Have you seen this symbol?

[BANDY]

Have anyone seen this symbol? I am talking about that M in the rectangle. What is that symbol represent? I am trying to find it in the ASME book I can't find this one. See attached B/P.

[John Riggins]

I don't think it's an ASME symbol.
Perhaps something specific to your customer?

[knati]

It's a customer AQL requirement and stands for Major Characteristic. A characteristic, other than critical, which if defective could result in product failure on which the defective part is installed. Check your customer AQL for their specific definition. Hope that helps.

[AuRules]

When I worked in the auto world (now aerospace) the letters in the triangle and/or diamonds meant that the customer wanted to hold this dimension with either hard gaging 100% or controlled with SPC. It's was the customers critical char. the needed to be correct to mate to another part.

[John Kingston]

I agree with the Major Characteristic.

[#2#]

It's a customer AQL requirement and stands for Major Characteristic. A characteristic, other than critical, which if defective could result in product failure on which the defective part is installed. Check your customer AQL for their specific definition. Hope that helps.

Agreement.

Except I must point out IMHO a characteristic which if defective could result in product failure would to me be the definition of a critical characteristic.

[Wes Cisco]

Agreement.

Except I must point out IMHO a characteristic which if defective could result in product failure would to me be the definition of a critical characteristic.

Goodluck, This is your last warning! If you continue to make sense we will stop the planet and throw you off!
-the mgmt.

[#2#]

Goodluck, This is your last warning! If you continue to make sense we will stop the planet and throw you off!
-the mgmt.

Oh boy! I've always wanted to be a space traveller!




Can you wait long enough for me to go get my towel?

[John Kingston]

Oh boy! I've always wanted to be a space traveller!




Can you wait long enough for me to go get my towel?

You don't have it with you...... Be careful, the Bugblatter Beast of Trall may get you!

THGTTG was on last night. Unfortunately I missed it.

[dccfreak]

The major characteristics controlled by a diamond encased M, is indeed a major characteristic. If applied properly according to the AIAG PPAP regulations, the diamond shape states that this feature is a safety characteristic and must be monitored, but, it is not a critical feature and does not have to exceed a 1.33 Cpk. They are basically pointing it out so that they can insure that this feature is addressed on the Control Plan of whomever runs the part.

Auto ppl do this all the time. Basically it's important enough for you to monitor, but, it doesn't have to be controlled by a 2/3 tolerance control limit. Sometimes vendors don't always feel certain things are important to their process so they overlook certain dimensions that are important to the customer on their control plans so this way the customer can point it out. Hey! We want you to pay attention to this one! That's all it is.

El Freak

[Perry Fisher]

Auto ppl do this all the time. Basically it's important enough for you to monitor, but, it doesn't have to be controlled by a 2/3 tolerance control limit.

If they want a 2/3 tolerance control limit why don't they dimension it that way?

I have a customer wanting us to "dial in" dimensionally acceptable parts closer than the print tolerance. Where is "dial in" addressed in standards?

"Yeah, your parts meet my print but can you get them closer?"

[Underspec]

I would agee it's a Major/Minor Characteristic. My prints sometimes come with Diamond shaped symbols which are referred to in the "Notes" section as Major/Minor characteristics.

[#2#]

If applied properly according to the AIAG PPAP regulations, the diamond shape states that this feature is a safety characteristic and must be monitored, but, it is not a critical feature and does not have to exceed a 1.33 Cpk.

I'm going to do it again Wes...





So a safety characteristic is NOT a critical feature?!?




(rocking back and forth) Cabin in the woods, cabin in the woods...

[\v/inston]

If they want a 2/3 tolerance control limit why don't they dimension it that way?

I have a customer wanting us to "dial in" dimensionally acceptable parts closer than the print tolerance. Where is "dial in" addressed in standards?

"Yeah, your parts meet my print but can you get them closer?"

2/3 tol meaning its not going to meet capability unless you are within two turds of the tolerance.

[Perry Fisher]

2/3 tol meaning its not going to meet capability unless you are within two turds of the tolerance.

I understand meeting capability initially. I don't understand wanting production parts held closer than print tolerance.

Some of the parts we run those turds will have to be small rabbit turds.