Broaching

[P.J.]

I am not an expert on locks by any strech of the imagination, however I have spent 30 years or more
Machining all kinds of materials with Planers and milling machine, shapers and surface grinders ect. Bobs explantion in his previous post is right about the Planer. However
this bock has been machined with a carbide fly cutter either by the factory or by someone else.A fly cutter is a
round tool with one or more carbide inserts and can range form 2 inch diameter to 12 inch diameter depending on the area to cut with multiple carbide cutters .There is no doubt about it. It cant be a blanchard grinder because thats what is used to grind your flywheel.If the bock had a blemish after it was planed and before it was stamped then
the factory would put it aside and machine them with a fly cutter later on together with other blemished bocks.
If the block then cleaned up and was within the tolerance
then it would then continued to be assembled and then stamped
hope that helps
suprss70