Coarse (and durable) medium for blade sharpening?

[Peter Daniels]

Fall always has me in the shop more.
And that has me sharpening more.

I’ve had a hell of a time sharpening a Veritas plane blade (PMV-11) over the years.
If I ever need to re-establish the primary bevel-it’s a long process full of frustration.
I’ve tried a coarse diamond stone.
A very coarse sharpening stone.
Various sand paper style sheets.

All do ok for a bit. And then seem to dull or become smooth making the process extra slow.

The diamond stone doesn’t seem as coarse as it once was.
The stones eventually develop a cup.
And the paper works for a short bit but also becomes less abrasive.

Do you have any suggestions for a durable material I can use for those initial steps when I’m needing to remove material and not just touch up an already perfect edge?

Thanks.
PD

[Tony Wilkins]

Have you thought about a bench grinder?

[Rob Luter]

I use a slow speed bench grinder for big jobs, but as far as stones go, I use a Trend 300/1000 Diamond Bench Stone. It makes short work of tough steel.

[Jim Koepke]

There are only a couple of PMv-11 blades in my shop. I may have put them up against my water stones, can't recall. For sure they have been honed on a Washita, Hard Arkansas, a Black Arkansas or a Translucent Arkansas.

Mostly these days my water stones only get used on A2 or occasionally when trying something different.

jtk

[Richard Hutchings]

Don't wear your self and your stones out like tha5. It's perfectly OK to use a high speed grinder if that's all you have. It's what I use. Just make sure to dunk it in water every so often. The concave grind takes all the work out of sharpening on the stones later on.

[George Yetka]

Ive not had to re-establish bevels on my pmv11 stuff. I did it once and have been luck enough for the past 8 years to just start at 1000/3000 and sharpen to 10k. I have a DMT Diaflat that I use to keep stones flat and that would be where I would go to reestablish if I had to. I may even pick up a dedicated 300 stone if it were needed, Though I dont use hand tools every day.

[Tom M King]

If you absolutely don't want to use a bench grinder:

https://sawmillcreek.org/showthread....rpening-stones

[Rafael Herrera]

Nowadays I tend to use the bench grinder to establish the primary bevel, shallower than the ultimate cutting bevel so that I only sharpen a narrow strip at the tip. I'm not that obsessive about this primary bevel, it does not look pretty or flat. Some people feel uncomfortable with this look and want a uniform and a specific bevel angle. For this, a simple method is to use PSA (pressure sensitive adhesive) 80 grit sandpaper, a flat substrate, blue tape, and a honing guide. Cover the substrate with the blue tape, place the sandpaper on top of it and then go to town on the iron. The reason for the blue tape is that it makes it very easy to replace the sandpaper. After a few passes the iron can get very hot, so you may want to wear gloves and have some water available to cool it.

What I wrote above is not a sharpening method, it's meant for quickly removing the metal to form the bevel. Something that is done infrequently.

That's what it sounds like what you're after, since you're asking about coarse media. However, you may be sharpening using a single bevel, you didn't say. That makes the sharpening process tedious and slow, since you're working on the whole bevel every time, regardless of the media.

If using the shallow primary bevel style, I would use a medium diamond stone followed by a fine stone.

Rafael

[Reed Gray]

I use a platform on a slow speed grinder with CBN wheels to set my primary bevel. I have not had any problems, and that includes some antique blades that were very rounded over. Main thing is to pay attention to heating the blade. Another alternative would be the Tormek and the diamond stones. If the primary bevel is really bad, you can use 80 or so grit of the abrasive belts that are made for metal. Again, care must be taken to avoid overheating the metal so that it loses the temper. Once I have my primary bevel established, I take it to diamond stones, 120 grit and up.

robo hippy

[Jimmy Harris]

Sharpening stones are for sharpening. Bench grinders are for grinding bevels. You can grind a bevel with a sharpening stone, I've definitely done it before, but it takes forever and wears out your stone. Oustside of a bench grinder, maybe your best bet is something like a belt sander or file? Cutting steel is hard and it's gonna eat up whatever you use to sharpen it. So don't use something expensive. Bench grinders are pretty cheap, and I'd rather buy a cheap grinder for occasional use than waste a good file, good stone, or lots of sanding belts.

[Prashun Patel]

A bench grinder with CBN wheel (180 grit or 80 grit are fine for this purpose) are really nice to have. The CBN is expensive but runs truer and lasts longer than a typical friable wheel.

A bench grinder will be much faster than stones for primary bevel setting. It makes a hollow grind, which can assist with freehand sharpening of the secondary bevel on the stones.

[Richard Coers]

Don't wear your self and your stones out like tha5. It's perfectly OK to use a high speed grinder if that's all you have. It's what I use. Just make sure to dunk it in water every so often. The concave grind takes all the work out of sharpening on the stones later on.

I thought dunking in water was verboten? If the hard steel is too hot you can induce some micro cracking.

[Tony Wilkins]

I thought dunking in water was verboten? If the hard steel is too hot you can induce some micro cracking.

It won’t hurt if you do it often and before you get the steel too hot.

[Richard Hutchings]

What he said

[John C Cox]

I love my worksharp for exactly this sort of duty. 80-grit Diablo PSA discs (available via BORG) make quick work of chips and dings. Once you are up to P400 or so, move back to the stones.

There are several very fast coarse stones out there. Unfortunately, they tend to be quite friable and require regular flattening. Regular old Norton India stones work nicely once you flatten/refresh them, but they're still a lot slower than power.... Gice me power for grinding any day. I save my stones for final honing.