Thread: Degreasing an old stone.

Howdy all,
My apartment manager gave me some old hones from the toolshed and one of them looks very promising. No box, no label. It's extremely fine, and just might make a decent finishing hone. The problem is that it had a very heavy coating of grease and dust from years of disuse. I had hoped to able to degrease it and use it with water but so far that hasn't happened. I soaked it for a week in strong 409 cleaner, then a few days in plain water, then another week in 409. It feels totally ungreasy but water just beads up on it like it was wax. Does anyone know a process or solvent for getting the old grease and oil out? I may have to just decide to use it with oil after all but I'd prefer not to.

I got oil off a vintage Thuri pretty good by soaking it in a bucket of water with oxiclean and dishwashing soap.

Followed by a good lapping seemed to do the trick.

all dirty stuff you can use brake fluid cleaner and clean up then move to next step.
put stone inside salt box for a week . then check see what you left.
oven cleaner works too.gl

Depends how deep the oil penetrated. Most degreasers should work if its near the surface. If it's deeper you could try something that can draw the oil out. Maybe some of that stuff they use in garages to absorb oil or kaolin-clay might work too.

Howard from The Perfect Edge recommended oven cleaner. Easy Off with the blue label IIRC. Less fumes with the blue label. Haven't tried it myself.

Washing Soda is often used, but may not be any more effective than your 409 cleaner - both are very alkaline. . A strong mix of bio washing machine detergent in very hot water used as a prolonged soak often works, too.

A stronger alkali would be caustic soda (lye or drain cleaner) but you should read-up on its use and hazards before using it - it generates heat when dissolved in water and can cause severe burns if you aren't careful.

Industrial degreasers are another option. The older ones were quite hazardous (trike, etc) but modern ones are 'greener' and safer to use.

You could go the solvent route - soak the stone in a volatile solvent like alchol or industrial methylated spirit (the clear type, not the blue one) in a closed, non-reactive container. Dispose of liquid when saturated and add fresh stuff, slightly diluted with water. Repeat, adding slightly more water each time. When you reach the 50/50 mark whatever is left should be soluble in a strong detergent mixture.

Or - you could add dish-washing detergent to the honing water - that will allow it to spread out on the surface of the hone - a quicker and cheaper solution than the above!

Regards,
Neil

use oxiclean scrub the stone get an old pot and towel or large rag put the rag in the bottom of the pot and then the stone turn the heat on put some oxiclean in the pot get the water hot until it steams but not a boil the stone should be sitting on the rag it will protect the stone from the heat on the bottom of the pan the oil should float to the top of the water

Originally Posted by JimmyHAD

Howard from The Perfect Edge recommended oven cleaner. Easy Off with the blue label IIRC. Less fumes with the blue label. Haven't tried it myself.

+1 on Easy Off. I used the old fashioned fuming version (outside in a good breeze and with kitchen gloves and goggles!) on some incredibly gunky hones from an eBay lot. Let it soak for half an hour and hosed the stones down. That got most of the grunge off them and revealed a coticule among the lot that was unrecognizable prior to cleaning. The rest of the staining had to be lapped off on a DMT-a good arm and shoulder workout! Good luck and hope you have a nice hone under the crud.

Here is my suggestion for cleaning that old stone.

Find something to soak it in, preferably something that fits fairly close around the sides. A small, squared off tub would be best, but a glass jar will also work if large enough. My own best choice would be something like a glass bread loaf pan.

Put in the stone, maybe resting it on a couple of tooth picks or something to give some space under it.

Now pour in either naptha or laquer thinner until the stone is covered. Cover the pan to prevent evaporation.

Let the the stone sit in the thinner for a week. Then drain and repeat using fresh thinner as required.

The laquer thinner should leech out that old oil fairly well.

Naturally, after the final soaking you are going to have to let the stone sit and air out before you take it into the house for use.

Note: You do not want to do this in the house and you will want to be certain that this is done in an area where there is no source of ignition which might set off any fumes that escape from the tub.

Maybe a local machine shop will give or sell you a quart or so of water-based cutting fluid; many use a lot of it and it is rather inexpensive. It is an emulsified solution that should pull some oil out of your hone by "binding" with it. Just soak the hone in it overnight and slosh it around several times.

I also think that all the oil can not be removed. If it's an oilstone, I would just continue to use oil with it.