In
the previous post, I finished the primary excavation. That left me with a flat bed, though it was narrower than it needed to be. I needed to extend the bed to the full width of the iron, plus 1/16", and this would create the abutments and form the recesses for the iron and wedge. Here's how it was done.
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| Used a flush-cut saw down to the 1/4" line, referencing off the bed ... |
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| ... but used a 0.019" thick cereal box shim to ensure not going below the bed line |
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| For the final plane, I used a 0.010" thick brass shim |
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| Can't see them here, but I also marked 1/4" depth lines on the saw blade so that I wouldn't saw too deep |
For the cut that defines the front aspect of the abutment recess, I made a temporary sawing guide at the combined angle of the iron and wedge and screwed it to the bed. I was able to use the layout lines on the plane body to figure out the angle.
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| The temporary sawing guide screwed to the bed |
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| In this close-up, you can see I positioned the guide so that the thickness of the saw will get me to the cut line |
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| Then I sawed to 1/4" depth ... |
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| ... and I'm left with the abutment recess delineated |
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| Then some careful paring gets the side walls down to the sawn lines |
You can see that my shims left me some material to pare away. But the nice, flat bed gave a good surface to reference a chisel against to pare that down even with the bed. That was the reason, BTW, that I used the thinner shim on the final plane - paring the leftover bit on the prototype from using the 0.019" thick shim was harder than it needed to be.
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Here's the completed abutment recess on the final plane.
The slot for the cap-iron screw has also been drilled and chiseled out. |
The next step in shaping the throat was to widen the front aspect. I showed the following sketch a couple weeks ago when posting about throat geometry. The throat is widened by cutting down from "1" to "3", with the saw angled to cut 1/4" deep at "1" and not at all at "3".
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| Throat widened at front |
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| Cutting at an angle - you can see the teeth down deep are not engaged in wood |
Then it's a matter of paring away the waste to get a smooth side wall, angled at top. Finally, I marked and cut to lines for the "eyes", the softened edges that spare tender fingers when clearing the throat of shavings.
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| "Eyes" laid out |
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On the prototype, I pared about the same amount on top as on sidewall (basically 45° paring).
That was a mistake that I corrected on the final plane, cutting more on the sidewall than on the top. |
I'll continue next time with the wedge, first cuts and final shaping.
