said:

And what is your opinion about these two pieces? The biggest difference is the frequency. Which piece will be better? Besides, I am asking for information - what is the factor in C19?

image.png.4061b89f8ae06c711e601a9975fe748e.png

Both wedges are on the heavy side, but not nearly as heavy as Henry's 0.52. But i believe even some Strads had 0.46 tops.

C for wedge 1 seems pretty high, for wedge 2 normal/lowish?

What is meant by ring M and Hz/cm3?

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C is the speed of sound of the spruce, measured by Don Noon's (ridiculous easy ^_^) way by tapping one end of the wedge, looking for a sensible frequency peak = F, multiplying by 2x the length L. C is in m/s. I understand C for spruce is usually between 5000 and 6000 m/s, so 7000 m/s is pretty high.

The radiation ratio for wedge 1 would be 7062 / 450 = 15.7 which is high too. (so good according to some)

Wedge 2 has a RR of 5508 / 460 = 12, which in turn is quite low.

edit: that is when those C's do belong to wedge 1 and 2 in the right column.

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Figure 1 just shows what the sizes A1, A2, B1, etc. stand for (the sides of the wedges), so it applies to both wedge 1 and 2.

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1 hour ago, Emilg said:

I understand C for spruce is usually between 5000 and 6000 m/s, so 7000 m/s is pretty high.

The highest I have seen for non-torrefied wood has been in the 6200 - 6300 range, and that was for 30 year old stuff.  So I have to think that 7000+ is bogus.

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7 hours ago, uncle duke said:

  I will make my future comments to you easily legible in the future.

Hi uncle duke,

thanks for the long "translation" !  If I now understand a little bit better (however not yet sure) you wanted to give a warning not to target these or any nodal-lines ?

In my own experience nodal-lines are difficult to change with only a little use of scrapers. To really change them you need a plane and have to plane a lot. I like it very much to find these nodal-lines, not by Chladni but only by tapping. If I have the nodal - lines, I can determine the M2 or M5 - frequencies much better. I believe, that nodal lines reveal a lot of the wood properties much more than effects of graduations. For example the relation of longitudinal / radial e-moduli as also grain - course related effects. 

I could imagine, that these makers, who regularly monitor the nodal-lines of e.g. M2 and M5 also during the graduation process, can learn a lot about their used woods as also about their graduation processes and eventually define new targets. 

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8 hours ago, uncle duke said:

If we as makers try moving interior contours lines to match his chladni plate example just using roughshod scraping and thinking methods chances are we'll ruin a lot of good tonewood in the process

If one has also some other deadlines in the process as stiffness-numbers, normal graduation-ranges, weights, normal areas of mode-frequencies, then one will not ruin good tonewood so fast. However possibly one should be ready to ruin wood from time to time to find out some more.  

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4 hours ago, Don Noon said:

The highest I have seen for non-torrefied wood has been in the 6200 - 6300 range, and that was for 30 year old stuff.  So I have to think that 7000+ is bogus.

Hi Don,

why I nearly always find so many peaks in your sound-speed-examination way ? I have chosen the highest peak for determination of sound-speed. But what´s about the other peaks ? In this case I calculated 5300 m/s and a RR of 13,9. The M5-frequency later came out surprisingly high ( 70g before f-cut and BB / 386 Hz and 160 Hz [M5, M2] / rel. stiffness[Dr. Harris] = 1,24 / graduations del-Gesu like with a little bit more thickness in center [3mm] ). 

Done something wrong ?

Soundspeed.thumb.png.90ca293bb75325952ebc95005ad52b63.png

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