Assembly Question 1

[gobigracing]

Ok I trying to design and model a big project in solid works. To start with I know a few things.

Where and how it will mount to an existing place on the truck. And where the wheels will touch. I need to design everything in between. I figured I should do this is Assembly mode so that everything has relations with each other so if i change like the length or height it will change to middle components by itself.

Basically what I wanted to do is built the front and throw down so basic wheel and then build in between. Is this the way I should be doing this. Or is there a better way. Can you add Assembly relations later. Note: I don't mean mates and mean changing the part.

Also if this is the way to do this then any tips or tutorials. If not the how should I be doing this.

 

[JMirisola]

Check out top-down design. Basically, you want to be able to drive the middle assembly if you change what it's mated to, right?
Part of the problem you may run into is the number of components in the sub-assembly you'll want to control. You need to watch out for circular references, among other things. Too many "links" can also cause performance issues.

Jeff Mirisola, CSWP, Certified DriveWorks AE
CAD Administrator, Ultimate Survival Technologies
My Blog

 

[EdDanzer]

You did not define large, under 300 components, over 1000 components, or over 5000 components.

Having designed and built many 300 to 1500 components assemblies I suggest using many subassemblies. In many cases doing a basic layout sketch of fixed areas and using this as the template for all other parts and assemblies by doing a file save as or copy and paste. Try not to have any external references. When the next version of SoldWorks is installed there will be update problems with older assembles and drawing pages.

Ed Danzer

http://www.danzcoinc.com

http://www.dehyds.com

 

[gobigracing]

sorry it will be about 300. OK I try them both and see. Thanks!

 

[bvanhiel]

I don't like using assemblies for managing external links. Another technique that I would suggest trying is creating a "master model". The master is a layout part that contains the mounting positions and perhaps some other layout geometry. You can then add it to your dependent parts with "insert part". With 2008 you can pass sketches through, so the layout part can be very lightweight.

-b

 

[gobigracing]

bvanhiel - This sounds like a good way to do it. How do I use the master model to add references to the parts. Is is like using an external reference outside the part or something. I'm not exactly sure how to do this outside of assembly.

 

[bvanhiel]

Insert the master model into your part under Insert->Part. You will have an external reference to the master model. You can pick to show solids, datums, surfs and/or sketches.

I think this method is cleaner since you don't have the additional layer of assembly references, and it's clear which way the relationship is supposed to go (all parts reference the master).

This technique was limited before SW08, as you could only show solids, surfs, and datums. The ability to show sketches really lets you take advantage of the technique.

-b

 

[gobigracing]

I have another question. I want to put a rod end into my Assembly. Been messing with it for awhile but I can figure out how to make the rod end rotate around the ball. Any advice on that.

I include the CAD file I got from the manufacturer.

 

[handleman]

In the part file for the ball, create a sketch and add a point at the center of the ball. In either the assembly or the part file for one of the other components, create another sketch and add a point for the center of rotation. Add a coincident mate between the two points.

-handleman, CSWP (The new, easy test)

 

[gobigracing]

thanks a lot everyone. I used all of your advice and it worked. Also learned more about other solidworks features in the process. Thanks Again!

 

[gobigracing]

Ok so I made a master model. Or more a master 3d sketch and inserted it. Then built my parts off of it. All is well until I try to update the master model and none of the parts change but the master model does. All of my relations to the master model are still there but don't engage so to speak. But if I delete them and add them again they work. I used the rebuild and nothing happened. Any idea why it wont work.

 

[bvanhiel]

Did you regen the parts and not just the master? I would also try a Cntrl-Q regen to make sure it regens from the beginning.

-b

 

[gobigracing]

yes I did both. The master would update in the new part but it was like my references to it were none there. Then if I deleted the reference measurements and re added them they worked.

I try it some more and see what I can do.

 

[bvanhiel]

Not sure what to suggest, as I've had no problems. perhaps one of the guru's on here knows if the "no external references" setting applies.

-b

 

[gobigracing]

Weird, I checked everything over and nothing. Then I used the control Q and all of my models updated perfectly. Thanks a lot man. This is going to make my assemblies way more efficient. Especially since a lot of the parts with change totally but still have the same mounting locations.


Thanks again!

 

[gobigracing]

OK a few more questions. I built my whole linkage using one master sketch. All is well(really well). But I do have a few questions. When I wend to assembly all the parts I ended up with crap load of cluttered sketches. Its OK if I set them to lightweight or just don't even view sketches if I don't need them but is this normal to have A LOT of sketches. Its OK now but I'm not sure if I was working with something bigger if it would slow down massively or not. Also a question I built all of the parts my the master model so should I assemble them in reference to the master model or to other parts.

Thanks. Just don't want to create any bad habits.

 

[bvanhiel]

I hide sketches that I'm not actively using (not all sketches, I hide each one individually). It keeps things from getting too cluttered.

 

[SnowCrash]

You can also change the color of the sketch. Although that may actually increase the confusion . . .

--
Hardie "Crashj" Johnson
SW 2008 SP4
Nvidia Quadro FX 1000
AMD Athalon 1.8 GHz 2 Gig RAM

 

[gobigracing]

good point. I hide objects alot never thought of hiding sketches. I really like this way of building. Alot less problems when you do major design changes.

 

[gobigracing]

Question. Is their a way to say add only part of a part into your model. Like if I make a big master sketch but break it up in many smaller ones would this work. It would be much cleaner.