Corneel
Established Member
It's now more then a year since the Kato/Kawai video was republished. I'm sure everyone has a lot of practice now, and might have found some little practical tricks. Let's share some experience.
For me, the single most difficult thing is preparing the capiron so it sits flush with the back of the blade with no light showing through. When you use the capiron very close to the edge, any small gap is an entry point for the shaving to pry it open and shove itself under the caprion. Most every capiron in my shop wasn't flat enough. I could have bought precision machined LN capirons and been done with it, but being a cheapskate I choose to repair the old ones. They usually are convex, so I start with narrow pieces of sandpaper on a glassplate to make it concave first. Using somewhat wider pieces I slowly work the concavity flatter until I am done. Check often, it's easy to go too far and recreate the convexity again.
With some capirons it is very difficult to adjust it very close to the edge. Especially when tightening the screw, the capiron seems to move again. I don't really have an answer for this. Sometimes it is a problem with the screw being off to one side, so putting pressure on one side only. Or the capiron just slips around because everything is too smooth. Roughing up the caprion at the top end might help a little bit. If nothing helps I tend not to use that plane anymore or use it as a jackplane.
With the capiron resting nicely flat on the back of the iron, it's time to think about the angle of the leading edge of the capiron. I know that the Japanese video encourages to use a very steep angle, something like 75 degrees. I've seen older German documents where they even use a 90 degree wall. So first this was were I was heading. Problem with such a steep leading edge is the increased effort of pushing the plane. And I don't know exactly what happens to the wood when you put so much pressure onto it.
So I have been experimenting with much lower angles lately. This on advice from Caspar Labarre, a Dutch cabinetmaker with a deep interest in historic woodworking methds. In my Stanley smoother I now use a 45 degree angle. Of course, you need to set the capiron closer to the edge, compared to the higher angled capiron. But it pays of in much reduced effort to push the plane.
In my wooden smoother I even use a lower angle, about 35 degrees. According to Caspar you have an extra mechanism in a wooden plane. The shaving curls forward and hits the wear of the plane, then curves back and forth between capiron and wear until it exits from the thoat of the plane. These curls have friction between these two walls and thus help to support themselves. So you can get away with less support from the capiron itself, because you have this extra support higher up. I don't know if it really works like this, but I do know now that such a low angle works. You have to set the capiron really close to the edge of course. Pushing the plane now feels as if there is no chipbreaker effect going on at all, but you still have the benefit of no tear out.
I happen to have two 49 degree planes with a double iron. I didn't do any structural analyzing of these, but subjectively I'd say they perform a little better on very curly grain.
In none of my planes I use a very tight mouth. Bailey style planes benefit from the extra support under the blade when you pull the frog back. And a really tight mouth in a wooden plane is a rare occurance, not often found in the wild. Because the chipbreaker effect is so strong, I don't feel faffing around with all kinds of combinations of tear out reduction methods is worthwhile. And when everything gets too tight around the mouth, clogging is just waiting to happen. But I'm sure others will feel different about this.
Hope this encourages some discussion. As usual everyones opinion will be different, which isn't a problem, but do expect a ribbing when you post downright nonsence. :mrgreen:
For me, the single most difficult thing is preparing the capiron so it sits flush with the back of the blade with no light showing through. When you use the capiron very close to the edge, any small gap is an entry point for the shaving to pry it open and shove itself under the caprion. Most every capiron in my shop wasn't flat enough. I could have bought precision machined LN capirons and been done with it, but being a cheapskate I choose to repair the old ones. They usually are convex, so I start with narrow pieces of sandpaper on a glassplate to make it concave first. Using somewhat wider pieces I slowly work the concavity flatter until I am done. Check often, it's easy to go too far and recreate the convexity again.
With some capirons it is very difficult to adjust it very close to the edge. Especially when tightening the screw, the capiron seems to move again. I don't really have an answer for this. Sometimes it is a problem with the screw being off to one side, so putting pressure on one side only. Or the capiron just slips around because everything is too smooth. Roughing up the caprion at the top end might help a little bit. If nothing helps I tend not to use that plane anymore or use it as a jackplane.
With the capiron resting nicely flat on the back of the iron, it's time to think about the angle of the leading edge of the capiron. I know that the Japanese video encourages to use a very steep angle, something like 75 degrees. I've seen older German documents where they even use a 90 degree wall. So first this was were I was heading. Problem with such a steep leading edge is the increased effort of pushing the plane. And I don't know exactly what happens to the wood when you put so much pressure onto it.
So I have been experimenting with much lower angles lately. This on advice from Caspar Labarre, a Dutch cabinetmaker with a deep interest in historic woodworking methds. In my Stanley smoother I now use a 45 degree angle. Of course, you need to set the capiron closer to the edge, compared to the higher angled capiron. But it pays of in much reduced effort to push the plane.
In my wooden smoother I even use a lower angle, about 35 degrees. According to Caspar you have an extra mechanism in a wooden plane. The shaving curls forward and hits the wear of the plane, then curves back and forth between capiron and wear until it exits from the thoat of the plane. These curls have friction between these two walls and thus help to support themselves. So you can get away with less support from the capiron itself, because you have this extra support higher up. I don't know if it really works like this, but I do know now that such a low angle works. You have to set the capiron really close to the edge of course. Pushing the plane now feels as if there is no chipbreaker effect going on at all, but you still have the benefit of no tear out.
I happen to have two 49 degree planes with a double iron. I didn't do any structural analyzing of these, but subjectively I'd say they perform a little better on very curly grain.
In none of my planes I use a very tight mouth. Bailey style planes benefit from the extra support under the blade when you pull the frog back. And a really tight mouth in a wooden plane is a rare occurance, not often found in the wild. Because the chipbreaker effect is so strong, I don't feel faffing around with all kinds of combinations of tear out reduction methods is worthwhile. And when everything gets too tight around the mouth, clogging is just waiting to happen. But I'm sure others will feel different about this.
Hope this encourages some discussion. As usual everyones opinion will be different, which isn't a problem, but do expect a ribbing when you post downright nonsence. :mrgreen:
