Flattening Oilstones - No Belt Sander

[Bibliophile 13]

I was sharpening up some blades today, and I just got sick of how out of flat my oilstone had gotten.  To be fair, I've had this thing for probably 8-10 years and have never flattened it.  I kept putting off flattening it because I've got an old belt sander in pieces stored away, and I always figured I'd eventually put the sander back into working order, and then the first thing I'd do would be to flatten my oilstones.  Today I realized that just wasn't going to happen.  

More out of frustration than anything, I grabbed a roll of coarse Klingspor sandpaper I had lying around.  I secured one end of a long strip (maybe 3' long) to my workbench top with a holdfast.  



Then I went to work.  I just put as much even pressure on the stone as I could as I slid it one way down the sandpaper.  Every couple strokes, I'd turn the stone around.  



Yeah, it really needed flattening.  The white around the edges is the high spots.  The grey spot in the middle is the low spot.  This is after maybe 5 minutes of work.  



And this is after about 10 minutes of work.  I had to clean the sandpaper off several times.  If I had had a vacuum handy I would have used that.  Instead, I just took it outside and brushed it off with a stiff brush.  I guess I could have just changed out the sandpaper when it loaded up, but (a) I'm a cheapskate, and (b) I didn't feel like digging out another roll.  



A little bit of oil brings out the color variations. 

I'm sure it's not quite as flat as some high-quality industrial equipment could make it, but it's MUCH flatter than it was before, and that's what matters to me.  Sharpening is going to less of a hassle now.  

If I had known how quick and easy this was going to be, I wouldn't have put it off so long!  I might just make this a routine annual maintenance job.

Oh yeah, and this is also totally a plug for the Klingspor bargain box of end rolls.

[jstraw]

Great post. Another option is a floor sander belt from your local rental store. I have used them for years to flatten plane soles.

I picked up a very old black Arkansas stone on the cheap that needs flattening.

[Scoony]

I keep a cheap Smiths corse diamond stone near my oil stones to dress them up and keep them flat. It is flat enough for oil stones and has lasted a few years now.

Biggest problem I have with the stones, is the oil building up on the sides and bottom of the stone. They get pretty grungy. I soak them in mineral spirits and clean them up everyone in a while. Now I am thinking of trying some sort of metal fabric/screen under the stones to allow the oil and grime to drain away.

[bandit571]

use to be able to clean some stones, using just Kerosene...

[Tony Z]

Vintage stones (that I may want to use), I clean with a soak of oven cleaner, let sit in the sun, then rinse in very hot water. Wiping your stones with a cloth after each use, helps keep them clean. Flattening? If you think that helps, have at it, but most hard arkansas and transluscents are already plenty flat. Learn to sharpen free hand and use the entire stone.

Oilstones that need flattening are generally manmade "carborundum" stones, and when you come across used oilstones that are pretty dished, chances are they're manmade.

[Scoony]

Vintage stones (that I may want to use), I clean with a soak of oven cleaner, let sit in the sun, then rinse in very hot water.  Wiping your stones with a cloth after each use, helps keep them clean.  Flattening?  If you think that helps, have at it, but most hard arkansas and transluscents are already plenty flat.  Learn to sharpen free hand and use the entire stone.

Oilstones that need flattening are generally manmade "carborundum" stones, and when you come across used oilstones that are pretty dished, chances are they're manmade.

Natural stones will dish out. Seen some naturals that were very dished out.

[Tony Z]

Natural stones will dish out. Seen some naturals that were very dished out.

What type of natural stone? Chances are they were not hard black or translucent Arkansas stones that I was referring to. I would suspect that in days of yore, the professional craftsmen did their sharpening freehand, and used pretty much the entire stone.

[Timberwolf]

What type of natural stone?  Chances are they were not hard black or translucent Arkansas stones that I was referring to.  I would suspect that in days of yore, the professional craftsmen did their sharpening freehand, and used pretty much the entire stone.

.........................
How they wear depends on the matrix as Tony suggests in his comments..The matrix containing the abrasive in Novaculite stones such as Arkies and Washitas can vary greatly..I have a hard, translucent Arkie that cuts much faster than some of it's cousins that I own and it is usually my last "go to" stone before the strop. It shows zero wear..and is as flat as the day it was cut. Their abrasive qualities can vary from other hones mined just two feet away. So if you get one that you like, treasure it. It should last your lifetime!

IME tho, most carpenters in the olden days used Carborundum hones...I say that because of all I have seen {and purchased} at the many years I spent perusing flea markets and tool meets. I once sold a Norton Belgian Coticule in the original box for 200 bucks on Ebay..I paid a fellow "tool guy" ten bucks for it at a tool meet and Hank was there!.
..It dated back to the late 1800's...It pays to "know your stones"...Right, Tony???

[Tony Z]

.........................
How they wear depends on the matrix as Tony suggests in his comments..The matrix containing the abrasive in Novaculite stones such as Arkies and Washitas can vary greatly..I have a hard, translucent Arkie that cuts much faster than some of it's cousins that I own and it is usually my last "go to" stone before the strop. It shows zero wear..and is as flat as the day it was cut. Their abrasive qualities can vary from other hones mined just two feet away. So if you get one that you like, treasure it. It should last your lifetime!

IME tho, most carpenters in the olden days used Carborundum hones...I say that because of all I have seen {and purchased} at the many years I spent perusing flea markets and tool meets. I once sold a Norton Belgian Coticule in the original box for 200 bucks on Ebay..I paid a fellow "tool guy" ten bucks for it at a tool meet and Hank was there!.
..It dated back to the late 1800's...It pays to "know your stones"...Right, Tony???
 

Yep! Little clue to stones, that I've mentioned (besides the fingernail scratch test for fineness), is if the former owner took enough pride (besides the initial cost) in his tools to carve out a fancy box for it.

Jack's right about carpenters using mainly Carborundum stones, and they dish rapidly. India stones (also man made) last pretty well, except for the coarse ones, that will eventually dish.

[bandit571]

Found these a few years back...
[attachment=20195]
Still have them in the shop.....they are to be cleaned with kerosene....according to the box.