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If it ain't one thing, it is another (Simp Reps in Dwgs)


New member
Please tell me I am wrong. In doing a benchmark of time and memory required to pull up a drawing with a simplified rep vs. the full assembly. I find all components of the assembly must be regenerated even though the views are created from the simplified rep. Does anyone know how to reduce overhead (memory and time) in producing a drawing from an assembly?


New member
When retrieving a drawing, all associated models must be retrieved as well. Some ways to improve efficiency:

1. There are about 15 options you can use that improve efficiency by reducing graphics and display quality.

2. Use the Drawing Rep tool to control which models are retrieved, views regenerated, and sheets displayed.

3. Convert views that don't change into snapshots, then delete the models from the drawing.

4. Use the Save Display option, then Retrieve a Drawing as View Only. (Very convenient when all you're doing is looking at or printing a drawing.)

Dave Martin

Torgon Industries


New member
Thanks Dave, you always come up with good answers.

The problem we have is we cannot pull up master assemblies on all of our workstations. I thought if we made simplified reps and used those simplified reps in our drawings, the overhead would be reduced. WRONG! This is a software issue and is something PTC has known about for years. I read where someone states they saw an assembly with 350,000 components. I would love to know how they actually worked with it :)


New member
substituting shrinkwraped subassemblies in reps would be the only way to see all of that data on the screen at one time. unless of course you have a mainframe super computer processing your assemblies.

you should not be calling into session, components that are excluded in the rep being used in a drawing. (if you only have one rep in the assembly and there are components excluded)

if ptc is telling you there is a bug then you are on an extremely old build of pro.

if you are using multiple reps of the same assembly in your drawing and they are all displayed then yes its possible to be calling the entire assembly into session. however, this is not a bug in the software. it is by design that the designer/engineer setup the drawing to call up all reps.

drawing mode provides functionality that allows you open the drawing into a saved view display that will only show the views you want. if you have more than one rep in your drawings i suggest that you create your view display to only show the views related to a single rep at a time. that way you're only calling up a single rep and not potentailly the entire assembly from the combination of various reps.

clear as mud?


New member
I did a benchmark by creating a drawing of the assembly and a drawing of a simplified rep. It does not matter, all components regenerate when either drawing is brought into session. I would not think it would work that way, but it does. Maybe it has to do with components of the assembly being instances? I don't know, but either way, whole assembly or simp rep in a drawing call up the same number of components.

Well, this is disconcerting. Jtbland, you are correct. I think I have figured out what the problem is. We use an Autostart Drawing. When the Autostart Drawing is used, it asks for a part/asm for your views. You have to choose the assembly, it does not give you the opportunity to choose Simplfied Rep and starts off by adding the whole assembly. The procedure I was using was to Views>Dwg Models>Set/Add Rep with no views showing on the drawing and add the simplified rep. After doing so, you cannot remove the assembly from the drawing. If you start a drawing in this way, by adding the assembly first, you cannot get rid of the assembly. Your drawing will show it is of a simplified rep, yet have to regenerate all components of the assembly.

I proved the above point by starting a blank drawing with no part/asm. Then I added a view and chose a simplified rep (a choice I was not given during Autostart Drawing). Only the components of the simplified rep were in session.

Attached is the proof only components of a simplified rep, created properly, regenerate in current session.