Negative dimensions: why not?

Maybe newer SW can do this (newer than 2001Plus) but for some reason I
doubt it.
I want the ability to change any dimension to a negative number (or even
zero, for that matter).
Why is this useful? In my part I have a rectangular cut with a centerline
that is dimensioned to a plane in the middle of the part. If I want to
slide the cut to the other side of the center plane I have to edit the
sketch rather than just setting the dimension to -3. Likewise if I need to
locate the cut in the center I again have to edit the sketch.
Yes, I could change the dimensioning scheme to reference one of the outside
edges rather than the center plane but then I may have to sacrifice other
things (like design intent).
It just seems like it should be such a simple thing to add this.
Or maybe my ProE background has twisted me.
Joel Moore
Reply to
Joel Moore
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You know what? This appears to be a tired issue. After searching Google (after posting, of course) I realize now this has been debated to death. SW is obviously never going to enable this ability.
Never mind.
Joel Moore
Reply to
Joel Moore
It was one of the very first things I noticed (next too disjointed bodies) with I first started using with SW. So, I totally agree but it is not to be in SW. Why?,... who the hell knows!? Or maybe it will change if more users request it and if the competition markets that SW can not.
The reality, as you most likely understand, is once you've used it, it becomes indispensable.
Reply to
Paul Salvador
Hi Joel,
I also find it strange that we can flip the sense of things when mating and using offset from surface, but cannot do this with sketche dimensions.
Along the same lines, is seem absolutely insane to not be using signed coordintes with ordinate dimensions. I have had many cases when my zero point (ok not always the ouside of the block) made a hole that was .0027" from zero? Buy which way you ask? I don't know, lets just guess, the perforator can flex a bit and hopefully not break . . .
Renee Descartes must be rally pissed that these folks have used only HALF of his grand co-ordinte system by presuming that nobody would ever need to use a negative value. But hey, you cah always manually add a negative in front of the dimension, but lets hope you don't change anything to make it move across the line . . .
Enjoy -
I agree
Reply to
Sean-Michael Adams
"Sean-Michael Adams" a écrit dans le message de news:
René is a "he" ;=)))
Reply to
Jean Marc BRUN
I'm with you, this would be such a nice addition to SWX. I have been begging for it since 98+ to no avail. I used to run ProE and could give dimensions negative values. (ProE handled them kind of strangely) But one situation I run into a lot is angular values. What a pain it is to have to edit the mate to get something to move from above horizontal to below.
Dear Solidworks, Instead of fancy schmancy new features that seem marginally useful (like shadows and skins for the feature manager) and concentrate on something boring but usefull like negative values.
Just venting a little
Reply to
Bryan Player (Sean-Michael Adams) wrote in news:
Actually, it's only 1/8 (in 3D space).
Reply to
Joel Moore
And it's really strange that you HAVE to use negative dimensions in section views!
Unfortunately, it seems that the folks at SolidWorks have their heads so far up their asses on negative dimensions in any other place that it will never get changed. What a waste!
Jerry Steiger Tripod Data Systems
Reply to
Jerry Steiger
Now you've done it. Your VAR has just out you on their 'black list' and SolidWorks has put your email address on a filter that sends them right to the trashcan.
Reply to
Jeff Norfolk
They don't provide for opposite directions everywhere and they don't do it in a consistent fashion where they do.
As a very simple example, suppose you are putting a hole in a plate and you want it 3 inches from the center line. You put a circle in a sketch and dimension it from a center line. Now you decide to put the hole on the other side. It would be nice to just enter a minus sign in front of the 3, but you can't do that. Suppose you have used that hole location dimension in your drawing. If you delete the dimension, you have to reinsert it in your drawing. So you have to set it to driven, drag it to the other side, then redimension it at 3 inches. Wouldn't it be a lot easier if you could put in negative numbers?
Jerry Steiger
Reply to
Jerry Steiger
Does anyone remember that there was a version of SW that allowed you to change the direction of dimensions? Ever wonder why the "Modify" box is long enough to have an extra button on it? I think it was removed in 97+ because it didn't work right. whatever.
If you use "Override dims on drag", you can get dimensions to go a different direction. It's not a good solution, but it might be better than deleting and recreating dimensions.
Joel Moore wrote in news:Xns93CA903D06D32asdsadfgasdgadsa@
Reply to
matt points out
I agree this is not ideal, but in the absence of ability to use negative numbers, it's damn useful. So useful that I find it irritating that the command is so inaccessible and there are no status indicators. My user group voted for and submitted an ER for a toolbar, perhaps living in the status bar at the bottom of the screen, with different coloured traffic lights for the different sketch settings, identified by tooltips, and with the ability to toggle them on and off by double clicking on them.
Given that some of these settings are powerful and can screw with your sketch, you don't want to toggle them on accidentally. I hit on the short term solution (which I use for "Override dims on drag",) of assigning a multiple key shortcut (I use Ctrl-Alt-O), on the principle that I am never going to accidentally invoke something which requires either both hands or the technique of a concert pianist. It is testimony to how much I use this that I find I can always recall the shortcut.
The way I use it for reversing the sense of dimensions is to clear my mind of distractions, invoke the shortcut, drag the dimensions across, reinvoke the shortcut IMMEDIATELY to cancel it (even if the phone starts ringing), then edit the dimensions. If a target dimension is critical, I might type the desired figure into the text comment area of that dimension's dialog box before I make the change.
If there's only one dimension to change, it may be more practical to use the "Driven"/"Driving" toggle recently added to the RMB context menu.
Reply to
Andrew Troup
What do you expect from a program that only finally decided to make a global XYZ coordinate axis triad an option to actually be seen now in their *last* major upgrade? Never saw the (user's) need to use it before?
I gave up before SW2003, but now is there only one point allowed per X, Y, and Z coordinate point? It seems like I had problems with SW trying to call the same point by 2 different X, Y, and Z coordinates...or maybe that was more related to my next comment.
And what do you expect from a program that allows a separate origin from part, to sketch, to sketch?
Frustrated Non-SW user at work (because of the hangups), Ken
Reply to
Ken Bolen
"JustMe" wrote in news:
You're only talking about assembly mates and feature depths/heights. There is no "opposite direction" concept for sketch dimensions.
If you haven't worked in another CAD system that supports this (i.e. ProE) then I suppose you wouldn't understand the usefulness of it.
Reply to
Joel Moore
Reply to
Andrew Troup

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