Level of Detail or Design Rep?

[-Aaron-]

I have a decent size assembly, 3000 parts total.  Now, I must say, that I have toiled with, but have not dove deep enough into Level of Details to correctly utilize them.  

Now that that's out of the way, let's start by telling my work flow.  

I create a Design Rep with the parts that I would like to have in my LOD.  Set up my Design Rep, and then I Copy to Level of Detail.  All fine and dandy, I can switch back and forth between LODs no problem, everything looks great on screen.  

Now, I go and start my drawing with said LOD as my view, dimension it up, save & close.  I come in today and continue work on my drawings only to find that all my dimensions have gone away.  Please see attached PNGs.  The TODAY pic shows what I came into this morning.  the OLD VERSION is what I saved on Friday.  No weekend work, and nothing on the original assembly was changed or altered...

Has anyone seen behavior like this before?? Yes, I've searched these boards, but the 

I would like to get away from using Design Reps all the time, as they don't save on RAM usage.  

Maybe I should look more closely into the LOD usage.

[PaulMunford · Accepted solution]

I don't know why your dims disapeard, maybe it's to do with memeory?

One thing I do when a drawing made from a large assembly goes screwy is shut down all the programes I have running, Delete everything out of the %temp% file, reboot, fire up inventor, click on the master view and regen.

This is painfull - but it often does the trick.

In the mean time, I think that you should investigate LOD's and view reps a little more.

Level of details actually unload parts from memory, View reps just hide them. Using LOD's for drawing views can save you a lot of memory. There are a couple od caveats though - Don't use more that one LOD per assembly, and if you add part Ballons you may undo all your hard work.

Check out these posts:

View Representations vs. Levels of Detail 

How and When to use Autodesk Inventor LOD Rep's for Assembly drawings 

Autodesk Inventor, Creating a coordinated BOM for Large Assemblies

Let me know if that helps!

[-Aaron-]

Paul, the second link you give is what I was looking for.  Thanks much for that!  I didn't realize that it wasn't common practice NOT to reference more than 1 LOD per drawing. I have a sneaky feeling that's the case with my missing dims maybe??  The other 2 links are just as good and I will put those into practice.

Thanks for the help!!!

[PaulMunford]

Great! Glad I could help 🙂

[moto748]

Yes, I found those links really informative too.

Just to be 101% crystal clear, when it says, don't use more than one LOD in a drawing, does it mean "not more than one new one, plus the Master" (which IIRC you can't get rid of anyway), or does it mean "Only use one LOD. If you create a new one fro use in the drawing, don't use the Master in the drawing as well"?

Thanks.

[RyanBotha]

I think its 1 LOD total, so whether it is MASTER or a custom LOD, there should only be one. I wish I knew this a year ago. We also had a drawing fall to pieces due to 'weekend gnomes' altering the drawings. Was all due to multiple LODs.

[PaulMunford]

That's right, a call to the Master is exactly the same as a call to an LOD. Every call to an LOD is like you are calling another Master Assembly. Inventor doesn't recongnize that they are all different versions of the same files.

Having said that, I had this pointed out to me in a support call from Autodesk - so I know that they know that it's a problem. I hope that they are working on it!

[moto748]

Thanks, Paul and Ryan.