James Waldron
04-09-2016, 6:46 PM
A number of pretty good concepts were recently presented in "The Donkey Ear Experiment" http://www.sawmillcreek.org/showthread.php?242236-The-Donkey-Ear-Experiment and that got my brain spinning (not an unusual condition) and led me to a brilliant new concept that will amaze and impress you all (blush). I have now built a proof of concept structure with four goals in mind:
The work-piece needs to lie flat on a horizontal surface, not sticking up in the air on a ramp where it may not be entirely stable;
The cheek of the shooting plane must be supported so the user is not fighting gravity to hold the proper engagement with the work-piece;
The support of the sole of the plane must be kept in the proper angle to assure an accurate result; and
The planed face of the work-piece must attain a reproducible and consistent angle.
All my bench planes are light weight shop-built woodies. I wanted to eliminate that as a potential question mark, so I picked up an old, inexpensive Stanley Bailey 5 1/2. That has enough mass to power through pretty tough stuff. (I'll try the thing with one of my woodies, too, but first things first.) The 5 1/2 has a lot more clean-up to go, but I got the sole flat and polished, the blade sharp, square and straight (don't want camber on a shooting board), and did a bit of tuning on the chip breaker. At that point, the plane made very satisfactory lace shavings (1 mil or so). And it did thicker shavings just as well.
Now for the shooting board itself:
A substantial piece of left-over 3/4 inch plywood was available, so it's what I used. Pretty tatty stuff, but it's not going to be a tool, just a proof of concept, so no problem. It was a bit fiddley to work out the dimensions (and after my test drive, I have a bit more fiddling to do). And I learned that when I get more serious about a working tool, the order of steps may be important to attain the required precision and accuracy.
Maybe I should have been more concerned with precision and accuracy this time around. I ended up with a bit of twist in the shot face, maybe 1 to 1.5 degrees. At least I know where it came from (and why that order of steps may be important). And I had to make a small adjustment to one part that threw off the primary ramp height just enough to leave a tiny gap where the sole of the plane is not supported for it's full length. Works okay, but it's irritating.
The fence for the work-piece didn't hit dead square, so the work-piece sits just a touch, about 1 degree or so, out of square, and the resulting planed surface comes out tapered just a tiny amount. Adjusting the fence to square is well-known, so I skipped it on this build; I'll certainly take care of that the next time around.
Construction is pretty simple and easy to understand by inspection:
335465
And how the plane is supported is also pretty apparent:
335466
As you can see, the 5 1/2 is taking very nice, curly shavings, even on end grain. Those shavings were the result of my first test drive with a piece of BORG red oak. I started from the square edges and chamfered the piece on four edges:
335467
I feel I have attained all four of my specific goals. With this first "quick and dirty" assembly, I've learned enough to build another with accuracy and precision and be very satisfied with the effort.
For many, this structure will not be worth the bother. It's a lot more effort and a lot more detail than the simple ramp approach others have relied on for some time. On the other hand, for anyone who builds a lot of boxes or other work with miter joints .... I'm planning to make two, one at 45 degrees and another at 22.5 degrees for octagonal shapes.
The work-piece needs to lie flat on a horizontal surface, not sticking up in the air on a ramp where it may not be entirely stable;
The cheek of the shooting plane must be supported so the user is not fighting gravity to hold the proper engagement with the work-piece;
The support of the sole of the plane must be kept in the proper angle to assure an accurate result; and
The planed face of the work-piece must attain a reproducible and consistent angle.
All my bench planes are light weight shop-built woodies. I wanted to eliminate that as a potential question mark, so I picked up an old, inexpensive Stanley Bailey 5 1/2. That has enough mass to power through pretty tough stuff. (I'll try the thing with one of my woodies, too, but first things first.) The 5 1/2 has a lot more clean-up to go, but I got the sole flat and polished, the blade sharp, square and straight (don't want camber on a shooting board), and did a bit of tuning on the chip breaker. At that point, the plane made very satisfactory lace shavings (1 mil or so). And it did thicker shavings just as well.
Now for the shooting board itself:
A substantial piece of left-over 3/4 inch plywood was available, so it's what I used. Pretty tatty stuff, but it's not going to be a tool, just a proof of concept, so no problem. It was a bit fiddley to work out the dimensions (and after my test drive, I have a bit more fiddling to do). And I learned that when I get more serious about a working tool, the order of steps may be important to attain the required precision and accuracy.
Maybe I should have been more concerned with precision and accuracy this time around. I ended up with a bit of twist in the shot face, maybe 1 to 1.5 degrees. At least I know where it came from (and why that order of steps may be important). And I had to make a small adjustment to one part that threw off the primary ramp height just enough to leave a tiny gap where the sole of the plane is not supported for it's full length. Works okay, but it's irritating.
The fence for the work-piece didn't hit dead square, so the work-piece sits just a touch, about 1 degree or so, out of square, and the resulting planed surface comes out tapered just a tiny amount. Adjusting the fence to square is well-known, so I skipped it on this build; I'll certainly take care of that the next time around.
Construction is pretty simple and easy to understand by inspection:
335465
And how the plane is supported is also pretty apparent:
335466
As you can see, the 5 1/2 is taking very nice, curly shavings, even on end grain. Those shavings were the result of my first test drive with a piece of BORG red oak. I started from the square edges and chamfered the piece on four edges:
335467
I feel I have attained all four of my specific goals. With this first "quick and dirty" assembly, I've learned enough to build another with accuracy and precision and be very satisfied with the effort.
For many, this structure will not be worth the bother. It's a lot more effort and a lot more detail than the simple ramp approach others have relied on for some time. On the other hand, for anyone who builds a lot of boxes or other work with miter joints .... I'm planning to make two, one at 45 degrees and another at 22.5 degrees for octagonal shapes.