# Abrasive grit trials



## kweinert (Oct 26, 2017)

So, since Yorkshire Grit worked so well I thought I'd try to 'duplicate' it.

Batch #1: not a complete success

Parts by weight:
Mineral Oil: 5
Beeswax: 1
Pumice: 1
Rottenstone: 1/2
Damar Resin: 1/2

The logic for twice as much pumice as rottenstone was that the larger particles will break down into smaller ones. The logic for the Damar resin was to stiffen the mixture a bit.

That's the part that failed because in spite of what I read I didn't see any hard numbers and didn't realize that the resin wouldn't dissolve until a much higher temperate was reached. Since I was warming the mix in a double boiler the resin got sticky but it was never going to dissolve into the mixture. I would have had to mix it in direct heat for the resin to dissolve.

Batch #2:

Parts by weight:
Same as batch #1 except that the resin was replaced by Carnuba wax.

This one may work. At least it has the texture I'm looking for. I'll turn some test pieces and use it, see how it works out on the lathe.

A couple of tips if you want to try this:

Use a disposable container, at least for mixing. I'm using some of those ziploc disposable tupperware types of containers. At the moment both for mixing and for storing. I mix in a 42 oz container and store in a 4 oz (the 4 oz works because I used 1 oz as the measurements for these trials.)

Ensure your Carnuba isn't clumpy. The second batch had a couple of small chunks of Carnuba that didn't melt. The unclumped flakes melted without any issues.

If this works out on the lathe then I'll post this 'recipe' over in the correct forum but I didn't want to put it there until I had tried it out first. You never know what tweaks might still need to be made before I'm satisfied.

Reactions: Like 1 | Way Cool 2


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## Lou Currier (Oct 26, 2017)




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## kweinert (Oct 26, 2017)

After a first quick trial on a piece of plum from my parent's house I can give three initial thoughts:

1. Batch #1 is confirmed as way too loose.
2. Batch #2 is actually a bit too firm
3. I feel like I need to add more grit to the mix.

The result isn't quite as nice as the YG is. If you've ever used that you can hear the grit working. I did get that sound with mine but it didn't last nearly as long and I don't feel that the finish was quite as nice as with YG.

Steps in the right direction, more fine tuning needed.

I will say this if you try this sort of thing yourself, either for an abrasive grit or a wax finish - carnuba wax will make your mix firm very quickly. I have some earlier experiments in finish making that are carveable they're so hard which is a result of too much CW. Those were made with mineral spirits so remelting only makes it worse. But that's an entirely different set of tests for a different thread on a different day.

Reactions: Informative 1


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## Schroedc (Oct 26, 2017)

Maybe try beeswax?


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## kweinert (Oct 26, 2017)

It has beeswax in it. I either need to reduce the amount of oil or use a stiffer wax in it. The carnuba just works too well so I need less of it. 

In this mix it's not terribly stiff, just not as smooth as I'd like it to be. 

Maybe another 1/2 measure of beeswax would be sufficient. Maybe more of the grit I'll be adding contributes to the stiffness.

Reactions: Like 1


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## Karl_TN (Oct 27, 2017)

@kweinert 

Sounds like you are trying to make something like Yorkshire Grit and Hampshire Sheen in the same prooduct by adding harder wax like carnuba. Consider making two products and leaving the harder waxes for the sheen part. Really hope you find a formula that works. I have some rotten stone from an estate that I could try, but don't recall getting any pumice. What pumice do you suggest using?

Related topic: Yorkshire grit says it's "an abrasive paste formulated to give a fine keyed surface to your turnings, *prior* to applying your finish of choice. It consists of pharmaceutical grade ingredients, including mineral oil, beeswax and ultra fine grinding powders.". If YG contains both wax & mineral oil then how can they say apply the finish of your choice? Seems like you'd be stuck with a wax based finish like Hampshire Sheen which contains a blended mix of danish oil, carnuaba and microcrystalline waxes.


-Karl


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## kweinert (Oct 27, 2017)

Karl_TN said:


> @kweinert
> 
> Sounds like you are trying to make something like Yorkshire Grit and Hampshire Sheen in the same prooduct by adding harder wax like carnuba. Consider making two products and leaving the harder waxes for the sheen part. Really hope you find a formula that works. I have some rotten stone from an estate that I could try, but don't recall getting any pumice. What pumice do you suggest using?
> 
> -Karl



Maybe, but not really.

My thought was a way to control the stiffness of the paste. Perhaps that's better done by varying the mix of oil and wax.

A for the pumice I got mine from Amazon and it's from Behlen.


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## Lou Currier (Oct 27, 2017)




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## Mike Mills (Oct 31, 2017)

I just saw this thread and have a few questions (devil's advocate).
In youtube videos this is used after sanding to 220 or 360. Since it is removed prior to finishing does it act like a pore filler? Are there are problems with some woods, like walnut, having muddy areas where light and dark meet?
I still have pumice and rottenstone from many years back. Have you tried either just sprinkled on a cloth damp with paraffin oil?
I realize it cuts down on sanding dust. Are there other benefits?


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## kweinert (Oct 31, 2017)

I haven't seen it act as a pore filler at all. With the commercial product (Yorkshire Grit) I only sanded to 220 on wood (on acrylics I dry sanded to 220, then wet sanded to 600). With my mixture so far I did have to dry sand to 320 first (I've only tried it on wood so far.) When I only sanded to 220 I could still see scratch marks in the surface. At 320 I can still see them (which is why I'm still working on my final mixture) but my wife doesn't see them and thinks I'm being too picky.

I've not seen an issue with walnut but I don't yet have extensive experience with it.

I have not tried using the abrasive directly with paraffin oil.

The advantage that I see is that you don't have to sand as fine with 'regular' sand paper. Not only does it cut down on the dust but as you work it on the surface the particles break down and provide a finer grit. I don't think, in the long run, that the final result is better than sanding through the grits but it does seem to provide a faster result with less dust.

Reactions: Like 1


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## Mike Mills (Oct 31, 2017)

I wait on the results of your next batch. The folks I have seen on youtube really like the Yorkshire grit.
I have only used pumice and rottenstone on finished items (finishing the finish). 
I think mineral oil and paraffin oil are about the same thing... maybe one is refined more since it can be taken internal?


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## Tom Smart (Nov 2, 2017)

Ken, I wasn't looking for it, but coincidently found this video on making abrasive paste.


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