Expressing dimensions, tolerance, clearance... ??
Expressing dimensions, tolerance, clearance... ??
(OP)
Hi
Imagine I have designed a part that fits inside another one.
For example a block with a 1cm diameter hole, and a 1cm diam cylinder piece that fits in that hole.
How do I express their dimensions/tolerance/gap/clearance in such a way that this cylinder can be introduced in the hole? As tight as possible but being able to move.
I guess that just writing that both have 1cm diameter would be wrong because their surfaces would overlap.
and saying 1.00+-0.01cm for both pieces could imply that the inner piece could be bigger than the outer one.
Do I need to say 1.00cm, 1.00-gap cm for the other one? being gap >=2*tolerance
I mean what's the proper way that could be understood by a manufacturer.
Imagine I have designed a part that fits inside another one.
For example a block with a 1cm diameter hole, and a 1cm diam cylinder piece that fits in that hole.
How do I express their dimensions/tolerance/gap/clearance in such a way that this cylinder can be introduced in the hole? As tight as possible but being able to move.
I guess that just writing that both have 1cm diameter would be wrong because their surfaces would overlap.
and saying 1.00+-0.01cm for both pieces could imply that the inner piece could be bigger than the outer one.
Do I need to say 1.00cm, 1.00-gap cm for the other one? being gap >=2*tolerance
I mean what's the proper way that could be understood by a manufacturer.






RE: Expressing dimensions, tolerance, clearance... ??
This really isn't that complicated, if the maximum dimension of the cylinder is less than minimum dimension of the hole, then there will be no interference.
TTFN
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RE: Expressing dimensions, tolerance, clearance... ??
RE: Expressing dimensions, tolerance, clearance... ??
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
RE: Expressing dimensions, tolerance, clearance... ??
TTFN
FAQ731-376: Eng-Tips.com Forum Policies
RE: Expressing dimensions, tolerance, clearance... ??
I mean even an interference fit will still move if you apply enough force.
RE: Expressing dimensions, tolerance, clearance... ??
Imagine I want to say that my pieces measure 10mm and I want a clearence fit RC3 (precision running fit) and a tolerance of 0.1mm.
How and where should I write all this?
RE: Expressing dimensions, tolerance, clearance... ??
RE: Expressing dimensions, tolerance, clearance... ??
Typically these drawings should be created in accordance with an industry drawing standard.
These vary some by location & industry but the primary one in the US is ASME Y14.5.
Most of the rest of the world use ISO, or their local variations.
Are these production parts or some kind of captive tooling/test fixture or similar? In the latter case you can sometimes get away with more 'so long as the parts work'.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Expressing dimensions, tolerance, clearance... ??
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Expressing dimensions, tolerance, clearance... ??
I'm reading the ASME and ISO standards.