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Which do you do? Why so and what do you use?

Here is my take on it:


http://www.theluthierblog.com/articles/ ... undboards/

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nigel

http://www.theluthierblog.com

Can you tell us your take here?

Stiffer when planed? How do you determine that? Even wood from the same billet can be different. I'm not sure I believe it.

I wonder of planing also crushes cell walls? I have no opinion until I see that paper. And as usual, each piece of wood is different, and its stiffness can be adjusted by bracing. So is there a practical application? I am all for hand work and mostly use hand tools for all woodworking projects.

Ed

I believe you can get exceptional results either way, also some can always find a way to screw things up

The article also stated that sanding after abrasive planing obviated most of the negative effects of abrasive planing. I think most of us sand or scrape our tops after running them through the drum sander. I am not knocking planing tops, just saying a sanded surface may be good enough.

If stiffness deflection is an important element in one's design then use of testing fixture would be a good idea -- it's the stiffness target goal that is of concern not the method or process. It stands to reason that abrasives leave grooves so when measured we are catching the peaks -- so a planed board has more "actual" surface area -- but so what? It's the deflection not the thickness measurements or process that count.

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Ken Cierp

http://www.kennethmichaelguitars.com/

I consistently find that my planed tops are stiffer than tops sanded to a lesser thickness

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Doug

Don't let fear or common sense stop you from trying to build something

I use a hand plane, always have always will. I enjoy the process but I certainly don't claim any sonic advantage. I like the relatively quiet shop environment and they take up little space.
Actually I use two different planes: a wooden Plane for removing the majority of the material, they are lighter and therefore 'fast', less tiring in use. I finish off with a metal smoothing Plane that has been set fine.
I don't sand internal surfaces, they are either finished with the Plane or the scraper. The outside surfaces are sanded but if I had it all my own way they would be scraper finished. I like the way that Spruce takes on that Corduroy texture, the organic feel. It still seems like wood. Unfortunately the commercial market sees things differently. Personally I think they are missing something.

Block plane and scraper, because I don't have room for a thickness sander.

For spruce, I think a planed and French polished surface is the ultimate ideal for clarity and depth (and snobbish showing off ). But for redwood, which is my favorite, I prefer the texture of scraping. And I don't have any planes that can produce a finished surface while planing in any direction through any wood, which is necessary for leveling a rosette, so thus far I've been scraping spruce as well. One day though, I'll achieve that flawless surface

About the extra stiffness thing, only the last little bit would really need to be planed to remove the crushed subsurface cells, which is kind of necessary anyway due to the deep scratches from coarse sandpaper. If you need to remove 1/16" or something from a rough sawn top, I don't really see a reason to plane the whole way if you have a choice.

Trevor Gore goes into it a bit in his book.

The underlying point is that by planing vs sanding, you can achieve less mass for the same stiffness in any given top.

I've never been able to make the planes work for me, so drum sander it is...

Did you read the post, and the linked pdf?

http://www.theluthierblog.com/articles/ ... undboards/

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nigel

http://www.theluthierblog.com

I'm not claiming any sonic advantages either, just putting it out there...what use folk make of this is up to them. Thousands of good guitars are made with sanded tops, I know, I've made a few hundred myself, but could they have been better?

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nigel

http://www.theluthierblog.com

No idea. You might be able to measure these things but it doesn't always follow that we can hear them. But really I've no idea.

AlanC wrote:
Can you tell us your take?

Did you read the post, and the linked pdf?

Seems the link is not a PDF but rather an advertisement page

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Ken Cierp

http://www.kennethmichaelguitars.com/

Think you're clicking on the wrong link Alan.

This is the link in the middle of the post:

http://128.104.77.228/documnts/pdf1986/murma86a.pdf

If you read that, the post may make a bit more sense.

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nigel

http://www.theluthierblog.com

I plane tops by hand because I don't have a thickness sander. I would like to plane backs and side by hand but found that to be significantly harder to do, depending on back/side wood. Mahogany is easy but african blackwood is impossible.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

That is not the link in your post

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Ken Cierp

http://www.kennethmichaelguitars.com/

Yes it is! In order to repost it here, for you, I clicked on it. I've no idea what you're clicking on.

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nigel

http://www.theluthierblog.com

here's your original post

Which do you do? Why so and what do you use?

Here is my take on it:


http://www.theluthierblog.com/articles/ ... undboards

_________________
nigel

http://www.theluthierblog.com
http://www.nkforsterguitars.com/book/

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Ken Cierp

http://www.kennethmichaelguitars.com/

Nigel's original post was correct, in terms of the link to the article, not sure what the problem is. The article is pretty interesting, but it does raise the question of whether the surface damage is going to survive final sanding. The photo-micrographs show damage in layers on the order of a few cells thick - in a practical sense, does this all get sanded away?

I think it's a good topic, as I don't know the answer.

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Jim Kirby
kirby@udel.edu

Couldn't one surface a piece of wood using their standard process and then take a sample of it and look at it under a microscope. Maybe hand plane one sample and sand another.

Pete

I've seen a post or posts pointing out the article before. See http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=35792&p=470340&hilit=murma86a#p470340
The finest grit used was 150, many of the tests were with 80 grit.
Anyone here stop at 80 grit, or even 150?
Article itself states that
But it does not investigate the results of removing the damaged outer layer of cells by, say, hand or ROS finish sanding.
So what happens when you hand plane to thickness and then prepare for finish by sanding, be it by hand or ROS?
I suspect that there will not be much difference at the end between the two methods if both are done with care.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

It is possible to finish Spruce with the hand Plane, going straight to the finish. It will be as smooth as virtually any abrasive. With runout and bookmatched Tops that becomes less and less likely.
You can also sand and finish off with a scraper. The scraper will remove any scratches left by the coarse grit. There are a few ways of getting to the same end result.
But if you really want to see what 240G does to Spruce, sand it to that level and finish it in something like Danish Oil. You might be surprised just how many scratches remain in the wood. Finishes like Shellac tend to fill in and hide these scratches. Thin Oil finishes tend to highlight them.

Exactly

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Ken Cierp

http://www.kennethmichaelguitars.com/