Ken Shepard wrote:
>> From the 1939 Stanley catalog:
>
> "Some workmen are of the opinion that corrugated bottom planes slide easier
> on resinous woods."
>
> Stanley got a small premium for the corrugations.  A No. 6 sold for $7.75
> in 1939 vs. $8.15 for the 6C.
>
> I have found them easier to flatten - less metal to remove - but can tell
> no difference in use.

I think workshop flattening of plane soles vastly(*) post-dates
the creation of corrugations and is (hence) most
unlikely to be the reason for them.

  BugBear

(*) and then some
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