Slate with Water vs Slate with Oil?

[mjclark]

What differences can I expect in the finish from using oil rather than water on a slate?
Will oil give a finer result?
Is using lather intermediate between water and oil?
Can I raise a slurry with oil as the medium?

I read somewhere about a particular stone acting like 4k with slurry, 8k with water and 12k with oil and, as a honing novice, this has sparked my interest

 

[Brooksie967]

Lather is an option to use on a stone that is porous and can't handle oil. Oil/Lather adds cushion to the honing process which reduces contact/friction to a certain extent which creates a finer finish.

As far as going from water to lather to oil on a suitable stone... Sounds like a test you should carry out

 

[mjclark]

Lather is an option to use on a stone that is porous and can't handle oil. Oil/Lather adds cushion to the honing process which reduces contact/friction to a certain extent which creates a finer finish.

As far as going from water to lather to oil on a suitable stone... Sounds like a test you should carry out

Thanks for a good clear explanation.
I've got a tired old Sheffield straight coming in the post next week, so I'll try that water-lather-oil progression and let you know how it goes

 

[bluesman 7]

I'm a newbie to all of this, but, isn't using oil on a stone a kind of one way decision? Like, once you've used oil, water will never lie the same on the stone.

 

[Brooksie967]

I'm a newbie to all of this, but, isn't using oil on a stone a kind of one way decision? Like, once you've used oil, water will never lie the same on the stone.

People frequently restore stones that have been oil soaked and as long as you use the right kind of oil it just wipes off ie: smiths honing solution.

 

[PapaFish]

I'm a newbie to all of this, but, isn't using oil on a stone a kind of one way decision? Like, once you've used oil, water will never lie the same on the stone.

That depends on the stone. On a porous stone that has been used with oil for decades, then been left to sit for decades, yes, the oil/residue can be hard to impossible to remove. You can give it a stout cleaning with strong cleaners, but when you wait, oil still comes out of the surface. I have an old Washita stone that no matter how much I use it with mineral oil and scrub it with soap, it still smells like kerosene. It's a great stone, but it's always going to smell like kerosene...

On a non-porous stone, a good scrubbing and lapping should be all it takes. I have never had a non-pourous stone that was used with oil, so I can't say for sure that this will work... but in theory...

If you are worried about the smell sticking around in the stone, just do what I do, use mineral oil. Norton is supposed to have a honing oil that is just highly refined mineral oil. It's food safe and is supposed to do a great job. I am going to seek some out to use on some of my stones.

 

[Alum of Potash]

Some of us like the smell of kerosene, Papa! ;-) Over the summer, while travelling, I played around with a set of small pocket Arkansas stones used with natural jojoba oil. It worked very well, only starting to gum up at the end of my extended visit. To clean it upon my return, I've been thinking to use turpentine. Should have done that before I left. Oh well.

To the OP: I suppose some of it has to do with whether or not you intend to use the slate with a slurry or not. Slurries are normally created with water, and very rarely with oil. I think it has to do with relative viscosity and suspension of particles. Think of it this way, if a slate is porous enough to absorb oil, then it probably shouldn't be used with oil. If it's hard enough to resist oil, then maybe it could be used with oil. I could be wrong here. Preliminary testing should be done with a drop of oil on an out-of-the-way area.

 

[Gamma]

OP - Which slate hone are you talking about? A DT?

 

[mjclark]

OP - Which slate hone are you talking about? A DT?

That mystery possibly-Thuri that I posted about asking for help identifying it.
It doesn't seem porous...

 

[SliceOfLife]

Thuringians were perpetually labeled with warnings not to use them with oil. So if you still think it may be a thuringian, that's something to consider.

 

[Alum of Potash]

That mystery possibly-Thuri that I posted about asking for help identifying it.
It doesn't seem porous...

If that mystery stone turns out to be a "silkstone" in the end, then it probably hales from Wales. Vintage Yellow Lakes and similar dense pieces were used with oil back in the day. Not saying that you should trash a Thuri by any means. Try lapping it with water for starters. Does it seem softer than other slates you have used or harder? If harder, then oil may be in order, given the localized test I mentioned above. If it seems soft, then slurry that thing with water.

 

[mjclark]

If that mystery stone turns out to be a "silkstone" in the end, then it probably hales from Wales. Vintage Yellow Lakes and similar dense pieces were used with oil back in the day. Not saying that you should trash a Thuri by any means. Try lapping it with water for starters. Does it seem softer than other slates you have used or harder? If harder, then oil may be in order, given the localized test I mentioned above. If it seems soft, then slurry that thing with water.

This is the only slate I've yet used, but it seems relatively hard and I thought I'd risk the oil experiment.
I used a 13/16 Ator which previously I'd finished on the slate with just water then CrOx on balsa and got a very nice result.
This time I finished it with the slate+ water/lather/oil progression instead.
I probably needed more time on the oil cos the edge didn't feel as smooth, but it felt much more "powerful", like it had more cutting power so I guess tangibly sharper.
Definitely a success