I have a very early #40. The grind on it is similar to Ed's. 

I haven't run into a lot of rough sawn lumber than required substantial
scrubbing but it works a charm when needed. I also find it useful for taking
down the edge of a board when the amount to remove is < 1" as opposed to
ripping.

Dennis

-----Original Message-----
From: oldtools@g...  On Behalf Of Ed Minch
Sent: Friday, May 7, 2021 9:54 AM
To: Chris Wolf 
Cc: porch 
Subject: Re: [oldtools] Scrub planes

And just for a data point, here is the Stanley idea of the proper grind on a
later NIB #40.  The blade is just shy of 1/8” thick.  I find these tools easy to
use and quite effective.  I could never imaging doing so much removal with a
bench plane with a convex grind.