Tolerance on centre distance between two dowels
Tolerance on centre distance between two dowels
(OP)
Hi
I am looking a two dowels separated by a distance D which must match up with two holes on a corresponding part.
The fit between the dowel/hole is to be a H7/g6 close sliding fit.
The max shaft diameter under this spec is 9.995, the min hole diameter is 10.000 under this spec.
Surely in order for these two parts to go together under all circumstances then the tolerance on the centre distance must be +/-0.005, please see attached pic. Or perhaps even less than this as if the distance between the dowels was D+0.005 and the distance between the holes was D-0.005 then the overall difference would be 0.01.
How easy are the tolerances to achieve they seem crazy!?
I am looking a two dowels separated by a distance D which must match up with two holes on a corresponding part.
The fit between the dowel/hole is to be a H7/g6 close sliding fit.
The max shaft diameter under this spec is 9.995, the min hole diameter is 10.000 under this spec.
Surely in order for these two parts to go together under all circumstances then the tolerance on the centre distance must be +/-0.005, please see attached pic. Or perhaps even less than this as if the distance between the dowels was D+0.005 and the distance between the holes was D-0.005 then the overall difference would be 0.01.
How easy are the tolerances to achieve they seem crazy!?





RE: Tolerance on centre distance between two dowels
RE: Tolerance on centre distance between two dowels
Your tolerance is way too accurate. One of your clearance holes should be a slot. Problem solved.
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JHG
RE: Tolerance on centre distance between two dowels
Greg
RE: Tolerance on centre distance between two dowels
RE: Tolerance on centre distance between two dowels
John Acosta, GDTP Senior Level
Manufacturing Engineering Tech
RE: Tolerance on centre distance between two dowels
The other option is to drill the dowel holes after assembly, making your assembly repeatable, rather than accurate. Any time I have seen two dowels in accurate clearance holes, this is how it has been done.
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JHG