Sheet Metal Gauge Callouts in Drawings 2

[wblanchard]

Does anyone know if there is a standard for calling out sheet metal gauge thickness? Currently we are calling out the dimentional size followed by the gauge callout in parenthasis in the drawing notes Ex. Material: Aluminum .091 (11 Gage). Then in the main view we callout the thickness as a reference dimention.

Thanks

 

[mcgyvr]

Sheet metal gauge is already a standard..
In reality simply calling out the gauge alone is 100% acceptable and all that is needed.

 

[wblanchard]

Thanks mcgyver. That was where I was leaning but there had been some debate about it here.

 

[berkshire]

Specify whose gage you are using. There are different gages for different metals. Also gage numbers are different in different countries. Adding the decimal dimension is always good practice, then there is no confusion as to what you want.

http://www.engineersedge.com/gauge.htm

B.E.

 

[wblanchard]

berkshire Good point. I work for a product design company and our clients do occasionally have their finished designs manufactured overseas.

 

[MintJulep]

Add a note stating what standard the gage callouts reference, and that tolerances for sheet thickness are to that standard, and not the drawing title block.

 

[drawoh]

wblanchard,

I recommend not calling out the sheet metal guage. Call out the thickness, and apply a tolerance. In most cases, you can design sheet metal parts such that the thickness tolerance is not critical.

Sheet metal fabricators know their sheet metal guages. They can read your numbers, and select the correct sheet from stock.

Your inspectors may or may not know sheet metal guages. It is irrelevant to them. They need to know whether to accept or reject the part they are inspecting.

Tell your shop you need .091±.015. Let them figure out how to do it. You can provide the gauge as a reference note.

JHG

 

[wblanchard]

Thanks to everyone who responded.

 

[SteveMartin]

If your drawings reference Y14.5 one of the fundamental rules is that materials manufactured to gage or code numbers are specified by linear dimension. The gage or code number (in parentheses) is optional.

 

[KENAT]

As Steve says, dimension the actual thickness, at least per ASME Y14.5M-1994 1.4(h). You can say 'STOCK' after the dim to call up standard sheet tols.

Having discussed it at great length with several very experienced checkers, we typically dimension the actual/nominal thickness, usually followed by 'STOCK' rather than directly toleranced and will normally add the gauge in parenthesis in the material description.

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​