A composite inspection in which the work gear is spring-loaded into zero-backlash mesh with a master gear, so both flanks touch at once, and the change in center distance is recorded through a full turn. Total radial composite deviation captures runout and size variation, and tooth-to-tooth composite deviation captures local errors such as nicks. It is quick and widely used on production floors, though it mixes left and right flank errors together.
Double-flank test shows a big spike once per rev, there's a nick on a tooth, deburr and roll it again.
Also heard as
- double-flank composite test
- radial composite test
- roll test
Do not mix it up with
- Single-flank test: The single-flank test runs at working center distance with backlash and measures motion error on one flank, much closer to real operation.
Related terms
Roll check
Shop name for rolling a production gear against a master gear to catch size errors, runout and nicks.
Single-flank test
Running a gear against a master at fixed center distance and measuring rotational error on one flank only.
Runout
How much the teeth wobble radially relative to the gear's axis, measured with a probe in each tooth space.
Center distance
The distance between the axes of two meshing gear shafts, set by the housing bores.