Reply by mvflaim

All Bedrock planes are designated with the 600 series numbers on the bed. The very early Bedrocks that have round sides are very similar to later versions of Bailey planes with both having frog adjustment screws behind the frog.

Later versions of Bedrock planes have square sides and new frog adjustment screws making it possible to move the frog forward and back without removing the blade.

If you see a so-called Bedrock plane that does not have a 600 series number on the bed, it’s not a Bedrock plane.

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