India Stone Help

[titanxt]

Hello all!!

I purchased a Norton India stone. I noticed that the stone was not very flat, so I tried to flatten it on 100-grit sandpaper. The stone is a "fine" stone, yet 100-grit paper hardly touched it. I do not have a diamond plate, so other than using one of those, how can I flatten it? Also, I noticed that it seemed to clog easily as well, though I was using what I thought was plenty of oil.

Thank you!

Andy

[Axehandle]

India stones require drenching in oil. No less.

[wmickley]

What kind of oil are you using?

[Axehandle]

I think you may need a diamond stone or a crystolon stone. Crystolon stones are silicon carbide which is slightly harder than the aluminum oxide India stone. Or you will need a batch of high quality silicon carbide paper.

India stones are tough and aggressive.

[Rob Young]

titanxt said:

---

Hello all!!

I purchased a Norton India stone. I noticed that the stone was not very flat, so I tried to flatten it on 100-grit sandpaper. The stone is a "fine" stone, yet 100-grit paper hardly touched it. I do not have a diamond plate, so other than using one of those, how can I flatten it? Also, I noticed that it seemed to clog easily as well, though I was using what I thought was plenty of oil.

Thank you!

Andy

---

Hmm, mine was quite flat and I just recently "cleaned" it by rubbing it in big circles on my concrete driveway. Did a decent job.

As to oil, I'm using a 50:50 mix of kerosene and baby oil (mineral oil). So I suppose it smells like truck-driving babies when I sharpen...

With the very thin mix, I don't notice clogging problems. You can soak the stone in kerosene too help clean it if needed.

[Tony Z]

India stones (Norton) are typically quite flat. Flatten (as already posted) on concrete driveway or block or very coarse Sc paper. They are supplied "oil impregnated", but still require oil: Norton suggests their own oil. I use "Marvel Mystery Oil", available at Walmart, for about $3.00 for a quart, that lasts a very long time.

If you're clogging, you're not using enough oil. You need to clean the stone: boiling in water or use an "oven cleaner spray", rinsing then in very hot water, with a stiff brush. Do not put it in SWMBO's dishwasher (works very well, but be prepared for battle).

My sharpening method for years has been coarse Norton 3X on a slow speed grinder, medium india or Washita, then black Arkansas and maybe a bit of stropping (no jigs). Lately I've been using Spyderco's medium, fine and ultra-fine stones. The Spyderco's do require checking for flatness, but they then last a very long time. India stones are pretty hard and need flattening less often.

[Anji12305]

The surface will release built up metal 'swarf' as you clean it.

If using sandpaper, look for the black emery paper version designed for metal work. It will still load up, but it won't do so as quickly.

I recommend a diamond plate for this, and a metal wire brush to clean off the slurry you will generate.

Before boiling, or any other method that applies heat - try the room temperature methods involving finer solvents (like WD40) and lots of towels. Stones like these were maintained in unheated shops for decades, no special cleaning required.

[titanxt]

I was using WD40 liberally applied while using the stone.

The stone was .007" dished in the center and was only making contact on the extreme edges of the stone.

Thank you!

Andy

[Timberwolf]

I use a stationary belt sander with a silicon carbide belt and a foot switch...Lay the stone on the platen and turn the motor on using the foot switch. You can hold it with both hands to keep it flat.

I have snagged quite a few India stones at flea markets and they are usually very hollow.

[titanxt]

How flat are most driveway? I assume the concrete would settle fairly flat. I also would think a bit of touch up would still be needed?

Andy