Craftsman's Cribsheet No. 78: Straightness of Cold Finished Steel Bars
The straightness of cold finished steel bars, and all other barstock for our machines, is of critical importance.
The straightness of cold finished steel bars, and all other barstock for our machines, is of critical importance. The controlling standard is ASTM A 108, Table A1.4. However, the standard errs in claiming the tolerances are measured by placing the bars on a level table and the depth of the arc then measured with a feeler gage and straight edge. While that will give a value for the maximum departure from straightness, it does not actually describe the true geometric relationship.
All Craftsman’s Cribsheets are available for viewing and download at short.productionmachining.com/cribsheets.
Related Content
-
Craftsman Cribsheet No. 126: AISI System of Identification
Source: PMPA Prior to the Society of Automotive Engineers taking responsibility for Steel Grade nomenclature in the United States (1995), the American Iron and Steel Institute determined U.S. standard steel grades in collaboration with SAE.
-
Craftsman Cribsheet No. 128: Why Do Machinists Say Tenths Instead of Ten Thousandths?
In machinist parlance, a tenth is a tenth of a thousandth, not a tenth of an inch.
-
Keeping It In The Family — Succession Tips From Those Who Lived It | Part 1
PMPA members share some tips to avoid getting burned when passing the business torch from one family member to another.
