standard drawing scales
standard drawing scales
(OP)
Quick and easy one (I hope) which ASME standard says to only use 1:2, 1:1, 2:1 etc. I'm sure I've found it before but can't recal where.
I have a couple of prints with scales like 3:2 and one that seems to be about 1.25:1. I think they've done this in part to cram it onto a B size sheet rather than use something larger. At least one of the engineers in question is difficult to deal with so I want to make sure I'm on firm ground.
I'm not (I hope) just being pedantic but the drawings are pretty cramped and I want to use this as another factor to persuade them to use a larger sheet size.
Thanks,
Ken
I have a couple of prints with scales like 3:2 and one that seems to be about 1.25:1. I think they've done this in part to cram it onto a B size sheet rather than use something larger. At least one of the engineers in question is difficult to deal with so I want to make sure I'm on firm ground.
I'm not (I hope) just being pedantic but the drawings are pretty cramped and I want to use this as another factor to persuade them to use a larger sheet size.
Thanks,
Ken
KENAT, probably the least qualified checker you'll ever meet...





RE: standard drawing scales
Personally Will always draw on a sheet to big. I like the look of a small part on a big white background. But hey, that's art, not engineering
Wes C.
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RE: standard drawing scales
My personal standard is whether or not I have a drafting scale that can measure that scale. One of my metric scales does 1:125, so your 1.25:1 scale should work, assuming one of us got the numbers backward.
None of my scales handle 3:2 as far as I can tell, so I would not do that.
I strongly agree with 1:1 being the preferred scale.
JHG
RE: standard drawing scales
RE: standard drawing scales
I know I've been slapped for doing anything other than the 'standard' scales.
I'm all for 1:1 although a lot of the parts here are small and complex so 2:1 or more is very common/appropriate.
I also believe it's better to have a bigger sheet with lots of space than all crammed on a small sheet, to me it's not just art but a clearer drawing.
Just checked and the scale, at least on the hard copy I have, is about 1.21:1 (a 3.297 dimension is measured on the print at 4).
Anyway, probably wouldn't matter anyway as I've just been in a drawing where standards were pretty much thrown under the bus, I anticipate my lay off (as I'm a checker, no standards nothing to check to) sometime next week as part of lay-offs.
KENAT, probably the least qualified checker you'll ever meet...
RE: standard drawing scales
It states that the "preferred" scales are 1/1, 1/2, 1/4, 2/1, and 4/1.
As to which standard that was based on... ?
The only current reference that I could find is the one that Gary refers to, and it does not specify what scales to use.
RE: standard drawing scales
Full size: 1:1
Enlargment scales: 2:1, 5:1, 10:1, 20:1, 50:1
Reduction scales: 1:2, 1:5, 1:10, 1:20, 1:50, 1:100, 1:200, 1:500, 1:1000, 1:2000, 1:5000, 1:10000
Larger or smaller scales should be in multiples of 10 based on this series.
Being an ISO standard, it should be for metric dimensioned prints only.
We had a corporate standard for inch dimensioned drawings of: 1:1, 1:2, 1:4, 1:8, 1:16, 1:32, etc.
"Wildfires are dangerous, hard to control, and economically catastrophic."
Ben Loosli
RE: standard drawing scales
The scale 3/1 has never been acceptable.
Chris
SolidWorks 07 4.0/PDMWorks 07
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog
RE: standard drawing scales
That said at least some of my colleagues who've worked in more rigourous documentation environments do the same.
KENAT, probably the least qualified checker you'll ever meet...
RE: standard drawing scales
My guess is that may be going on with your designers. Maybe it's laziness, or maybe they just simply do not know, but with computer program... Garbage in = Garbage out & you must be smarter than the computer....
Wes C.
------------------------------
No trees were killed in the sending of this message, but a large number of electrons were terribly inconvenienced.
RE: standard drawing scales
I just checked and with ANSI (inch) formatting style selected my CAD gives 100:1, 80:1, 40:1 20:1, 10:1, 8:1, 4:1, 2:1, 1:1, 1:2, 1:4, 1:8, 1:10, 1:20, 1:40, 1:80, 1:100 as default options.
To get the scales they're getting I'm pretty sure you'd have to override the defaults.
KENAT, probably the least qualified checker you'll ever meet...
RE: standard drawing scales
RE: standard drawing scales
I wont ask you to guess which department these drawings are from!
KENAT, probably the least qualified checker you'll ever meet...
RE: standard drawing scales
"Wildfires are dangerous, hard to control, and economically catastrophic."
Ben Loosli
RE: standard drawing scales
KENAT, probably the least qualified checker you'll ever meet...
RE: standard drawing scales
Matt
CAD Engineer/ECN Analyst
Silicon Valley, CA
sw.fcsuper.com
Co-moderator of Solidworks Yahoo! Group
RE: standard drawing scales
;)
Chris
SolidWorks 07 4.0/PDMWorks 07
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog
RE: standard drawing scales
Fossils are considered valuable, because there ain't many of them around anymore, and with their demise goes a lot of valuable information.
RE: standard drawing scales
I was hoping that requiring them to use standard scales would also push them to using a larger sheet size so everything isn't crammed in.
By crammed in I mean crammed in to the point it's difficult to interpret.
KENAT, probably the least qualified checker you'll ever meet...
RE: standard drawing scales
;) "
Even my models of scale models? :)
RE: standard drawing scales
(It's only a model)
ssh!
RE: standard drawing scales
Who cares about your 1/1 model? It doesn't do much for a crammed up (or maybe I should use 2p's) B size draft file.
This is KENAT's problem and I know where he's coming from.
RE: standard drawing scales
RE: standard drawing scales
Fine, so tell them so. A cluttered print is a cluttered print, and adding sheets is not a no-no in your system, is it? I tend to avoid huge sheet sizes, because many shops will print them or photocopy them to reduced sizes (A or B), and everything then becomes un-readable, regardless of how artistically I placed my views and callouts.
"Who cares about your 1/1 model? It doesn't do much for a crammed up (or maybe I should use 2p's) B size draft file."
See above. A whacked-out scale may be just what is needed to make certain features stand out. And if not, I put detail views on sheet #2, in whatever scale the CAD system says they are in, but re-lable the scale as "2X" or whatever. Then I put a note on the drawing "DO NOT SCALE FROM PRINT". And put "NONE" in the scale block. Who cares, as long as the scale relationships between views is maintained. I agree, a crapped-up drawing is a crapped up drawing, but the scale doesn't matter for that. And if I ever catch some old fossil using a scale on my paper CAD drawing, with those notes above added, he and I will have a discussion.
RE: standard drawing scales
If you try to do it on a B you end up with 2 or more of the same view, each on different sheets, to fit all the dimensions. While occasionally unavoidable I think having the same view several times doesn't seem like good practice and going by some of the drawings I've seen it on it's almost always difficult to understand. I've seen I think it was 5 or 6 sheet B size drawing that looked like a bowl of spaggeti or a spiders web, so many lines. A colleague & I redrew it on E as I recall on a single sheet, that was a lot clearer.
I believe, and was taught, that fewer large sheets are preferabl to lots of small sheets. If the machine shop can't handle the larger prints then they shouldn't accept the job. However, to mitigate this we have our font size set to .15" rather than the minimum 3mm so it's pretty clear when reduced.
Anyway btrue, seems you'd side with them on this one, always useful to have the opposite view point. They will talk about machine shops not having large plotters etc.
The reason I wanted the scale to back me up is that they don't care how bad their drawings look and will argue any changes I request so I like to have as much amunition and make sure I'm correct before I approach them.
KENAT, probably the least qualified checker you'll ever meet...
RE: standard drawing scales
RE: standard drawing scales
Chris
SolidWorks 07 4.0/PDMWorks 07
AutoCAD 06
ctopher's home (updated 10-07-07)
ctopher's blog
RE: standard drawing scales
I have no arguement that more than one sheet is OK, however I think that one large sheet is better than multiple small sheets.
Glad I'm not the only one Ctopher, I was seriously starting to doubt myself.
When I said "how bad their drawings look" I meant as in regard to being difficult to read/incoherent/ambiguous. I did not mean that every drawing should be so beautiful you can frame it and put it on your wall!
KENAT, probably the least qualified checker you'll ever meet...
RE: standard drawing scales
As far as the scales we use, I have a very difficult time letting go of those that used to be "preferred", even though I realize that I don't really have a legimate reason for correcting drawings that use a "non-preferred" scale.
RE: standard drawing scales
Matt
CAD Engineer/ECN Analyst
Silicon Valley, CA
sw.fcsuper.com
Co-moderator of Solidworks Yahoo! Group
RE: standard drawing scales
A drawing that is ambiguous, difficult to read, or incoherent doesn't need any other argument from you. I spend way too much time cleaning up older prints around here, and know what you mean. I say again, there is nothing wrong with multipe representations of the same view, as long as you are careful not to "double dimension". We have a lot of small parts with lots of goofy details, and getting all of the details called out from one view would crowd the drawing with arrow heads and leader lines. When I do put details or aux. views on seperate sheets, I reference the new sheet on the view callout, and add a note such as "(FROM SHT. X)" on the view label. Not a requirement, but helps the reader.