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Mark Meredith
01-07-2017, 01:50 PM
In modeling my Super Chipmunk I now have a fairly deep tree structure of assemblies within assemblies. I've found 2 curious issues working with the highest level assembly:

1. I can't rotate it around on the screen with the trackball and wheel like I can when I open the lower level assemblies or parts. It rotates around weird, inconsistent axes (like way out a wingtip as if flying 8s on pylons!). So I can't easily move it around to different view angles except by snapping it to a specific x, y or z.

I tried creating a coordinate system centered at the approximate CG, thinking I may be able to spin it around that point, but it did not change anything.

2. Assemblies with moving parts can only move at the level where they were mated. They're frozen at any higher level.

Any ideas? Neither of these are huge deals except it seems like I should be able to fix them with secret clicks. Thanks!
Mark

lathropdad
01-07-2017, 02:20 PM
Item 2 is just the way SW works. To get around this problem, I sometimes will suppress the ball of a rod end in one assembly and then in a higher level have that ball as a part of the higher level assembly and use the ball as a mate in the higher level assembly. That way I can see objects move.

Item one may be an issue with your graphics card and the available memory SW has to work with as you manipulate a drawing. On my older computers, with less memory, I find that when I manipulate an object, the drawing changes to a bunch of rectangular blocks that correspond to the elements of the drawing. When I quit moving the object, it will redraw as the assembly I am working with.

I use W7 pro. I have not changed to W10. When I talk with the tech guys at my SW reseller, they are not encouraging me to change.

Mark Meredith
01-07-2017, 03:48 PM
Thanks. I tried suppressing a whole ton of mates involved in movement of 4 parts relative to each other (a main strut and links). When I then tried to unsuppress them at the top assembly, SWx asked me to replace the mates one at a time. Not worth it. Lesson learned: anything I want to see move at the top level, build the mates at that level!

cwilliamrose
01-07-2017, 04:26 PM
Mark,

1) Can't help you much here since I use a Space Explorer to manipulate the model on screen but generally the rotation center is the origin (I think). With the Space Explorer you can select any rotation point or axis, not sure how to do that with a mouse or trackball.

2) Right click on the stuck sub-assembly and select 'Component Properties'. Toward the bottom right corner of the dialog is a property named "Solve As'. That setting defaults to 'Rigid', change it to 'Flexible' so the sub-assembly will have all its freedoms of motion. Don't do this unless you really need that functionality -- it costs you resources to make an assembly 'Flexible'.

You can put things in your feature tree in folders to organize them and shorten the list. I do this often for hardware and also for related items like the elevator control system or trim system components in my Pitts model.

Mark Meredith
01-07-2017, 09:42 PM
That setting defaults to 'Rigid', change it to 'Flexible' so the sub-assembly will have all its freedoms of motion.

Bam! That resolved it. I figured there was a button I wasn’t finding. And yes, SWx immediately said I was running low on resources. So I know how to do it and can turn it on when needed.

Good idea on putting stuff into folders. Building parts within assemblies went a long way toward organizing a long tree (and making it much easier to modify) but there is still lots of disorderly junk that needs to be swept up and put somewhere. Sort of like my hangar.:rollseyes:
Thanks! Mark

cwilliamrose
01-08-2017, 11:13 AM
Mark,

My feature tree looks like this for the Pitts assembly;

6032
I haven't cleaned it up lately so it could be a bit neater but you get the idea. With folders you can hide or suppress them which can come in handy sometimes because it's easier than deal with the individual components separately.