Hop-Hornbeam Ironwood Log: A Notched Log Cradle
#3
I started working the hop-hornbeam log I wrote about last week and discovered things I’d like to share.  I split a lot of firewood by hand 50-60 years ago - I came to love oak and loathe elm - but never tried to process logs for anything other than the fire.  I’m improvising what I’m doing now, and if it seems naive, that’s because it is.  I confess that right up front.   But I am having fun.

One end of my log was badly checked and rotting.  You can see the split between the wheels in this photo.  I decided to make it into a notched cradle for working the rest of the log.
[Image: IMG_2710%201_zps8rfphn07.jpg]
Splitting Off the Rot
I split the piece at the check. Then, to get beyond some rot on the keeper piece, I split another inch off.
Trouble is, a small log gets pretty unstable with a couple steel wedges sticking out the top.  It needed a handle.  I remembered from my youth using a 2’ gooseneck wrecking bar jammed down in the split to control the piece while I pounded wedges with the other hand. I still have the bar.
[Image: IMG_2777_zpspoyr2zr4.jpg]
It worked and made it easy to resist the temptation to put my fingers near the split. (Don’t do that!  There’s a famous sculpture in the Louvre of some ancient hero with his hand trapped in a cleft in a stump.  Unable to escape, he is being devoured by a lion!  I think the pinch alone would be enough punishment.)  
http://www.louvre.fr/en/oeuvre-notices/milo-croton-0

Flattening the Split
The split surface was irregular.  I tried flattening with the big chisel.  No go -  too straight and precise for this tough ironwood surface.  Before getting the scrub plane, I tried an axe, not to chop, but to shear back-and-forth with the curved bit as I slid the axe down the piece.  
[Image: IMG_2798_zpst8yb1l9t.jpg]
It was soon flat and stable.  Advisable to wear gloves for this so as not to ram slivers up under the fingernails.
Big Grin   The scrub plane or drawknife might be easier, but the axe was pretty effective.

A Surprising Thing Happened
Then I cut the notch on the other side.  Sawed some kerfs to define the notch and removed bulk waste with a big chisel.  As I refined the bottom with the scrub plane, a surprising thing happened.  Instead of becoming scalloped, the bottom of the notch became smooth and followed a nice arc.  Then the cutting stopped.  It seemed to reach a limit where the width of the sole bridged the arc high enough that the blade no longer reached the wood.  To cut more, I extended the blade.  When the cutting stopped again, I had scrubbed a deeper curve.  
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I think the curve gets started because the scrub plane lacks a rabbet mouth, so it can’t cut into the corners at the ends of the notch.  The plane droops away from the ends of the notch, and the arc results.  It's like trying to cut rabbets with an ordinary plane.  The width of the sole and the vertical blade projection determine the limiting radius at which cutting stops.  The curvature of the blade itself may also come into play in a complicated way.  Here I reproduced the arc in KD lumber.
[Image: IMG_2805_zpsitpbn8ru.jpg]
I don’t know if this will be useful for anything, but I found it really interesting to observe and fun to play with.  Next come some ironwood wedges.
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#4
Very interesting!

Similarly, one time I had a plane with a slightly bowed bottom (long story, a wooden plane).  I couldn't believe how subtly but repeatedly it could "dish" a long piece of wood, after a few strokes.

Chris
Chris
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