surface symbol?

[emonje]

Just came about this drawing. Got two "R" like symbols. I haven't seen anything like this before. Looks like some kind of surface finish symbol. Can anyone please tell me what this means?
Thanks.

 

[MadMango]

I haven't seen those before. IF this is a cast part, perhaps it is a draft indicator? Also, I have no idea what the triangles mean either.

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of these Forums?

 

[PeterStock]

Due to company policies blocking flickr, I am unable to view the attachment. I have however, seen triangle used for surface finishes. The surface finish varied with the number of triangles. I do not know where to find a spec on what they mean.

I am thinking that where I saw them used, the meaning was given in the title block.

Peter Stockhausen
Senior Design Analyst (Checker)
Infotech Aerospace Services

http://www.infotechpr.net

 

[MadMango]

"Art without engineering is dreaming; Engineering without art is calculating."

Have you read faq731-376 to make the best use of these Forums?

 

[MintJulep]

I think the "R"s mean that machining is mandatory on those surfaces to achieve the final dimensions.

But my memory is hazy on where I might have seen a symbol like that before.

 

[emonje]

The triangles indeed indicate surface finish. But my problem is the "R" like symbols. Any idea which standard specifies these symbols?

 

[drawoh]

emonje,

I do not know what the squiggly Rs mean, either.

I observe that your drawing was done by hand, with a lettering template. The line work is fairly good with good distiction between the outlines and the dimension lines. The lettering template work is neat. The arrows are a little inconsistent. The two squigglies are fairly sloppy.

Is it possible someone doodled on the original?

Maybe it does not mean anything?

This has to be an old drawing. What would the standard have been, say, twenty years ago?

JHG

 

[321GO]

That's an old German DIN standard.

Search for "DIN 3141"

 

[321GO]

The "R" symbol looks like some sort of hybrid, not part of DIN 3141 to my knowledge.

 

[ctopher]

I have not seen this before either, but my guess is someone's hack job of showing that one surface is an external radius, the other is an internal radius.

Chris
SolidWorks 10 SP4.0
ctopher's home
SolidWorks Legion

 

[emonje]

The drawing is very old, at least 15 years. So far I haven't found anyone who knows about the standard the maker of the drawing was using.

The company that it came from is not sure but the latest info from them is like this: The part is a casting & the surfaces on which the two "R"s lay (inside of the bore & outside) should be machined as they need to assemble some sleeves on them.

The funny thing is that a senior guy from my company says that this wavy "R"s mean that surfaces should be left as cast. Can't say which standard but still he's sticking with his opinion.

Thanks.

 

[321GO]

Not sure if this is correct, but:

- an outwards open triangle means either cutting or deformation process

- a "wave" symbol also means either cutting or deformation process

The "R" like symbol looks like a hybrid of both i.e. open triangle "combined" with the "wave" symbol?!

Strange!

 

[321GO]

"So far I haven't found anyone who knows about the standard the maker of the drawing was using"

As i said... DIN 3141 or DIN 140!

 

[321GO]

Correction,

"a wave symbol also means either cutting or deformation process" - INCORRECT!

The wave would probably mean:
Surface NOT obtained by cutting or deformation. It is casted.

 

[MintJulep]

The company that it came from is not sure but the latest info from them is like this: The part is a casting & the surfaces on which the two "R"s lay (inside of the bore & outside) should be machined as they need to assemble some sleeves on them.

This is consistent with my guess.

 

[emonje]

I found an old document with a list of symbols for surface roughness. The Symbols are triangles (1 or many side by side), the number of triangles indicate degree of roughness (Ra). So the surface indicated by two triangles require finer machining than that with only one triangle. The triangle symbols in the document matches those in the drawing.
But I can't find anything like the "R"s. There's a wave symbol in the aforementioned list but it looks different from the "R" in the drawing. The wave, as 321GO said, indicates surface roughness typical for casting.

Thanks.

 

[jjengel]

While I haven't encountered this symbol before, whenever I have something like this pop up I'll check to see what's available in my Solid Edge libraries/menus. Under my surface finish menu I have triangles AND a tilde (squiggly line) that's looks darn similar to the Rs on the hand-drawn print. Both are from the JIS standard and apply to surafce finish. The number of triangles indicates different levels of surface finish. The tilde (~) indicates "Not a working surface".

With the different scripts (consider the way the nummber 1 is written in the US vs. some European countries) used around the globe to all indicate the same same thing, my mind starts to lean towards this being the answer...

I'm curious to know the answer to this one.

Jason

 

[jjengel]

As an addendum, a Google search of "JIS no working surfaces" yields several good results.

Try

http://www.vx.com/help/0725.htm

and follow the link to surface texture symbols.

Jason

 

[SeasonLee]

Its a JIS Standard, you may find out the "R" and triangular indication from the three pages attached.

Hope this help

SeasonLee

 

[321GO]

SeasonLee, the "R" is not part of the standard.

Why are you guys making this so difficult?