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surface symbol?

surface symbol?

surface symbol?

(OP)
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.  

RE: surface symbol?

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.

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RE: surface symbol?

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
www.infotechpr.net

RE: surface symbol?

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.  

RE: surface symbol?

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

RE: surface symbol?

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

RE: surface symbol?

That's an old German DIN standard.

Search for "DIN 3141"

RE: surface symbol?

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

 

RE: surface symbol?

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

RE: surface symbol?

(OP)
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.  

RE: surface symbol?

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!




 

RE: surface symbol?

"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!

RE: surface symbol?

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.
 

RE: surface symbol?

Quote:

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.

RE: surface symbol?

(OP)
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.

RE: surface symbol?

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

 

RE: surface symbol?

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

RE: surface symbol?

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

Why are you guys making this so difficult?

 

RE: surface symbol?

(OP)
So the JIS says wavy symbol is for as cast surface. But the company that the drawing came from had used the old part and they are sure about necessity of machining on the particular surfaces.
& there's the problem, we are supposed to make the part. One of our senior guys doesn't want to do machining saying that wvay symbol means as cast (naturally to save cost). The customer wants them machined & says "R"s are different from this wavy symbol (but can't say exactly what they are or which standard they belong to).
May be in the end we will machine them, afterall the customer is always right.

RE: surface symbol?

If it may possibly be of a Japanese standard, I believe it is the old way of calling out a "smooth material" finish. According to our technical standard, it's not used anymore. I think that this is was do to a revision of JIS B 0031 standard. Many of the older drawings at our company have that symbol on them, as well as upside down triangle symbols (▽), though those aren't used anymore either.

RE: surface symbol?

Do you know anything about the maker of the drawing? e.g. his nationality

RE: surface symbol?

fsincox,

   We have not determined whether or not it follows standards.  We just do not know what the standard was.

   I observe further more that the lettering is neat enough that the drafter used a drafting machine to position his template.  The only exception is the one 10mm radius "R" which appears to be hand lettered.  

   I still think the two squiggly lines are nothing more than someone doodling on the original.  

               JHG

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