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tenbob
25th Apr 2012, 12:27 pm
Hi. I've been playing with the STRETCH command, but I can't get it to do what I want. Can anyone help?

I have a rectangle that is the correct width (X) but the wrong height (Y). How can I stretch it so the height is exactly 200? I think I know all the features of the stretch command. I can select the right nodes using a crossing polygon and stretch it an arbitrary amount with the cursor. I can also add an exact displacement to the size it was before.

The trouble is that all changes are based on the existing size. And it wasn't an exact size in the first place.

So how can I set the height to exactly 200? The SCALE command is no good as it scales X and Y the same amount.

The obvious work-around is to draw another rectangle the correct size on top of the old one. But that's an admission of failure. Am I missing something, or is there really no way to stretch something to an exact size?

MSasu
25th Apr 2012, 12:31 pm
I will draw a vertical line of 200 units starting from bottom-left corner of to-be-fixed rectangle; use later the top-left corner of rectangle and top end of line as from, respectively to points for STRETCH command.
This way will get a displacement equal with diffrence between line's length and height of rectangle.

Dadgad
25th Apr 2012, 12:43 pm
Mircea is right, there is no way to STRETCH (with that command) something to a target dimension from an indefinite size using direct data entry. Best to create a reference as suggested, assuming that you reject creating a brand new rectangle with direct data entry. It might not be an admission of failure to redraw it, it might be better characterized as a lucid moment. Wherever you go, there you are. How many times have I wasted stupid amounts of time trying to fix something which I could more quickly have redrawn? If you have dynamic input turned on you could draw it pretty darned fast. :wink:

Strix
25th Apr 2012, 12:53 pm
Is it possible to 'fix' a rectangle by editing its properties?

MSasu
25th Apr 2012, 01:04 pm
Once drawn, is recognized as an ordinary polyline – you can edit the Y coordinate of top points. This may be a reliable method in some cases, for sure.

mdbdesign
25th Apr 2012, 01:12 pm
I don't know if you using LT (Autocad LT not???) or full version.
Try this small utilities (full version only) by kojacek.

Dadgad
25th Apr 2012, 01:37 pm
I should think that doing something as efficiently as possible would by definition trump an ill-conceived preconception of a clever way to do it, resulting in roundabout ways to further decrease one's efficiency, no? If it is not what you want, then fix it in the easiest way possible. :beer:

Strix
25th Apr 2012, 01:42 pm
Agreed - I'd redraw the thing (with input values), but I was exploring the functionality of AutoCAD

Is it possible to assoc dimension it, then edit the dims?

sevdo2000
25th Apr 2012, 01:47 pm
You can use "from", from the right click submenu, holding down shift.
Select base point of stretch, then click rigth mouse button with holding down shift and select "from", select opposite sight of rectagle, use tracking to select direction, then type size and hit "enter".

Dadgad
25th Apr 2012, 02:26 pm
Agreed - I'd redraw the thing (with input values), but I was exploring the functionality of AutoCAD

Is it possible to assoc dimension it, then edit the dims?

A commendable aspiration, and an interesting albeit convoluted bit of conjecture for such a mundane and momentary task. :| I wouldn't know, don't do ASSOCIATIVE, maybe? :beer:

BIGAL
26th Apr 2012, 04:04 am
Why not use constraints thats what there for just enter x & y box drawn to that size can change at any time ht can be a fixed ratio of length etc.

tenbob
26th Apr 2012, 10:13 am
Wow. Thanks for the tremendous response.

I particularly liked Dadgad's suggestion to go straight for the obvious solution. Just redraw it the correct size instead of wasting valuable time looking for an elegant way to modify what was there.

But sevdo2000 has shown me the ideal way to do it using "snap from". Until today I didn't really understand this feature. From now on I plan to use it all the time.

To summarise what I found, the "snap from" feature allows you to enter a point that is an exact distance from some other known point. There's not much documentation around on it that's easy to understand. This is a brief explanation.

Any time Autocad wants you to enter a point you can use the "snap from" osnap. Select it by typing FRO or using the shift-right-click menu. You can then select a base point (using any other appropriate osnaps) and an offset. To enter the offset you must use the @20,30 format. If you use 20,30 it will ignore your base point and go to the absolute coordinates instead. Or you can use direct distance entry by moving the cursor in the right direction and typing a single number.

Thanks for your help everybody.

Strix
26th Apr 2012, 12:36 pm
Glad you found a solution that suits you, AND learned something :)

THAT'S why it's always worth discussing other options, even if the OP is answered in the very next post :thumbsup:

dbroada
26th Apr 2012, 12:58 pm
Why not use constraints thats what there for just enter x & y box drawn to that size can change at any time ht can be a fixed ratio of length etc.as the OP hasn't said what version he has he may not have constraints (says somebody looking at them for the first time).

troggarf
26th Apr 2012, 01:36 pm
Regarding the issue of how to use the STRETCH command remember this:
You use a "crossing window" so anything completely within the crossing window will be moved during the stretch command and anything that the window crosses will be stretched.

Below are 2 links that demonstrate this with plenty of pictures to help clarify:

STRETCH orthogonal (straight up or down - aligned with the UCS
http://autocadtips.wordpress.com/2011/06/06/how-to-use-stretch/

STRETCH at an angle (not aligned with the UCS)
http://autocadtips.wordpress.com/2011/09/26/how-to-use-stretch-with-an-angle/

~Greg

BIGAL
27th Apr 2012, 03:43 am
Dbroada constraints came out of inventor a long time ago the idea being rough draw something then enter true measurements plus rules and auto redrawn correct, shapes like rectangs, base plates perfect for constraints. base plate LxW 4 holes, holes are 1/4 dia from edge, corner radius 1/2 hole size change 1 hole dia all change and so on .

dbroada
27th Apr 2012, 08:40 am
Dbroada constraints came out of inventor a long time ago
I'm not disputing that but they didn't get to AutoCAD until after 2008 (my previous release). Since the OP is using LT and doesn't say what version there is every chance that he hasn't got them yet. I've had a look at them this week and they look brilliant - if I can find a use.