Very quick question...on Bonus...

[brandnew1]

Attached pdf is based on the Y14.5-1982. i just want to make sure that bonus is allowed in terms of the .256/.261 hole.

Datum G (Hole) has the regardless of feature size, which i understand to mean no bonus even when the hole is larger than MMC. But the FCF connected to the small holes, if these holes go beyond MMC (.256) can i add the bonus to the .004? (please note that there is a maximum modifer condition symbol after the .004, its not shown in the pdf)

thank you

 

[drawoh]

brandnew1,

If there is an MMC condition attached to the Ø.261/.256 hole, you can add a bonus to the Ø.004 positional tolerance. This bonus would equal the as-measured hole diameter minus .256.

If Datum_G were at MMC, you would add that to the bonus too.

JHG

 

[pmarc]

Since there is no (M) or (L) modifier after tolerance value in positional FCF, no bonus is permissible. Dia .004 tolerance zone applies regardless of a size of each of 4 holes.

(S) modifier next to G datum reference within FCF has nothing to do with bonus tolerance value.

 

[pmarc]

Uups, sorry. I haven't noticed your remark in parentheses.
If (M) is placed after tolerance value inside FCF, then of course bonus is permissible. Its maximum value is .005, so maximum positional tolerance value can be dia. .009 when the hole is at its LMC.