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Do you ever use rotten stone during shellac pore filling instead of pumice? If so, when/how? Why do you choose one over the other?

I bought some when I first was buying items to begin french polishing not knowing it was different from pumice. Now I don't know what to do with it.

It's finer than Pumice and can be used for polishing out varnishes/polished surfaces. You might find it a bit too fine for pore filling, although I must say that I've never tried it for that purpose. You could always try it on scrap wood.

It's black like charchol dust so maybe it would stain? I'm not sure.

Oh! Mine is a cream/white colour. Don't know.

My rottonstone makes a gray mess when you use it. I don't think it clears like pumice.

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Waddy

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Sound Clips of most of my guitars

How do you use it for polishing out varnishes?

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We are all in the gutter but some of us are looking at guitars.

I/v only used it (grey rottenstone)to rub out vln oil based varnish. with a cotton rag an mineral oil to get a certain sheen. It gives the vln an antique look depending on what your aiming for.

You can use it with Oil or water. Water being the faster cutting. It will leave scratches but I think it's similar to Pumice in that it breaks down and becomes finer the more you work the surface.
I also have some Tripoli powder which is Pinkish in colour. Even finer than my Rottenstone. My Rottenstone indicates 120 mesh size. Most of the polishing compounds that are sold for varnishes/ cars will have some type of very fine stone/mineral in them. They are just suspended in some type of emulsion or petroleum carrier.
I suppose if you really want super fine you can finish with toothpaste!

Use a bigger tooth brush and less water to reduce sudsing!

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Does it work to polish the world's smallest violin?

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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.

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