Service Bulletin: SB 028.1
Subject: Sidewall Blanking Dies — Tooling
Since 1973 PMC has supplied sidewall blanking dies with thermally heat treated punch and die sections tempered to tool steel full recommended hardness. This was a change from our previous standard of a semi-hard die section, which allowed a shear-in procedure when resharpening the punch and die per PMC Service Manual, page 27.
With the introduction of fully hardened punch and die sections the practice of peening and shearing the lower die was no longer applicable. While this tool practice had its advantages we have found that the exceptional die wear gained with both sections fully hardened more than offset the more critical need to grind and fit upper and lower sections if required.
To assist all customers in either internally or contractually having dies sharpened we have prepared a more detailed procedure outline for local tool maker’s use. The attached procedure we expect will be of assistance to all customers.
If for any reason a sidewall die is not known as to whether it is of the new hardness the procedure attached can be safely applied in either case. The only precaution is that a known harden die can not be peened and sheared as with earlier tooling.
As an added note of information to all customers, PMC now provides as standard, fully hardened sidewall dies, as-described, which have also been cryogenically treated for the maximum abrasion resistance obtainable.