ANGLE GAGE BLOCK HEADER PAGE
PREVIOUS
NEXT
Angle Gage Block & True Square Tolerances:

							
Reference
Grade
Calibration
Grade
Working
Grade
  Max. Deviation from Nominal Angle

  Material

  Flatness of Gaging Surface

  Flatness & Parallelism of Sides

  Surface Finish (Gaging Surfaces Only)


  Squareness of Sides to Gaging Surfaces

  Estimated Uncertainty of Measurement (k=2)
±1.0 seconds

croblox®

6 µin. (0.15 µm)

8 µin. (0.20 µm)

0.4 µin.AA
(0.01 µm AA)

6 seconds

0.6 Seconds
±2.0 seconds

Steel

8 µin. (0.15 µm)

8 µin. (0.20 µm)

0.6 µin.AA
(0.015 µm AA)

8 seconds

1.0 Seconds
±5.0 seconds

Steel

14 µin. (0.15 µm)

16 µin. (0.20 µm)

1.0 µin.AA
(0.025 µm AA)

12 seconds

3.5 Seconds
Note:  Angle gage blocks are made to Webber Gage specifications.  There is not currently a U.S. or international standard
for Angle Gage Blocks and True Squares.
 
NOTE:  THE ALTITUDES OF ANGLE GAGE BLOCKS ARE NOT FINISHED.  (See Below.)  For 15°, 30°, and 45° angle
blocks, the altitude may be finished as a special order at additional cost.   

				
Why are tolerances LM, SI, and TR no longer available?
Notice of recent changes in angle block calibration (pdf document)

				
Physical Dimensions:  
Angle Blocks
NOTE:  THE ALTITUDES OF ANGLE GAGE BLOCKS ARE NOT FINISHED.  For 15°, 30°, and 45° angle blocks,
the altitude may be finished as a special order at additional cost.   
Reference Grade Calibration Grade Working Grade
Length of Base 2 inches 2 inches 4 inches
Width of Base 1 inch 1 inch 5/8 inch
Thickness, 15°, 30°, 45° 1/4 inch 1/4 inch 1/4 inch
Thickness, All others 3/8 inch 3/8 inch 1/4 inch
Knife Edges and Parallels
Working Grade Only Knife Edge Parallel
Length 6 inches 6 inches
Width of Base 5/8 inch 5/8 inch
Thickness 3/4 inch 1/2 inch
True Squares
Reference Grade
TS 21.R
Calibration Grade
TS 21.C
Working Grade
TS 44.W
Working Grade
TS 66.W
Length of Base 2 inches 2 inches 4 inches 6 inches
Width of Base 1 inch 1 inch 5/8 inch 5/8 inch
Center Holes 1/2 inch 1/2 inch 2 inch 2 inch
Auxiliary Holes --- ---
8 Holes 21/64" Dia.
on 3" BCD
8 Holes 21/64" Dia. on 3" BCD
NEXT
PREVIOUS
ANGLE GAGE BLOCK HEADER PAGE
AG2
©2011, Webber Gage Division, The L. S. Starrett Co, Cleveland, Ohio , 44145
INDEX