The thread on the barkwindjammer sharpening is long and this is a bit of a topic change so I thought I'd start a different thread. First a couple quotes that spawned this post:
It doesn't take any more effort. In fact, it takes less effort. If one takes care of their sharpening stones and tools, things get pretty easy. If you keep the stones flat and the faces of the tools flat, each sharpening is actually doing the prep work for subsequent sharpening. Abrasives are actually a collection of tiny cutting edges and, like all cutting edges, they get dull. Water stones and white or pink grinding wheels are more friable than oil stones or normal grinding stones so the expose fresh abrasive on their own. The problem with this is that the friable abrasives lose their shape quickly and it's very difficult to maintain the desired shape. Dressing oil stones and grey wheels keeps the abrasive fresh and careful dressing maintains proper flatness or shape.
If you keep the tool's face flat and your stones flat, you'll instantly be working the whole face of the tool when you work on the flat face. The same goes for when you switch to a finer grit stone. There's no wasted time and effort getting the steel to conform to an out of flat stone.
Here's a photo of the wear bevel that forms on the face of a middle pitch single iron. This particular iron is 1 5/8" wide and has been used on beech:
It's easy to see the bright line at the cutting edge. This wear bevel is very shallow in its penetration into the face of the iron but is considerably longer in its length streaming back from the cutting edge.
Yesterday Don and I had the chance to see what it would take to remove the wear bevel. I've always said three or four passes on a freshly dressed medium India stone. Don has been teaching a young guy to prepare stock by hand and our middle pitch trying plane had two days of pretty heavy use in poplar. This is the 2 1/4" wide iron as it came out of the plane:
The discoloration in both these photos, I believe, is caused by wood particles adhering to the steel through adhesive wear. The bright wear bevel is where the heat generated by viscoelastic compression of the wood acts as a catalyst to adhesive wear to the metal and metal particles actually adhere to the wood causing the dulling wear. The color of the wood particles is due to being scorched by the heat. Beech, being more dense, generates more heat so the iron that planed the beech has a darker discoloration.
Don honed the iron while I watched. He prefers to use a fine India as his coarse stone when honing but asked if I wanted him to use a medium India because it would remove the wear faster. I told him I wanted him to hone just like he usually does. It took two passes on a 2" X 8" fine India stone to remove the wear. Not forward and back but just single forward passes. At least he thought he had all the wear gone. I asked him to take a third pass just to make sure because three passes are no big deal and I wanted to be able to post a larger photo if anyone asked.
Here's the iron after those three passes:
The wear bevel is removed all the way to the cutting edge. A fine India is about the same as a 400 grit water stone and the abrasive signatures from the stone run across the iron. What looks like it might be abrasive signatures running the length of the iron is residual oil because that's the direction he wiped the blade. It only takes another three or four passes to remove the abrasive signatures of even a medium India stone when using a freshly dressed translucent hard Arkansas. The translucent stone is about the same as a 6000 grit water stone.
I have no idea how many passes it would take to remove about 1/32" of steel if just working on the bevel but it would be a lot if you hone the whole bevel.
I don't hone the whole bevel. I grind at 25º and hone at about 30º. I grind to keep the honed bevel small, never grinding all the way to the edge unless I have major damage to repair. Those times I do grind at the edge, I do it at 90º to the face of the iron and then restore the bevel but always leaving a small 90º flat to be honed away. I only use coarse (36 grit) grey grinding wheel I keep well dressed.
Here's the honed bevel after grinding to manage its size:
As you can see it's about 1/32". I regrind to shrink the honed bevel when it gets to much more than 1/16". I raise a wire edge when honing the bevel in a pass or two. You don't need to waste time tinkering with a honing guide for a pass or two, it's easy to maintain an accurate enough honing angle for just a pass or two. I only use two stones, and India and a translucent. I to strop but only a pass or two to remove any remnants of a wire edge.
Honing doesn't have to be tedious or slow. It's only a few seconds from dull to sharp using this traditional method. Two stones fit in an area less than a square foot and the stones are boxed so it's just a matter of lifting off the lids and dressing the two stones to set up. Clean-up is just a matter of wiping the stones and putting the lids back on the stones. You are never dealing with more liquid than you can quickly wipe up with a single wipe.
Paul Chapman":30m777hw said:
David C":30m777hw said:
It doesn't take any more effort. In fact, it takes less effort. If one takes care of their sharpening stones and tools, things get pretty easy. If you keep the stones flat and the faces of the tools flat, each sharpening is actually doing the prep work for subsequent sharpening. Abrasives are actually a collection of tiny cutting edges and, like all cutting edges, they get dull. Water stones and white or pink grinding wheels are more friable than oil stones or normal grinding stones so the expose fresh abrasive on their own. The problem with this is that the friable abrasives lose their shape quickly and it's very difficult to maintain the desired shape. Dressing oil stones and grey wheels keeps the abrasive fresh and careful dressing maintains proper flatness or shape.
If you keep the tool's face flat and your stones flat, you'll instantly be working the whole face of the tool when you work on the flat face. The same goes for when you switch to a finer grit stone. There's no wasted time and effort getting the steel to conform to an out of flat stone.
Here's a photo of the wear bevel that forms on the face of a middle pitch single iron. This particular iron is 1 5/8" wide and has been used on beech:
It's easy to see the bright line at the cutting edge. This wear bevel is very shallow in its penetration into the face of the iron but is considerably longer in its length streaming back from the cutting edge.
Yesterday Don and I had the chance to see what it would take to remove the wear bevel. I've always said three or four passes on a freshly dressed medium India stone. Don has been teaching a young guy to prepare stock by hand and our middle pitch trying plane had two days of pretty heavy use in poplar. This is the 2 1/4" wide iron as it came out of the plane:
The discoloration in both these photos, I believe, is caused by wood particles adhering to the steel through adhesive wear. The bright wear bevel is where the heat generated by viscoelastic compression of the wood acts as a catalyst to adhesive wear to the metal and metal particles actually adhere to the wood causing the dulling wear. The color of the wood particles is due to being scorched by the heat. Beech, being more dense, generates more heat so the iron that planed the beech has a darker discoloration.
Don honed the iron while I watched. He prefers to use a fine India as his coarse stone when honing but asked if I wanted him to use a medium India because it would remove the wear faster. I told him I wanted him to hone just like he usually does. It took two passes on a 2" X 8" fine India stone to remove the wear. Not forward and back but just single forward passes. At least he thought he had all the wear gone. I asked him to take a third pass just to make sure because three passes are no big deal and I wanted to be able to post a larger photo if anyone asked.
Here's the iron after those three passes:
The wear bevel is removed all the way to the cutting edge. A fine India is about the same as a 400 grit water stone and the abrasive signatures from the stone run across the iron. What looks like it might be abrasive signatures running the length of the iron is residual oil because that's the direction he wiped the blade. It only takes another three or four passes to remove the abrasive signatures of even a medium India stone when using a freshly dressed translucent hard Arkansas. The translucent stone is about the same as a 6000 grit water stone.
I have no idea how many passes it would take to remove about 1/32" of steel if just working on the bevel but it would be a lot if you hone the whole bevel.
I don't hone the whole bevel. I grind at 25º and hone at about 30º. I grind to keep the honed bevel small, never grinding all the way to the edge unless I have major damage to repair. Those times I do grind at the edge, I do it at 90º to the face of the iron and then restore the bevel but always leaving a small 90º flat to be honed away. I only use coarse (36 grit) grey grinding wheel I keep well dressed.
Here's the honed bevel after grinding to manage its size:
As you can see it's about 1/32". I regrind to shrink the honed bevel when it gets to much more than 1/16". I raise a wire edge when honing the bevel in a pass or two. You don't need to waste time tinkering with a honing guide for a pass or two, it's easy to maintain an accurate enough honing angle for just a pass or two. I only use two stones, and India and a translucent. I to strop but only a pass or two to remove any remnants of a wire edge.
Honing doesn't have to be tedious or slow. It's only a few seconds from dull to sharp using this traditional method. Two stones fit in an area less than a square foot and the stones are boxed so it's just a matter of lifting off the lids and dressing the two stones to set up. Clean-up is just a matter of wiping the stones and putting the lids back on the stones. You are never dealing with more liquid than you can quickly wipe up with a single wipe.
