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Diametrical limit on the diameter to gain greater runout tolerance.

Diametrical limit on the diameter to gain greater runout tolerance.

Diametrical limit on the diameter to gain greater runout tolerance.

(OP)
The bottom Dia 5.31/5.61 is tied up to the 6.0/6.3 long bore with a concentricity defined the attached picture. The feature is difficulty to measure especially at the machine side. what tolerance to lose some diametrical limit on the Dia 5.31/5.61 & Dia 6.0/6.3 diameters to gain greater runout tolerance. Please find the attached picture.

RE: Diametrical limit on the diameter to gain greater runout tolerance.

Your question brings a lot of confusion.

First, what drawing standards do you follow, ISO, or ASME?
From the appearance of dimensions I assume ASME.

Second, if you are using ASME, most likely you will not benefit from using Concentricity.
Third, you mention Runout, but you didn’t specify Runout anywhere on your drawing.
I assume you mix runout and concentricity, and this is something you have to set straight.

Fourth, Runout will not become “greater” if you change size tolerance. Runout is always specified RFS (and everything on your drawing is specified RFS)
I assume you are thinking about Position and bonus tolerance, which is not the case here.

And finally, you want to “loosen” tolerances because they are difficult to measure? So your tolerances were wrong in the first place?

I think you have some 'splaining to do.


RE: Diametrical limit on the diameter to gain greater runout tolerance.

Since there are commas for decimal dividers, I'm betting its ISO style.

John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems

RE: Diametrical limit on the diameter to gain greater runout tolerance.

(OP)
Applicable standards BS8888 for this drawing

RE: Diametrical limit on the diameter to gain greater runout tolerance.

(OP)
This question from Manufacturer is 'The Bottom Dia 5.31/5.61 C/Bore is tied up to the Dia 6.0/6.3 long bore with 0.050 concentricity symbol. The feature is difficult to measure especially at the machine side. Long bore is also tied to O/D 0.025 concentricity. Requesting to lose some diametrical limit on the Dia 5.31/5.61 & Dia 6.0/6.3 diameters to gain greater runout tolerance'. Please find the attached previous picture.

RE: Diametrical limit on the diameter to gain greater runout tolerance.

My questions still standing:

You cannot gain greater runout tolerance because there is no runout tolerance specified on your drawing.

You cannot gain greater runout tolerance because runout is always specifies REGARDLESS OF FEATURE SIZE. No matter how many times you will change the dimeter, it will not affect the runout, even if it was specified on your drawing.

It looks like neither you or your "manufacturer" have no idea what you are talking about. Also. your manufacturer asks you to open the tolerance and you immediately comply. Do you know what tolerances are actually required for the part to work correctly?


RE: Diametrical limit on the diameter to gain greater runout tolerance.

Not enough information...
As noted, much depends on the tolerance stackup required for a functioning part/assembly. Doing as your powerpoint suggests will effectively loosen the tolerance between the smaller bore and whatever datum A is from Ø.075 to Ø.325. We don't know the tolerances involved relative to what is going into that bore, but if the worse case tolerances involved in the assembly will still allow it to function as designed, fine.

“Know the rules well, so you can break them effectively.”
-Dalai Lama XIV

RE: Diametrical limit on the diameter to gain greater runout tolerance.

... ignoring the fact that runout is still not indicated on the examples, just concentricity.

“Know the rules well, so you can break them effectively.”
-Dalai Lama XIV

RE: Diametrical limit on the diameter to gain greater runout tolerance.

Where is your datum feature A? or just a typo on the FCF.

Season

RE: Diametrical limit on the diameter to gain greater runout tolerance.

loka23,

Please re-write your question. We don't understand you.

Are you trying to open up a tolerance to make the thing more manufacturable? This is a design requirement, not a drafting procedure. The end user will tell you if this is a good idea or not.

--
JHG

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