View previous topic :: View next topic |
Author |
Message |
Dave Chandler Super Member
Joined: 31 Oct 2007 Posts: 691 Location: Mt Mitchell in North Carolina
|
Posted: Wed Oct 31, 2007 3:24 pm Post subject: Effects of Sunlight on violin plates |
|
|
I've been reading a number of authors that talk about setting their plates out in the sunlight to improve the tone. Does anyone have any experience with a "grow" light? I've been setting my recent work under a grow light and can't tell that its having an impact (except on my electricity bill). I put my plates out in the sunshine and then worry all day I'll forget to bring them in. I have seen immediate effets under direct sunlight, but under the lamp it seems unnoticeable. I have not read anywhere what particular rays have an impact on the tone, maybe a black light would work better? _________________ Dave in the Blue Ridge
Southern Violin Association
"Success is the ability to go from one failure to the next with no loss of enthusiasm" Winston Churchill
"I took the road less travelled, and now I don't know where I am." Marco Polo |
|
Back to top |
|
|
Andres Sender Super Member
Joined: 23 Mar 2007 Posts: 275 Location: N. CA
|
Posted: Wed Oct 31, 2007 8:31 pm Post subject: |
|
|
I don't recall that a 'grow light' is a particularly good source of UV, which is usually considered for our purposes to be the useful part of the spectrum.
Black lights are slow but they have enough effect to dry many varnishes and darken wood somewhat. A lot of pros use suntanning bulbs which are more powerful.
If you get good sun, it will be hard to beat the natural light without getting into some dangerous and expensive bulb types.
As to tonal effects, I have no idea whether the sun has an effect, or whether that effect can be duplicated by bulbs. What authors made the claim about sun and tone? |
|
Back to top |
|
|
FiddleDoug Member
Joined: 08 Sep 2007 Posts: 227 Location: Hilton, NY
|
Posted: Wed Oct 31, 2007 11:44 pm Post subject: Reptile bulbs |
|
|
I've thought about using the florescent bulbs used by people that raise reptiles. They apparently have high outputs of both UVA and UVB that are needed by some reptiles. I think that blacklights are just UVA. _________________ Doug Wall
www.wallindependent.com |
|
Back to top |
|
|
Dave Chandler Super Member
Joined: 31 Oct 2007 Posts: 691 Location: Mt Mitchell in North Carolina
|
Posted: Fri Nov 02, 2007 12:23 pm Post subject: More on sunlight |
|
|
I was reading an article about a maker named Alfio Batelli - he's a no-show in maestronet database . Anyway, he claimed that he left his violins out in the sun for 3-4 hours a day, for about a month, before finishing, claiming that it enhanced the tone the equivalent of 5 years of steady playing. I've visited other makers websites and many fine- tune their plates using sunlight. Not so sure about the prolonged exposure. And now that I've looked for him in maestronet database and found nothing perhaps it needs to be taken with a grain of salt. My problem is I'm making one at a time, and after two weeks with many cloudy days my impatience is calling me to get this assembled so that I can get the finish fully cured by Christmas. _________________ Dave in the Blue Ridge
Southern Violin Association
"Success is the ability to go from one failure to the next with no loss of enthusiasm" Winston Churchill
"I took the road less travelled, and now I don't know where I am." Marco Polo |
|
Back to top |
|
|
Andres Sender Super Member
Joined: 23 Mar 2007 Posts: 275 Location: N. CA
|
Posted: Fri Nov 02, 2007 5:49 pm Post subject: |
|
|
Fine tune their "tuning" or their appearance?
People suntan instruments all the time to get some color in the wood. Claims regarding effects on the tone aren't very common. |
|
Back to top |
|
|
jethro Member
Joined: 07 Apr 2007 Posts: 178
|
Posted: Sat Nov 03, 2007 3:13 am Post subject: |
|
|
I remember reading someone talking about exposing plates to sun uv,
and measureing the tap tone as he did it. He said it lowered the frequency
gradualy. He used the sun to adjust the tap tone. Can't remember who
it was but I found it on the web somewhere.
I should think it would be the "hardest" uv causing the changes. Most of
the bulbs probably can't generate the higher frequencys.
Shine a flashlight through a plate in the dark -- you can see through the
plate. I have to think the UV may be going all the way through too, or at
least to the inside somewhere. Hard uv can distroy allmost anything man
made. It is what kills plastic lawn furniture. The UV is probably slowly
distroying the mechanical structure of the wood which shows as the tap
tone going down. I can't immagine this being a good thing for the wood.
Maybe just adjust the tap tone other ways.
I think you can find this fellows research thorough google - I think I found
it that way.
You could get and install a "solatube" in your shop roof. It is like
a chrome plated stove pipe which brings reflected sunlight right down
to you - UV and all !
TIM |
|
Back to top |
|
|
Marijan Radaljac Junior Member
Joined: 04 Nov 2007 Posts: 1 Location: Slovenia
|
Posted: Sun Nov 04, 2007 8:44 am Post subject: |
|
|
Tim,
I would say that there is no specific efect of sunlight UVA wave spectrum on the tap tones of the free plate. I think it is simply a mather of dry out which will hapend under the direct sunlight and heat. By that the specific density of wood cels structure in a same volume of the plate will change and make it lighter, which will cause the change of the plate pitch. Same would hapend if you keep the same specific density and thin down the plates.
You would achive contra efect if you soak the plate in a bath filled with thin gipsum or some other stuf, let it dry and the pitch will change in other direction. Up.
That is what I think it is going on. _________________ Marijan
www.violineradaljac.com |
|
Back to top |
|
|
jethro Member
Joined: 07 Apr 2007 Posts: 178
|
Posted: Wed Nov 07, 2007 3:29 pm Post subject: UV |
|
|
Marijan:
Yeah, this thing I read could have been just somebodys Idea with no real
testing to see if it was really happening ! I would think de would have had to UV the plate in a sealed plexiglass box with some way to keep the
humidity and temp. constant to say if it was the UV or the bake-out effect.
If I was still in college I could have tried testing how far the whole spectrum of UV can penetrate through spruce. They had some nice
spectrophotometers that could have printed out a nice graph. !
(maybe a good theses for a graduate student in optics ? )
Tim |
|
Back to top |
|
|
violinarius Member
Joined: 14 Dec 2007 Posts: 171
|
|
Back to top |
|
|
|