KELIBRON Course · 6 lessons · Coming soon
Tolerances, limit gauges and pass or fail
Six lessons on deciding whether a part is good: limits and fits, IT grades and fundamental deviations, general tolerances, acceptance limits, go and no-go limit gauges, and choosing an instrument for the tolerance. Lessons go live one by one as their articles and practice are ready.
Who it is for
For students and inspectors who can read a caliper. Take the caliper course first.
Lessons
- Limits and fits Coming soon
- IT grades and fundamental deviations Coming soon
- General tolerances Coming soon
- Acceptance limits and safety margins Coming soon
- Go and no-go limit gauges Coming soon
- Choosing an instrument for the tolerance Coming soon
Lesson 1 · Coming soon
Limits and fits
Work out the limits of a toleranced size and name the type of fit.
You will be able to
- Calculate upper limit, lower limit and tolerance from the deviations.
- Read a hole or shaft tolerance such as H7 or g6.
- Tell clearance, transition and interference fits apart.
Lesson 2 · Coming soon
IT grades and fundamental deviations
Look up the limits of a size given with a tolerance code such as H7.
You will be able to
- Explain what the IT grade and the fundamental deviation each set.
- Find the limits of a hole and a shaft from the tables.
- Check a measured size against limits taken from the tables.
Lesson 3 · Coming soon
General tolerances
Find the tolerance of a dimension that has none written next to it.
You will be able to
- Find the tolerance class named on the drawing.
- Look up the permitted deviation for a size in that class.
- Judge a measured size against a general tolerance.
Lesson 4 · Coming soon
Acceptance limits and safety margins
Decide pass or fail when a reading is close to a limit.
You will be able to
- Explain why measurement uncertainty matters near a limit.
- Work out acceptance limits from the specified limits and a safety margin.
- Compare the reading with the acceptance limits to decide pass or fail.
Lesson 5 · Coming soon
Go and no-go limit gauges
Check a hole or a shaft with a limit gauge.
You will be able to
- Tell what the go end and the no-go end each check.
- Use a gauge without forcing it.
- Know why a passing no-go end always rejects the part.
Lesson 6 · Coming soon
Choosing an instrument for the tolerance
Pick the instrument that can decide a given tolerance.
You will be able to
- Apply the 10:1 rule between the tolerance and the instrument’s accuracy.
- Choose between a caliper and a micrometer for a tolerance.
- Tell resolution from accuracy when choosing an instrument.
More courses
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