David Weaver
03-03-2014, 10:02 AM
Well, I posted the topic with a question mark, but I really don't need to use one.
http://planetuning.infillplane.com/html/cap_iron_study_by_kees_van_der.html
I tracked down this article that's posted on Steve Elliot's site. Who is steve elliot? One of the two (the other being Bill Tindall) who went to the trouble to dig up the kato and kawai stuff, as bill has clarified - for the purpose of studying wear, but with the lovely side benefit of providing a close up visual of a double iron in use.
All of the numbers in the article make my head spin, but there are a lot of folks who need to see numbers and comparisons before they'll believe much. It does quantify some of the things we've talked about (how does common pitch with a cap iron compare to steep pitch). And a separate conclusion that I've been beating the drum about for a while, that the cap iron is extremely useful in a heavy cut to limit tearout to something that can easily be removed by a smoother - something that is not managed well with a single iron in a heavy cut in something like quartered wood.
Yesterday, I was flattening door panels, and I had one that I had to thickness (the lumber I have to work with is various thicknesses), which is a painful job when the lumber is overthick to start with. It's 6/4 quartered cherry, which tears out. I jacked the thickness off of the board and then used a try plane to level it and measured the shavings (somethign I almost never do) in a very heavy cut - .011 once all of the humps were out, with minimal tearout - some very light depth tearing but nothing that I couldn't remove with a quick follow up by a metal jointer set cutting .005".
I would never have thought of making cuts like those pre-double iron, and if I had tried, I would've gone past my depth mark or spent 20 minutes taking off the last 16th with some steep angle plane with a heavy smoother set.
Thanks for taking the considerable time, Kees, that it does to catalog and organize your thoughts with this stuff.
http://planetuning.infillplane.com/html/cap_iron_study_by_kees_van_der.html
I tracked down this article that's posted on Steve Elliot's site. Who is steve elliot? One of the two (the other being Bill Tindall) who went to the trouble to dig up the kato and kawai stuff, as bill has clarified - for the purpose of studying wear, but with the lovely side benefit of providing a close up visual of a double iron in use.
All of the numbers in the article make my head spin, but there are a lot of folks who need to see numbers and comparisons before they'll believe much. It does quantify some of the things we've talked about (how does common pitch with a cap iron compare to steep pitch). And a separate conclusion that I've been beating the drum about for a while, that the cap iron is extremely useful in a heavy cut to limit tearout to something that can easily be removed by a smoother - something that is not managed well with a single iron in a heavy cut in something like quartered wood.
Yesterday, I was flattening door panels, and I had one that I had to thickness (the lumber I have to work with is various thicknesses), which is a painful job when the lumber is overthick to start with. It's 6/4 quartered cherry, which tears out. I jacked the thickness off of the board and then used a try plane to level it and measured the shavings (somethign I almost never do) in a very heavy cut - .011 once all of the humps were out, with minimal tearout - some very light depth tearing but nothing that I couldn't remove with a quick follow up by a metal jointer set cutting .005".
I would never have thought of making cuts like those pre-double iron, and if I had tried, I would've gone past my depth mark or spent 20 minutes taking off the last 16th with some steep angle plane with a heavy smoother set.
Thanks for taking the considerable time, Kees, that it does to catalog and organize your thoughts with this stuff.