Thread: Arkansas hardness

I have seen that natural japanese water stones are rated with a hardness number such as Lv2, Lv3, Lv 4 and Lv5. If we could rate a Translucent or a Black Arkansas, how hard could they be rated with this same scale? Thank you.

Eleven.

And yes, here it is again...



Joking aside, I do think hard Arks are harder than hard Japanese hones.

Problem with an ark is it's reliant on the burnish.

Once you start to put slurry on them you have to be careful, If you go too low the burnish will just vanish and you have to start again.

I've played with mine with slurry, and outside of the finest finishing slurries you have to pay attention. I've had some success with light coti and thuri slurries provided I build the slurry on a DTM and transfer it over. If I try to slurry on the rock my burnish generally doesn't fare so well. I once tried a 6K king slurry and the stone came off looking shot blasted.

I have a collection of stones, diamond, Japanese, Arkansas and Lapping film. I really love the lapping film for the very last finish. I prefer the Arkansas because they are less hassel than Japanese water stones. The have to soak so long. I have up to 15,000grit but the Arkansas I have soft, black and translucent. They do take a lot of work, slow and even control. I like the 3 inch because it covers most blades. Diamond I am not too fansey for as they seem to take of more than I want I have been doing this for 20 years and am still learning. Best Sharpening stores carry the lapping film. One sheet will cut three pieces and mounted on a flat, smooth surface it will service about 30 razors before having to change. if you have not tried them I would suggest that you give them a go. Be extra careful because you can cut them very easy.

LV-5+++ UP UP UP

I have some pretty hard LV-5 jnats and none of them compare to the vintage Trans and blacks I've lapped.

Originally Posted by Dcaddo1

LV-5+++ UP UP UP

I have some pretty hard LV-5 jnats and none of them compare to the vintage Trans and blacks I've lapped.

^ This

LV-6

Thanks everybody. I'll try raising some slurry on a translucent, to see what I get.

Originally Posted by Glock27

I prefer the Arkansas because they are less hassel than Japanese water stones. The have to soak so long. I have up to 15,000grit but the Arkansas I have soft, black and translucent.

Japanese natural water stones, about which the OP asked, do not need to be soaked at all.

Originally Posted by Iceni

Problem with an ark is it's reliant on the burnish.

Once you start to put slurry on them you have to be careful, If you go too low the burnish will just vanish and you have to start again.

I've played with mine with slurry, and outside of the finest finishing slurries you have to pay attention. I've had some success with light coti and thuri slurries provided I build the slurry on a DTM and transfer it over. If I try to slurry on the rock my burnish generally doesn't fare so well. I once tried a 6K king slurry and the stone came off looking shot blasted.

Originally Posted by jelajemi

Thanks everybody. I'll try raising some slurry on a translucent, to see what I get.

For the reason Iceni gave, slurrying an Arkansas stone is not a great idea. If you do decide to experiment with it, realize you may have some work ahead of you to restore the surface of the Ark.

The translucent Arks are as hard as quartzite, means the hardness is in a region of 7 according to the Mohs scale. For comparison Carborundum has a Mohs hardness of 9, diamond 10. The scale used with Jnats is not the Mohs scale, it is just a scale from soft to hard (1-5) if I recall correct. Don't know if it is somehow based on one of the scientific scales. But I have lappped several Jnats up to a lv5 and would rate them somehow according to Mohs with the number, considering that Thuringians are around Mohs 3.