Thread: Celery Top Soundboard?

Peter, your comments about about eucalyptus that you could not bend into a mandolin shape, brittle and hard to bend, also problems with small splits this is feed back I get I hope some one finds a way around this as it is an excellent tonewood.
Density 613 - sound volocity 5262.
So it is a species that needs more research.

Originally Posted by mandoman

Bob

I have some good old Tassie Eucalypt sitting here ready for a one piece back. Big wide boards cut perfectly on the quarter. I read with interest the results others get with it since I need to decide what top to use with it. I gave up on Tassie Eucalyptus a few years ago because it just would not bend into a mandolin shape. Brittle and hard to bend on the hot pipe and a few choice words were said. Also there were problems with lots of small splits that drove me mad, but that back does have a really good ring to it so is quite promising. I played one of Joe Gallacher's guitars a few years ago that had what looked like an Ash back and it was one fine sounding guitar. Have got some better quality timber now so is worth a try again. So much to try, and so little time.

Peter

Well one way around the bending problem is to not use Eucalyptus for the sides. I have some Myrtle that looks quite nice with the Tassie Eucalyptus, and Myrtle is easy to bend. The small splits I suspect was caused by poor drying technique, but then can't be sure because I did not dry it. Myrtle can also develop lots of small splits if dried too quickly. The extremely dry Canberrra summer (drought) weather has caused me to put some nice Tassie Myrtle up the chimney. We recently moved to Bega so probably won't have that problem here.

Peter, your comment that you could use myrtle for the sides with the eucalyptus
there is a fair bit of difference between density and sound volocity with the two species would this cause problems.?
Regards,Bob

I have not used it myself but some have had success using veneer softeners before bending.
Supersoft2 in the USA
Or veneer softener from rivergum timbers in Australia
Rivergum Timbers - Veneer Softener

generally applied the day before bending and allowed to dry.

Bob, I very much doubt it would make any difference at all. The sides of a mandolin contribute little to the overall sound, the top and back are by far the most important sound contributers, but the neck can also contribute a little, When you take the width of a side (~35mm), and subtract the height of the linings (20mm) there is only 15mm of side material that is not rigidly clamped,

Well they you go, I learn something every day Peter,
Do you stain your mandollins.?
As it would look strange unless the colours were close between the myrtle & eucalyptus as you can find white myrtle very close in colour to eucalyptus.

Originally Posted by mandoman

Bob, I very much doubt it would make any difference at all. The sides of a mandolin contribute little to the overall sound, the top and back are by far the most important sound contributers, but the neck can also contribute a little, When you take the width of a side (~35mm), and subtract the height of the linings (20mm) there is only 15mm of side material that is not rigidly clamped,

I don't normally stain the Aussie timbers because they have enough natural colour, and I much prefer the look of natural colours over stain. Look at this one recently finished. Not a drop of stain nor any plastic on it, and if you have any figured Blackwood that colour, let me know.

Mandolins By Peter Coombe - Recently completed instruments

I do stain the ones I make from the traditional Maples.

Peter

Peter, that looks beautiful excellant combination of colours this works real well.
And as to your question do I have any figured blackwood that colour.
I will send you some photos to look at within the next couple of days.
Cheers,Bob

Originally Posted by mandoman

I don't normally stain the Aussie timbers because they have enough natural colour, and I much prefer the look of natural colours over stain. Look at this one recently finished. Not a drop of stain nor any plastic on it, and if you have any figured Blackwood that colour, let me know.

Mandolins By Peter Coombe - Recently completed instruments

I do stain the ones I make from the traditional Maples.

Peter

Jeff, lets both keep our cool this time around.
I spent some time with Gary Rizzolo last week, listening to the guitar with the celery top sound board, with a good sound and lots of volume, the only thing Gary says he does different with Celery top is make it a bit thiner.
While I was at Garys place, Cary Lewincamp called round to visit.
Cary Lewincamp Simply Beautiful Music
Cary has agreed to do a sound track with the guitar as soon as possible.
I note in a thread in the A.N.Z.L.F. that you watched the D.V.D. twice by Ervin Somogyi voicing the guitar and you say in truth that you were not enlightened, I note that you are a ex engineer, do you have an engineer set mind.? in other words if celery top is too dense it will not work as a soundboard.? reminds me of an IQ test that I had when I was young moving to a new high School in England after my family moved down from Scotland where I was born, me and the others in the class were given a board with different shaped holes and a bunch of different shaped pegs and asked to fit the pegs into the holes, they reckon that you can not fit a square peg into a round hole, you can when you excuse yourself and ask the teacher if you can go to the toilet and instead go to the wood work class and borrow a hammer and believe me you can fit a square peg in a round hole, you just have to hit it hard, the moral of the story that is true, is a got 6 of the best with a leather strap that is what they did in them days, but I proved my point. So we will now wait for the sound track with the celery top soundboard that will prove the point, you just have to know what you are doing and try it.
Cheers,Bob
It is worth looking at the properties of some common soundboard woods and comparing them to what Celery top has to offer

Western red cedar 380kg/m3 Modulus of Elasticity 8,3 GPa
Sitka Spruce 430.................... 11
Bunya Pine 460 ......................13
Celery Top Pine 650 ................12

So compared to sitka, your wrc is lighter and a bit less stiff so you make it a little thicker to compensate and still end up with a lightweight top.
Your bunya is a little heavier, but 18% stiffer so the soundboard can be made a little thinner and still be an acceptable weight.
Then you get to the Celery top. 51% heavier and only 9% stiffer so you can't thin it much

So the end result is a soundboard nearly 50% heavier than a spruce board Which is pretty significant both for volume and high frequencies.[/QUOTE]

Unfortunately Bob soundclips do not prove anything except the skill of the person doing the recording.
Not a set mind Bob, but the experience of luthiers all round the world has led to an understanding that a lightweight guitar soundboard is important and celery top does not meet that criteria.
It is not just a matter of knowing what you are doing and trying it, The basic properties are not there.
Must be both of our early years in Scotland that make us stubborn.
regards
Jeff

Must be both of our early years in Scotland that make us stubborn.
regards
Jeff

Point taken Jeff.

Must be both of our early years in Scotland that make us stubborn.

Well I come from a scientific background and that probably makes me just as stubborn. Theories mean nothing until supported by evidence obtained by experimentation. If supported by enough evidence then a theory becomes accepted as a truth, maybe even a law. However, it only takes one experiment that disproves the theory for everything to come crashing down. Maybe the experiment will support the theory, in which case it is more likely the theory is true, but never proven as a mathematical proof can be proven. If the experiment is not done, you will never know.

brava

Originally Posted by mandoman

Well said Peter,
I only wish Jeff could come round and visit Gary and see this guitar and listen.




Well I come from a scientific background and that probably makes me just as stubborn. Theories mean nothing until supported by evidence obtained by experimentation. If supported by enough evidence then a theory becomes accepted as a truth, maybe even a law. However, it only takes one experiment that disproves the theory for everything to come crashing down. Maybe the experiment will support the theory, in which case it is more likely the theory is true, but never proven as a mathematical proof can be proven. If the experiment is not done, you will never know.

Hope you dont mind me bringing this up again Jeff,
I have had a bit more feedback from customers using Celery top as a sound board and all of them are happy with the result, and to allow for the density finished there soundboards at 2.3 thickness, so it does work it just needs to be worked different.
Regards, Bob