Assembly Creation Questions

[ShopRat]

I need to create an assembly consisting of a welded tubular frame with panels and gages, etc. I started building the frame in a file called "frame". Basically rectangular shaped with corner joints mitered, welded, and ground flush. I created the front, back, left end, right end, and cross brace, all as new parts in the same file, and assembled them using mate and flush constraints. I created a scene with explosion factor, but the only part that moved is the cross member. Any suggestions?

Should I create each of the component parts of the frame (there are more pieces to be added) in seperate files? How do I constrain the parts in the assembly so that if the size of one part changes, the affected parts will change with it? For example, lets say the length of the side changes from 30 units to 20 units, then the cross member must also change by 10 units and maintain face to face mating relationship with the front and back rails.

Mike Butts
michaelb@sccoast.net

We are small, and offer CNC machining, Fabrication, reverse engineering, AutoCAD generated documentation in 2D or Solid Models. We look for the challenges that others pass up, working with numerous materials such as Aluminum, Stainless Steel, Inconel, Ha

 

[ShopRat]

Fawkes,

Thank you for the very useful information. I am still trying to get a grasp on how to build my model so that it will explode properly. Until then, Tweaks and trails for now. The spreadsheet info was very interesting, but seems like alot to do to make a simple change. Using the equations will work nicely for me.
Mike Butts
michaelb@sccoast.net

 

[Adrian2]

Dear Mike;

I had the same problem producing exploded views of industrial brakes. After reading the desktop training material I discovered you must avoid mate plane/plane and insert mates if you are going to be making exploded views that explode correctly on the first try.

According to the manual, you should use flush line and line/line wherever possible. Try to constrain without suing planes. This worked for me. I still had to use the odd tweak but no where near as many as when I started.

Regards Adrian

 

[ShopRat]

Hi Adrian,

As soon as I read your message I jumped into my drawing and checked my constraints. Sure enough I had mate pl/pl listed on just about all the pieces. I deleted all of them but still had no luck exploding. Must be something else wrong, I'll have to dig deeper. I did a quick model of two parts with a mate ln/ln and created a scene with explosion factor of 4, and activated that scene. No exploded parts. If I pick the edit constraint icon and enter the value in the dialog box, update the scene and it will then offset the amount entered. Perhaps I have some parameter set incorrectly?
Mike Butts
michaelb@sccoast.net

 

[Adrian2]

Dear Mike;

Do you know that there are two seperate explosion factors.

The explosion factor for the entire assembly is accesed through Assembly, Exploded Views, Scene Explosion Factor.

The explosion factor for the individual part is accesible by right clicking the part in the browser.

If that is of no help examine system variable AMSCENEUPDATE
It is supposed to be set to 1 for auto update, If it is 0, exploded views wont update without pressing the scene update at the bottom of the browser.

Also I am mistaken in my advice re the constraining of planes, my manual reads as follows;

If no constraints were applied, parts will not move, no matter what explosion factor is applied

Only the insert constraint and Mate constraints that involve planes will move apart when an explode factor is applied.

If you do not want a particular pair of constrained parts to move apart, consider using Flush instead of Mate plane-plane, Flush plus Mate line-line instead of Insert and Angle line-plane instead of Mate line-plane.

Sorry to send you on a wild goose chase, I hope this clears up your problem. Please let me know.

Regards Adrian

 

[ShopRat]

Dear Adrian,

Your information was most helpful. I used the mate pl/pl on the faces of the mitered corners, and the parts explode nicely. Thanks again.

Mike
Mike Butts
michaelb@sccoast.net