Oilstone, oldies

[biskit]

What do you do with your old oilstones. I have a few old misshaped ones and don't want to throw them out if there is a use I could put them too. :?

 

[Cheshirechappie]

That's rather a broad question - it depends on the oilstones in question. Some, especially the older natural ones, are quite sought after. Finer-grained ones, such as translucent Arkansas and Snowdon Greenstone, are also prized, up to a point. Nice wooden cases add to desirability and value. Small, rough-grained man-made stones, especially if badly worn, are not worth much.

It's possible to flatten oilstones. A coarse diamond plate would work if you have one (rather a spendy solution if you haven't). Charles Hayward suggested dressing a piece of hardwood with automotive valve-grinding paste (I've not tried this, so don't blame me if it takes weeks!). The old method is to use sharp sand and water on a flat stone - and that would be a slow job!

I suppose it would be possible to cut and dress old stones into slips, but given that oilstone slips are fairly readily available and don't cost the earth, it's almost certainly not worth the bother.

 

[Jacob]

Freshen them up with a 3M diapad or similar (plus white spirit) i.e. something flexible so it follows the profile.
Then use them. If useless bin or ebay.
They don't need flattening - unless you are intent on struggling with a jig, which won't work on a less than flat surface.

 

[lurker]

I have flattened them on a concrete slab in my path. Scrubbing brush and paraffin shifts the embedded gunk

 

[bugbear]

What do you do with your old oilstones. I have a few old misshaped ones and don't want to throw them out if there is a use I could put them too. :?

In the old days it was usual not to bother removing material to make quarried oilstones
rectilinear - only the upper surface was flattened, not the sides or bottom.

To anyone used to modern "8x2x1" stones these are a little disconcerting, but they work fine.

This one is a nice Arkansas, and is my usual finishing stone.

BugBear

 

[Rorschach]

I flatten my waterstone on my 12" disc sander.

 

[ED65]

I have a few old misshaped ones

Misshapen in what ways? If it's just that the faces aren't flat that can be rectified on a concrete block, using 80 grit aluminium oxide paper, a coarse diamond plate and other methods. Remember though this is only if you want to, concave stones can be used as they are for directly forming convex bevels if you're inclined that way. Obviously you do need at least one stone that's flat for removing the burr from the back.

If you do want to flatten, fair warning: it can take some elbow grease! Good stones are dense and hard and if they're very out of flat there's a lot of material to take off so don't be discouraged if after 10 minutes hard graft they're not there yet.