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Standard for BOM Ballons>
- Thread starter cadfreak
- Start date
The top picture in your attachment.
Chris
SolidWorks 08 0.0/PDMWorks 08
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog
Chris
SolidWorks 08 0.0/PDMWorks 08
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog
The top one is what I have seen at several companies.
Chris
SolidWorks 08 0.0/PDMWorks 08
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog
Chris
SolidWorks 08 0.0/PDMWorks 08
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog
I've seen Bottom the most, or similar to the Middle example without the extra balloon. Quantities are defined in the BOM.
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CorBlimeyLimey
Mechanical
I've never seen the top version either, but then I've never worked for a company which needed to adhere to an externally recognised standard. If it is the official standard it doesn't really make sense to differentiate between items. The BOM states the quantity anyway.
MadMango,
Total quantities are defined on the BOM. The same part, especially a fastener, could be used in several places on the assembly. Often, I want to show how many screws are needed to attach a part. This can be hard to show on the drawing.
I have never seen it done the top way. I have seen the other two.
JHG
Total quantities are defined on the BOM. The same part, especially a fastener, could be used in several places on the assembly. Often, I want to show how many screws are needed to attach a part. This can be hard to show on the drawing.
I have never seen it done the top way. I have seen the other two.
JHG
I guess I should be more clear. Sorry.
The bottom is standard, calling out the qty next to the balloon. If another assy view or detail is called out on the dwg, the part can be called out again, but as reference illustrated in the top pic.
The middle pic should not be used.
Chris
SolidWorks 08 0.0/PDMWorks 08
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog
The bottom is standard, calling out the qty next to the balloon. If another assy view or detail is called out on the dwg, the part can be called out again, but as reference illustrated in the top pic.
The middle pic should not be used.
Chris
SolidWorks 08 0.0/PDMWorks 08
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog
CorBlimeyLimey
Mechanical
![[lol]](/data/assets/smilies/lol.gif "[lol] [lol]")
I find it strange that the one which most clearly denotes which component is which and where it is, is the one which shouldn't be used.Having said that I normally only balloon an item once and without the quantity.
powerhound
Mechanical
The way I've always done it is to use one balloon on one part and then have the quantities in the BOM list. I don't show the same balloon on an identical part elsewhere in the assembly unless there's a chance it could get goofed up. I've never seen a repeated part in parenthesis though.
Powerhound, GDTP T-0419
Production Supervisor
Inventor 2008
Mastercam X2
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II
Powerhound, GDTP T-0419
Production Supervisor
Inventor 2008
Mastercam X2
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II
I feel like the bottom one is the correct version, although now that I think about it, I don't think I've ever seen it done that way. I'm used to seeing the middle version.
V
Mechanical Engineer
"When I am working on a problem, I do not think of beauty, but when I've finished, if the solution is not beautiful, I know it is wrong."
- R. Buckminster Fuller
V
Mechanical Engineer
"When I am working on a problem, I do not think of beauty, but when I've finished, if the solution is not beautiful, I know it is wrong."
- R. Buckminster Fuller
aardvarkdw
Mechanical
I would not use the top one because the number in parenthesis could be confused as a reference dimension. The bottom one is the most correct method with respect to ASME Y14.5M-1994. The middle one, while not recommended, I have used on complex drawings to identify fasteners when there are several different types on the print and it is not easy to determine which is which.
David
David
Well I've seen the middle and bottom one, never the top one.
However, both the middle and the bottom one seem redundant to some extent. On the middle one doing it like this can get messy, especially if you extend it to fasteners, imagine how many balloons you'd end up with if you have a bunch of rivets or something... If there are only 2 item 3's on the entire assy then in the lower one the 2X seems to be duplicating the information in the Parts list which is a recipe for errors (although some CAD systems help with this) and can lead to a cluttered drawing.
Checker Ron & I went thru this a while back trying to determine what the ASME Y14.100 series said but it was difficult to determine an exlicit requirement as I recall. We ended up with the following in our DRM:
So say you use 6 screws on an assy. 4 to hold down a connector and 2 for a bracket. Based on the above I'd balloon one screw on the bracket and one on the connector. If it wasn't obvious that there were 2 on the bracket and 4 on the connector then I'd add a 2X & 4X respectively.
As I recall this was effectively what I did in the UK too though I don't recall it being formally defined.
KENAT, probably the least qualified checker you'll ever meet...
However, both the middle and the bottom one seem redundant to some extent. On the middle one doing it like this can get messy, especially if you extend it to fasteners, imagine how many balloons you'd end up with if you have a bunch of rivets or something... If there are only 2 item 3's on the entire assy then in the lower one the 2X seems to be duplicating the information in the Parts list which is a recipe for errors (although some CAD systems help with this) and can lead to a cluttered drawing.
Checker Ron & I went thru this a while back trying to determine what the ASME Y14.100 series said but it was difficult to determine an exlicit requirement as I recall. We ended up with the following in our DRM:
So say you use 6 screws on an assy. 4 to hold down a connector and 2 for a bracket. Based on the above I'd balloon one screw on the bracket and one on the connector. If it wasn't obvious that there were 2 on the bracket and 4 on the connector then I'd add a 2X & 4X respectively.
As I recall this was effectively what I did in the UK too though I don't recall it being formally defined.
KENAT, probably the least qualified checker you'll ever meet...
KENAT,
I have designed assemblies that have had over 100 occurrences of one screw. Needless to say, the screw was used in multiple places.
This is good design practise. If the assembler can put the whole system together with one to three different screws, then selecting screws from the kit is simple.
I have used the split balloon in SolidWorks. Systematically, I type in the quantity value, even if it is correct. The only way the quantity would have to change is if I change the mounting holes of something. The other way the BOM quantity would change is if I add another component that requires more screws.
Getting this all right is easier than it looks. On an assembly drawing of something complex, it makes things clearer. You cannot always get the view that clearly shows each component. Sometimes, things are too complicated for a clear, exploded view, and you have to go back to orthogonal and section views.
JHG
I have designed assemblies that have had over 100 occurrences of one screw. Needless to say, the screw was used in multiple places.
This is good design practise. If the assembler can put the whole system together with one to three different screws, then selecting screws from the kit is simple.
I have used the split balloon in SolidWorks. Systematically, I type in the quantity value, even if it is correct. The only way the quantity would have to change is if I change the mounting holes of something. The other way the BOM quantity would change is if I add another component that requires more screws.
Getting this all right is easier than it looks. On an assembly drawing of something complex, it makes things clearer. You cannot always get the view that clearly shows each component. Sometimes, things are too complicated for a clear, exploded view, and you have to go back to orthogonal and section views.
JHG
mechengdude
Mechanical
middle picture and bottom picture are both "correct". Never seen the top picture.
pierdesign
Industrial
I have not come across a published 'standard'.
I believe it depends on the intended use of the assembly drawing. Often assembly drawings, or portions thereof, are used by people not fluent in drafting convention.
Unfortunately, I disagree with ctopher; I've never seen your top example anywhere in the world on any language drawing. I have seen both your bottom two examples. In my opinion, most clear is a combination of both of them especially for orthographic view assebly drawings.
I believe it depends on the intended use of the assembly drawing. Often assembly drawings, or portions thereof, are used by people not fluent in drafting convention.
Unfortunately, I disagree with ctopher; I've never seen your top example anywhere in the world on any language drawing. I have seen both your bottom two examples. In my opinion, most clear is a combination of both of them especially for orthographic view assebly drawings.
I clarified myself at my third comment.
Chris
SolidWorks 08 0.0/PDMWorks 08
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog
Chris
SolidWorks 08 0.0/PDMWorks 08
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog
powerhound
Mechanical
That's actually kind of funny that you say you "clarified" yourself...as if to say that we misunderstood you and read the word "top" when we should have read the word "bottom" the first two times you typed it.
Sorry.. I couldn't resist...
Powerhound, GDTP T-0419
Production Supervisor
Inventor 2008
Mastercam X2
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II
Sorry.. I couldn't resist...
Powerhound, GDTP T-0419
Production Supervisor
Inventor 2008
Mastercam X2
Smartcam 11.1
SSG, U.S. Army
Taji, Iraq OIF II
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