Annoying sketcher problem 2

[treddie]

Hi.

I cannot find any resolution to this problem anywhere, and maybe someone here has a tip. All I want to do is draw a bunch of squares of equal size in Sketcher, using the Center Rectangle method. I have a bunch of centerlines set up so that I can snap each square to the center of where a square is supposed to go. But the squares end up snapping to dimensions that don't exist.

For instance, if I draw one square and constrain it to equal length sides and check that it is the correct size, then, if I start drawing more and more squares of the same size, they don't always END UP the same size even though I get the blue and red "L" symbols. Often, the squares try to snap to lengths that don't exist and they end up all wrong. I have tried limiting the amount of constraints to use, but have not found a combination that is not a headache. Also, since I am using the Center Rectangle method, I would think that Creo would understand that the square is symmetrical about the centerpoint. But Creo still insists on giving me 4 dimensions...side lengths, and distance of two of the sides from the centerpoint. Sometimes I get 8 dimensions because Creo sees each corner point of the square as independent of the others. Clearly, this has to do with what constraints I choose to use. But no combinations of constraints seem to be the headache-free, magic bullet.

The best solution I have found so far is to use the constraints:
Line up horizontally
Line up vertically
Midpoint

But then I have to supply separate dimensions for width and height of each square, which really defeats the purpose of equal-length constraints.

 

[looslib]

Are you setting the equal lengths with dimensions or using the equal constraint?


"Wildfires are dangerous, hard to control, and economically catastrophic."

Ben Loosli

 

[treddie]

I started drawing a rectangle and watched for the two "L" symbols to appear, to get my first square. Then, I dimensioned the square to the correct size. After that, whenever I would make a new square expecting it to snap to the dimensions of the first square, anything would happen. Even if I got a blue "L" symbol indicating a length of one of the sides matched that of the original, it wasn't always correct. If I use just the Equal and Midpoint constraints, It takes forever sometimes to get a new rectangle to become a perfect square matching that original. Again, sometimes I'll get a blue "L" matching some length from an alternate universe.

 

[kranmeste]

Hi,

I think that your problem can be that as a default Creo has ticked all "Sketcher Constraints Assumptions" boxes. This means that when you draw a new rectangle or any shape for that matter it will snap to all possible constraints.

If you go into File->Options->Sketcher, under "Sketcher Constraints Assumptions" you can select what constraint options shall be active. I've found that if you select "Line up horizontally", "Line up vertically", and "Equal Length" and deselect the rest it works rather ok.

I made center lines and 16 squares in about 90secs and i only need to adjust sidelength on 1 square and the rest will follow.

Hope this works for you.

Best Regards
Jakob Warncke

 

[treddie]

I think that your problem can be that as a default Creo has ticked all "Sketcher Constraints Assumptions" boxes.

That was one of the first things I checked. But out of all the combinations I tried, I don't think I tried your suggestion yet...Line up H, Line up V and Equal Length. So I just gave it a go and that actually worked really really good! THAT is a real timesaver.

Thank you very much Jakob. I figured there had to be SOME solution to this conundrum. There are so many combinations that sound right, and maybe only one or two that actually work for this.

Thanks again!

 

[mjcole]

In the good old days you had the option to turn off intent manager. I'm a big fan of no longer needint to Shift+RClick (MB3 click) to activate. Not sure if everyone knows this.
Right Button toggles ( )Active /Inactive constraints.
Tab Key cycles thru available detected constraints.

Imho Centerlines are buggy and overated. Try dimensioning one in a sketch and doing an angle based radial pattern. Your geometry will swing both ways. I wish Creo allowed Construction lines to be used as Centerlines for Mirror like in most other softwares.

The New Copy Paste Tool will allow what you want to be done. You can specify Distance in X,Y dirs & # of Copies
(#)Number in this case not (Pound, Hashtag)

In reference to Looslib's post
Equal Dimension Constraint was and still is one of my favourite enhancements in WF5.0 Reference Dimensions and Driving Dimensions may be toggled ad+Infinitum without loosing the Dim Name/ID

Has anyone else used the copy paste or move/rotate tool like I described. It would be nice if there was an instances option. No Time to post image now but can do later if anyone wants it.

In SolidWorks the Hide Dimensions icon only hides 3d Dimensions not all. But as of the 2013 Release SldWorksCorp added Conics

http://help.solidworks.com/2013/English/SolidWorks/sldworks/c_Conics.htm

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