On 2020-07-03 10:24 p.m., Adam R. Maxwell wrote:
> Catching up on email, I noticed that no one had responded to this, so I'll
offload some of my ignorance here. I grind mine somewhere between 25-30˚, but
can't say if that's historically favored; it's typical on the secondhand planes
I've bought. For a common pitch plane with 45˚ bed angle, that should give you
plenty of clearance, and generally the older steels like O1 or W1 take a fine
edge down to 25˚ (unlike modern A2). For York pitch, you can use a more obtuse
bevel, which I suspect would give you a longer-lasting edge.

Thanks to Adam & the Yorkshireman for their thoughtful replies.  I 
suspected that nobody really knows the bevel & honing angles favoured 
historically for the tapered irons used in infill planes like my Spiers 
panel plane. I am inclined to think they would most often have been used 
on hardwoods, particularly brown oak and mahogany and also exotics - 
rosewood and such. So higher pitched irons might have been favoured, 
except that most if not all of the infills I've seen  were bedded at 45 
deg. or thereabouts. I had been hoping someone more observant than I 
might have noticed certain bevel angles were most common on these 
planes, but it seems maybe not. The few infills with which I have 
experience had bevel angles of about 30 deg when found - higher than I 
would normally use.

In any case, I ground the iron I mentioned previously at 25deg, and 
honed it with microbevels according to the method espoused by our 
recently-departed Brent Beach, and found the plane performed 
wonderfully, easily achieving glassy smoothness on poplar and white oak, 
as well as on tiger/fiddleback maple, a piece with tortuously undulating 
grain. It produced the finest wispiest shavings I've ever cut - 0.0005in 
in each of those 3 species. It remains to be seen how long the edge 
holds up.

FWIW

Don

-- 
“Common sense is the collection of prejudices acquired by age eighteen.” —
Albert Einstein

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thunder. We need the storm, the whirlwind, and the earthquake.”
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