Norton 'Economy' Stone: feedback from manufacturer re: abrasive type

[Obsessed with Edges]

The rubbing stones make a good base and they're pretty flat as well, but for serious lapping I've found failure to include a loose grit to result in some stone glazing, no matter how much water is used. Even a pinch or two of blasting grit will work wonders compared to the bare stone. Have heard the Simple Green works well too, and I used to use soapy water, but after trying oil for a while, I can't bring myself to use another method unless I have no choice. Other options work, or nothing at all if I'm camping or on the go or in a real hurry. The oil seems to keep the stone in the best shape and in my hands the best edge per grit value. Have heard the oil promotes breakdown of the binder faster than other choices, don't know if this is true but my stones all look brand new after much use - actually better than brand new. Keep your observations coming, I'm very interested.

HH

Just an idea, I have some emery cloth that might provide the loose grit. Also have a granite 'reference plate' (dead flat), bought at a Woodcraft store a few years ago, which could serve as the base for it. The emery grit comes off the cloth backing almost immediately after it's wetted, and I've often thought that could be useful for some 'instant lapping slurry' if/when needed. Might fiddle with that a bit. Might also put down a full sheet of wet/dry SiC sandpaper, under the emery cloth, to protect the granite's surface. The 'emery' should be corundum (natural aluminum oxide), which is very hard stuff at ~9 on the Moh's scale. Not sure if it's hard enough to abrade the SiC of the stone, but might serve to dislodge it from the binder, which would be ideal I'd think, for flattening (if it works).

I used the Fine side of the stone again this afternoon, to re-bevel the spey blade on a Case trapper (420HC). I actually soaked the stone in the sink (water), then spritzed it with a little Simple Green for the grinding. After a minute or two of that, when checking the edge of the blade, I just put the stone back into the sink of water, and then re-spritzed with the SG for the next bit of grinding. That seemed to work pretty well, and I'm not seeing any indication of the stone getting loaded at all (and did see a lot of the leftover swarf & such in the bottom of the sink, afterwards). I did do a little rubbing with the fingertip, while immersing the stone, to lightly rinse away whatever might be collecting on it. Officially, it 'needs more study' , but so far, so good. I do like the aggressiveness of the SiC in this stone. Even the 'Fine' side works very quickly, it seems, at least on the relatively simple stainless I've tried so far.


David

 

[David Martin]

Yes, the emery grit comes off the wet/dry paper quick after wetting. I've captured some of this grit and retained it for slurry on a strop but have yet to use it. So, I wish you'd go ahead and use some then let me know how it works. Agreed the fine SiC side stone works quickly on 420HC steel. Less quickly on some of the tougher steels like 440C but it still works well enough. DM

 

[HeavyHanded]

Just an idea, I have some emery cloth that might provide the loose grit. Also have a granite 'reference plate' (dead flat), bought at a Woodcraft store a few years ago, which could serve as the base for it. The emery grit comes off the cloth backing almost immediately after it's wetted, and I've often thought that could be useful for some 'instant lapping slurry' if/when needed. Might fiddle with that a bit. Might also put down a full sheet of wet/dry SiC sandpaper, under the emery cloth, to protect the granite's surface. The 'emery' should be corundum (natural aluminum oxide), which is very hard stuff at ~9 on the Moh's scale. Not sure if it's hard enough to abrade the SiC of the stone, but might serve to dislodge it from the binder, which would be ideal I'd think, for flattening (if it works).

I used the Fine side of the stone again this afternoon, to re-bevel the spey blade on a Case trapper (420HC). I actually soaked the stone in the sink (water), then spritzed it with a little Simple Green for the grinding. After a minute or two of that, when checking the edge of the blade, I just put the stone back into the sink of water, and then re-spritzed with the SG for the next bit of grinding. That seemed to work pretty well, and I'm not seeing any indication of the stone getting loaded at all (and did see a lot of the leftover swarf & such in the bottom of the sink, afterwards). I did do a little rubbing with the fingertip, while immersing the stone, to lightly rinse away whatever might be collecting on it. Officially, it 'needs more study' , but so far, so good. I do like the aggressiveness of the SiC in this stone. Even the 'Fine' side works very quickly, it seems, at least on the relatively simple stainless I've tried so far.


David

This my working theory, that the loose grit, even if its just natural silica for the most part, will dislodge or fracture the SiC even if its not hard enough to out-grind it. Its not like lapping an Arkansas stone or Spyderco ceramic. Though I have to admit I'm spoiled by having a number of SiC powders at hand.

I know from experience of sharpening a number of machetes on my India stone that much of the grit will be prevented from lodging by use of water-based lubes. I just keep a bucket of very soapy water handy and give it a dunk every so often. This is not the most convenient method but it works and keeps the stone from clogging. Oil will float the swarf right off the surface as you work, no need to rinse. From my POV I used to periodically lap my manufactured ALumOx and SiC stones to keep the surface at its best and have since discontinued doing so after switching to oil. I clearly have a bias here, and my short-pass method of grinding keeps most of the oil from sluicing right off the side of the stone as well, so a bunch of factors all lining up to make it a better choice for me - not to mention it helps keep my finger tips from splitting in the colder months. Whatever works best - its all good.

 

[David Martin]

Yes, I think using oil helps keep stone wear down to a minimum. Plus, once I started using mineral oil I too have noticed my hands have fewer cold cracks. DM

 

[Obsessed with Edges]

Thanks HH and David. I like the 'sounding board' we have here on the forum; it's a great place to throw some thoughts around and consider other perspectives given in feedback. Your input gives me some things to think about. I may still come around to oiling this stone. It'll be easier, initially, to try these other ideas before the oil, so I won't have worry about 'un-oiling' it later. Nice thing about this stone, it's not so expensive as to make me shy about experimenting with a few things, which is usually pretty fun & enlightening.

Thanks again. :thumbup:

BTW, David, I can relate to the cracked hands. Being a lifelong NM resident, skin can get insanely dry at times, especially in the winter. I've always kept some mineral oil-based hand lotion nearby, and it's about as good as anything I've used to remedy my fingertips and knuckles, when they start cracking. I've actually used it on my diamond hones too (all in the quest for knowledge ). I like the feedback from the hones when I use it, and it does a nice job in keeping the swarf from really sticking to them. It's viscous enough that it doesn't make a drippy mess, which is especially handy when used on a hand-held pocket hone (doesn't run off). And it doesn't hurt that it keeps my fingertips supple as well, while working.


David