Re: agree

Re: agree

John in New Mexico

I had no idea that Norton crystolons weren't long wearing. I must have a hard one, been using it for years with no sign of wear. I do recall that lighter color carborundum stones used as medium grit knife slips tend to hollow, but I've never had one of those as a shop stone (the crystolon I have is coarse and dark grey).

Its all just silicon carbide, the difference is likely in the bond between grains. On grinding wheels there's a whole system describing bond strength, probably it applies to bench stones but no one mentions it. The carborundum stones that wear are likely designed to do so, friable stones cut more aggressively for their grit size (or more accurately they seem to do so) because fresh grit is exposed continually by use. Perhaps finer grit crystolons are friable whereas coarse ones are not?

Re: agree

Jack Dover

I presume you're about to open a door to a wonderful world of jade and agate stones too? They're quite fun stones, not essential by any means, but quite useful. There's also this artificial pink stone referred to as a "artificial ruby". That's a good one, I've bought a full sized one, event though it felt a bit too expensive — it costs about as much as a Spyderco ceramic stone. It probably wasn't meant for woodworking, it's just I liked a small (very, very small) pink stone so much that couldn't resist getting a full sized.

I don't remember exactly (let me put it this way) how Carborundum stones made into my shop, but I like goofing around with stones. SiCa stones were around as long as I remember myself, never considered any of these as a viable sharpening stone for any sort of a refined edge. One day I've noticed they're different quality and have different properties, so I picked two or three stones just to experiment. One small stone had a box that said something like "original carborundum" and "Niagara", it was good, so I bough a regular 8x2 stone. They're everywhere, it's just eBay shipping brings them to the price range of Nortons.

There's also some no brand name stones that look and feel very identical to Nortons, but they're in 10$ price range. When inquired a vendor proudly claimed that "these are NOT Nortons guaranteed - they are made in USA!". So far I got a combo SiCa and a combo that looks like India. They work quite okay - hard, aggressive enough, not too scratchy. Can't tell whether all of them are like this or I just managed to pull a good one randomly.

Re: agree

Jack Dover

I have a 3x8" Norton Crystolon (not combo) and it dishes like crazy, almost as fast as a waterstone if not faster. Maybe their Pike brand is harder wearing, but this one sheds crystals everywhere and contaminates everything around. It's a very aggressive stone, which is, I think, due to a weak bonding agent as you've mentioned. And apparently there are tons of variants of their Crystolons, so now I wonder whether all of them use the same agent.

I agree that the bonding is what makes a difference. Smith's tri-hone system carries two carborundum stones. Not sure what were they using, but my dry saliva has better bonding properties. Yet these two stones are FAST, what's interesting - their medium stone is faster than a coarse stone. Of course it's all nullified by the fact they are always dished and I wore them down with a flattening stone in about 6 months. My guess is that aggressiveness is all due to a weak bonding. What's even worse - hardness is not even. There are hard spots that almost don't wear and there are soft spots that turn into jello-like consistency. It's a shame, really, I like the sharpener. Btw, if anybody has built a triangular type holder - I'd be interested to have a look at the construction, don't feel like splurging on IM313 just yet.

The other thing about my stone is that it doesn't grade over. Coarse India and other carborundum stones loose a bit of aggressiveness for less scratches. This one doesn't, also I can't find any workable honing fluid for it, everything soaks like water in hot sand. When I was young, people that were into knives were looking for softer SiCa stones, but they were used pretty much like a water stone: in a water pond such that it could be dunked easily. Idk, maybe this stone isn't for woodworking?

Re: agree

John in New Mexico

The Pike brand is the one I have. Its hard and thin. Might not cut as quick as you're used to, but it stays flat. I find it to be a good starting point for honing, fairly aggressive and can be followed with an arkansas I have that cuts about like 600 grit SiC paper. Then buff.

Re: agree

Jack Dover

Yeah, double checked, mine is different. I have this one: https://www.nortonabrasives.com/en-us/product/crystolon-sc-single-grit-benchstone with a model no 61463654459. It comes in a plastic box like their water stones with a generic Norton branding. Pike comes in a cardboard box with a tiger head. They look different even on a photo, yours is darker color, mine is mouse gray.

Does your soak oil instantly?

Re: agree

John in New Mexico

Not really instantly, but when it was new it soaked up light oil (WD-40) quicker than did the coarse Arkansas stone.

These days it's oily enough that I don't always add oil if its just going to be a couple swipes.