Some materials benefit from stiffening with epoxy, xps for instance, but I am not sure we should be painting every material with the same brush 😁.
I have always said I am not making a musical instrument with an intended sound, but a panel with no sound of its own, hopefully.
I have just coated one of my crate ply panels in pva, not because I think it is going to make a great transformation into a fantastic sounding panel , but just to see what happens.
I don't think this material will benefit from a harder surface, as I think the flexibility is a good thing ?
PVA isn't that rigid so hopefully will still allow the panel to flex , but will it help to reduce some of the materials self noise ?
A lot of this panels problems are coming from the exciter itself I believe, but is trying to damp the panel to solve the problem the right thing to do ?
Some plys are very rigid already so applying a more rigid surface could make things worse ?
But I suppose until all options have been tried , we have no idea what is the best option.
Trial and error.
And everyone will have their own idea of the perfect sound for them, of course ?
Steve.
I have always said I am not making a musical instrument with an intended sound, but a panel with no sound of its own, hopefully.
I have just coated one of my crate ply panels in pva, not because I think it is going to make a great transformation into a fantastic sounding panel , but just to see what happens.
I don't think this material will benefit from a harder surface, as I think the flexibility is a good thing ?
PVA isn't that rigid so hopefully will still allow the panel to flex , but will it help to reduce some of the materials self noise ?
A lot of this panels problems are coming from the exciter itself I believe, but is trying to damp the panel to solve the problem the right thing to do ?
Some plys are very rigid already so applying a more rigid surface could make things worse ?
But I suppose until all options have been tried , we have no idea what is the best option.
Trial and error.
And everyone will have their own idea of the perfect sound for them, of course ?
Steve.
Leob.
Sorry, I forgot to say thanks for posting the reverse picture , thank you.
I look forward to seeing how you brace the exciters.
and how well the panel takes the power you are going to be putting into it ?
Hopefully we can get some measurements and maybe a recording at a later date ?
Steve.
Yesterday I test coated a piece of crate ply with egg whites to see how it affected the material.
To me it felt stiffer, so to make sure I have coated another piece ,but not ply this time .
I have only coated half of the strip of wood with egg white , which has given the wood a more golden sheen.
I forgot to clean the brush straight away , which was now getting very hard, cleaning with soap and water eventually worked.
This made me think how would egg whites be as a glue, so have now glued a strip of crate ply to the strip.
I will leave it there till tomorrow to dry.
I'm just curious, but we all know what that did to the cat 🙀
Steve.
To me it felt stiffer, so to make sure I have coated another piece ,but not ply this time .
I have only coated half of the strip of wood with egg white , which has given the wood a more golden sheen.
I forgot to clean the brush straight away , which was now getting very hard, cleaning with soap and water eventually worked.
This made me think how would egg whites be as a glue, so have now glued a strip of crate ply to the strip.
I will leave it there till tomorrow to dry.
I'm just curious, but we all know what that did to the cat 🙀
Steve.
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Decided to make bracing part of the construction holding the 4 plates. Vacation starting today, so gonna get the rest of the materials needed tomorrow and should get amps next few days. So will get started building the first stack now and when that is done I will analyze that, and can make a recording as well.
Hello Steve
Thank you for testing! Let us now. The first goal listed is rising the grain to help in sanding.
Warping/Stiffening etc:
Thought I'd pass on that I've also tried using very light braces to flatten panels.
I used 3mm ply on edge about 8 to 10mm deep and tapered the ends as per guitar bracing..glue in a pattern which suits the panel and the warp.
It appears to work...just enough stiffness to heep control of the panel without affecting the performance
Suggest give it a go
Cheers
Eucy
Thought I'd pass on that I've also tried using very light braces to flatten panels.
I used 3mm ply on edge about 8 to 10mm deep and tapered the ends as per guitar bracing..glue in a pattern which suits the panel and the warp.
It appears to work...just enough stiffness to heep control of the panel without affecting the performance
Suggest give it a go
Cheers
Eucy
Yes it seems that the egg whites does have a stiffening affect on the wood and card, a bit like starching a shirt(now there's an idea)
be warned ,I found my dog sniffing and licking my test pieces(that does not sound right 😲, it's like an egg lolly to the dog 😂
the egg whites soak into the wood and give the white wood grain a nice golden sheen highlighting the grain.
The egg whites soaking into the wood took all of the whites away from the joint I was trying to glue, same problem I had with the pva and the canvas.
I'm not too worried about sanding to a guitar finnish, so that is about how far I will be taking it.
Steve.
be warned ,I found my dog sniffing and licking my test pieces(that does not sound right 😲, it's like an egg lolly to the dog 😂
the egg whites soak into the wood and give the white wood grain a nice golden sheen highlighting the grain.
The egg whites soaking into the wood took all of the whites away from the joint I was trying to glue, same problem I had with the pva and the canvas.
I'm not too worried about sanding to a guitar finnish, so that is about how far I will be taking it.
Steve.
I think there might be one other option for a Egg White.
I am thinking a Meringue Flat Panel with a strengthening embedded, maybe a webbing scrim tape.
Flat Meringue is usually formed as a result of the mixture being incorrect and if fails to raise in the oven, the incorrect mixture can also have elastic properties when cooled.
I am thinking a Meringue Flat Panel with a strengthening embedded, maybe a webbing scrim tape.
Flat Meringue is usually formed as a result of the mixture being incorrect and if fails to raise in the oven, the incorrect mixture can also have elastic properties when cooled.
JohnnoG.
It wouldn't be the dog eating the panel ,it would be me 🤣
One thing I have noticed with the crate ply is a harshness in the upper frequency.
I also noticed when measuring, that the frequency rises above 10k off axis.
See rough picture ,dotted line off axis.
The panels are close to walls and objects, so I could be getting strong harsh reflections?
I had a eps panel with a similar problem.
I think today I might add a fabric dome(dust cover) to the exciter and see if this helps?
Steve.
It wouldn't be the dog eating the panel ,it would be me 🤣
One thing I have noticed with the crate ply is a harshness in the upper frequency.
I also noticed when measuring, that the frequency rises above 10k off axis.
See rough picture ,dotted line off axis.
The panels are close to walls and objects, so I could be getting strong harsh reflections?
I had a eps panel with a similar problem.
I think today I might add a fabric dome(dust cover) to the exciter and see if this helps?
Steve.
I had forgotten about these two.5mm pieces of veneer I found in my shed.
I'm still thinking of what to do with them .
One long 34cm panel with the grains going the same way.
Or two square 17cm panels but one going with the grain and one crossing grains.
I'm in no hurry as , as usual I have too many projects on the go at the same time 🤯
Steve.
I'm still thinking of what to do with them .
One long 34cm panel with the grains going the same way.
Or two square 17cm panels but one going with the grain and one crossing grains.
I'm in no hurry as , as usual I have too many projects on the go at the same time 🤯
Steve.
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Hello Eucy,
May I ask for a drawing or a picture... or more explanations...I have difficulties to figure out what you did. Low CPU (brain) power tonight for me?
Christian
Hello Steve,
Yes, it was already shared : DML is in some way the art of the right stiffness and not a race to the stiffest material.
And also right, we have few other possibilities than trials to close options. Our (collective) imagination being wide, the possibilities are numerous; happy is the one who knows how to make the right choices.
Christian
Steve,
The egg white is supposed to fill the grain. Then shellac comes. It would perhaps be less tasty for your dog!
Here is an other link to egg white filler used by a violin maker. Some posts mention adding salt or even vinegar!
Another reminds that white egg was used in the early time of photography to seal the paper (usually cotton) to make print. See albumen print in Wiki.
Here Alternative Printing Process: Albumen Print the process is more detailed with one tea spoon of salt per egg and a one night rest before using - the egg is more fluid.
So is there a problem between some salt and shellac?
No idea where it leads but this research has some fun.
Carbonara pasta use only the yolk. We know what to do with the white! Saying that my favorite recipe with remaining white is the little cake named "financier" made with almond powder, egg white, sugar. Easy to do, very tasty, many possible variant. I recommend it. Don't worry my intention is no to transform this thread in a one about cooking... only DML cooking.
Christian
Hi Christian
Pic of the rear of a test panel
Stiffener at free top and bottom edges
Sides taken care of in other ways
Yellow trace paper on rear
Damping by very thin adhesive felt used for drawers
Exciter supported by damped cable tie glued to panel..Tape for temporary/permanent extra hold
A bit rough in finish but unseen
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Thank you Eucy
Understood!
In my test panels, the exciter is supported by the wires that go up.
Christian