Are machining marks required in all views in a drawing? 1

[renasis]

Hello,

I have a part that is machined on a surface. That surface is shown in two views in the drawing, front and side. Is is necessary that I have a machining mark on both surfaces or is one sufficient? Is there a standard that specifies whether the machining mark needs to be in all views?

Thanks,

-renasis

 

[CorBlimeyLimey]

You only need a 'machining mark' if you are conforming to a standard. Which are you wanting to conform to?

 

[renasis]

ASTM Y14.5

 

[PeterStock]

I assume you mean ASME Y14.5-1994 which I believe is the most commonly used version today, 2009 is the latest. There is nothing in the standard about finish marks. There is a reference to another standard:

ANSI/ASME B46.1-1985, Surface Texture (Surface Roughness, Waviness, and Lay)

I do not have access to that standard at the moment, but I think a duplicate finish mark with a finish value would be subject to error when a change is made. As such I would avoid adding extra finish marks where possible. If neccessary for clarity, I think it would not be that much of a problem if you add extra finish marks as long as you confirm that the values are consistant.

Peter Stockhausen
Senior Design Analyst (Checker)
Infotech Aerospace Services

http://www.infotechpr.net

 

[ctopher]

What exactly is meant by showing a 'machining mark'?

Chris
SolidWorks 09, CATIA V5
ctopher's home
SolidWorks Legion

 

[JMarv]

What exactly is meant by showing a 'machining mark'?

A specific surface finish symbol that denotes "machining required." (There's a picture of each symbol and what they mean in the SW help under "Surface Finish PropertyManager").

Joe
SW Office 2008 SP5.0
P4 3.0Ghz 3GB
ATI FireGL X1

 

[FrenchCAD]

I would second Peter and say that it is only required once except for clarity purposes

Cyril Guichard
Defense Program Manager
Belgium

 

[renasis]

To all,

Thanks for the replies. I am going to play devil's advocate. I found a book that I refer to occasionally. It indicated that the finish mark is shown only on the edge view of a finished suface and is repeated in any other view in which the surface appears as a line, even if the line is a hidden line. Reference the excerpt here:

http://www.google.com/books?id=eMqV...epage&q=technical drawing finish marks&f=true

I searched online and found another comment that supports this here:

http://www.google.com/books?id=BjJi...awing+finish+mark&lr=&ei=5-aBSqCNJYbMM-mKueIK

So, are these books wrong? Does anyone have the ANSI/ASME B46.1-1985, Surface Texture (Surface Roughness, Waviness, and Lay) standard?

Thanks,

-renasis

 

[NomLaser]

I would think that the hidden line reference would be confusing. Are you referring to the line or the surface that the line just happens to be behind? Typically you don't reference hidden lines so why would you put a surface finish note on one?

 

[ewh]

While I have great respect for the work of French and Veirck (having been taught from their books myself), your second example is from a book printed in 1960.
Neither of those books are in any way to be considered standards, but only teaching tools. Look into the relevant standards to answer your question if you want to be sure of the correct answer.

"Good to know you got shoes to wear when you find the floor." - [small]Robert Hunter[/small]

 

[KENAT]

I'd consider it similar to dual dimensioning, which is a no-no. So I'd only put it once. If you really want to put it again I'd make it reference. That way if it changes in future but one of the reference ones is missed, at least the user knows which is the 'driving' requirement.

KENAT,

Have you reminded yourself of faq731-376 recently, or taken a look at posting policies:

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

What is Engineering anyway: faq1088-1484

 

[renasis]

I was able to get a copy of ANSI/ASME B46.1-1985, Surface Texture (Surface Roughness, Waviness, and Lay), it has plenty of information on how to specify the surface texture, but I wasn't able to find information on whether it should be specified in multiple views.

I looked on Google books again and found a couple of books indicted that the surface symbol should only be placed once, in one view, preferably on the view that has a dimension to the feature. By placing the symbol twice, it would be as Kenat said, similar to a dual dimension(which would be redundant).

Thanks for all your replies.

 

[MartinSr00]

For mechanical drawings, the finish marks, or any requirement should be in one place. Putting them in two places can result in conflicting requirements if the finish marks in both views don't agree, perhaps because of a revision. In short, expressing a requirement multiple times on the same drawing will almost certainly result in configuration control down the line.