Gagemakers Tolerances
| Nominal Size | Tolerances | ||||
|---|---|---|---|---|---|
| Above | To and Including | XX | X | Y | Z |
| .029— .740 mm |
.825 20.96 mm |
.00002 .00051 mm |
.00004 .00102 mm |
.00007 .00178 mm |
.00010 .00254 mm |
| .825— 20.96 mm |
1.510 38.35 mm |
.00003 .00076 mm |
.00006 .00152 mm |
.00009 .00229 mm |
.00012 .00305 mm |
| 1.150— 38.35 mm |
2.510 63.75 mm |
.00004 .00102 mm |
.00008 .00203 mm |
.00012 .00305 mm |
.00016 .00406 mm |
| 2.510— 63.75 mm |
4.510 114.55 mm |
.00005 .00127 mm |
.00010 .00254 mm |
.00015 .00381 mm |
.00020 .00508 mm |
| 4.510— 114.55 mm |
6.510 165.35 mm |
.000065 .00165 mm |
.00013 .00330 mm |
.00019 .00483 mm |
.00025 .00635 mm |
| 6.510— 165.35 mm |
9.010 228.85 mm |
.00008 .00203 mm |
.00016 .00406 mm |
.00024 .00610 mm |
.00032 .00813 mm |
| 9.010— 228.85 mm |
12.010 305.05 mm |
.00010 .00254 mm |
.00020 .00508 mm |
.00030 .00762 mm |
.00040 .01016 mm |
How to Order Cylindrical Plug and Ring Gages
- Quantity and whether Go or No Go Member
- Exact Diameter of Member
- Z, Y, X, XX Tolerance
- Type of Material Required — Steel — Hard Chrome — Carbide
- Type of Gage: Reversible — Taperlock — Trilock — Progressive Plug — Ring — Master Setting Disc
- Whether Handles are Required if Plug
- Marking Instructions
Direction of Tolerance
The following will apply to all gages unless otherwise specified:
- GO Cylindrical Plug gages — Plus tolerance (+)
- NO GO Cylindrical Plug gages — Minus tolerance (−)
- Master Cylindrical Plug gages — Bilateral tolerance (±)
- GO Cylindrical Ring gages — Minus tolerance (−)
- NO GO Cylindrical Ring gages — Plus tolerance (+)
- Master Cylindrical Ring gages — Bilateral tolerance (±)
A rule of thumb regarding tolerances on gages is to use 10% of the total manufacturing tolerance of piece part for gages, with 1/2 of the 10% to be applied against the GO and 1/2 of the 10% to be applied on the NO GO.
Example #1
Part Size = .250 + .002/−.000
GO = .250 NO GO = .252
Total Manufacturing Tolerance = .002
10% of .002 = .0002
1/2 of .0002 = .0001
Class Z Recommended
Example #2
Part Size = .250 + .0005/−.0000
GO = .250 NO GO = .2505
Total Manufacturing Tolerance = .0005
10% of .0005 = .00005
1/2 of .00005 = .000025
Class XX Recommended