I've spent a lot of time the past two weeks on an assembly model and detail drawings for one of our machines. I have run into several issues that I consider serious when trying to implement an Alternate Position Assemblies. Basically I have a machine with some doors I want to show in the closed position and in the open position. The combination of long save times, non-intuitive settings and rules and frustration with assembly drawings parts lists indicate a need for major improvements. About 15 years ago, I experimented with alternate family members with (assembly variation with different parts) with poor results. Here is a begnning list of what I have run into over the past two weeks:
Alternate Position Family of Assembly Issues (All parts the same just different positions)
Parts lists cannot be accessed and linked across family members in different drawing views
Cannot open multiple family members
Cannot transfer parts from FOA member to another subassembly or to top level assembly
The “apply edits to all members” is not needed. That is the only choice for an alternate Position FOA -all the parts are the same.
Long save times. The more members the longer it takes
Too many limitations and special rules
The valve example in the help file may show a basic concept of FOAs, but when you try to use it for something in a more complex, real world setting, the limitations start to pile up.
As I mentioned in my earlier attempt to use Families of Assemblies for a machine that had 6 different variations, I ran into so many roadblocks that I ended up saving all of them out as separate models and had to keep up with them manually. There should not be a case where something that should be managing a complex model should take so much effort and time that it's actually easier to use a brute force method.
I initally thought an Alternate Position assembly would be easier to manage since there is only one set of parts, but I'm not so sure now. By the way, I have 4 more machines that may need something along these lines, but I'm starting to worry that the software is not up to the task.
Another item for the list:
Going back to my example where I have a drawing view with Position 2:
1. Double click on the view and open the model with the Position 2 member
2. Realize I need to look at the assembly model for Position 1
3. The members pull down is grayed out and I can't access Position 1.
4. Try to use "file open" and open the Position 1 model. Solid Edge will display a pull down box so I can select which model to open. Pick Position 1 - nothing happens. I assume it's becuase Postion 2 is open but there's no error message or any other indication that I can't do that.
5. Now I have to close the Position 2 assembly so I can open Position 1. Closing an re-opening can take quite a bit of time - more members equals more time. Doing this back and forth can burn up a day really quickly.
I also have all of these problems. I use alternate assemblies A LOT because the various SKUs we design only have small differences between them.
My biggest complaints are : save time, moving parts between levels, and interactions with drafts/parts lists/item numbers as kjoiner described.
Additionally I wish xpress route would treat each family member differently if desired. Currently I need different wiring for each memeber of the family and it becomes a complete mess. I've found it is easier to use a seperate assembly to generate the xpress route wires and then bring them back into the FOA with no diret links to the FOA.
I also find it very frustrating that all of my drafts will prompt for updates if I only change one family member.
FOA functionalitly would be perfect if these areas could be improved. Even given these issues I still find it useful compared to the alternative of keeping all seperate assemblies up to date manually.
I came across another needed enhancement for Alternate Position Assemblies:
1.I'm working on another machine and its associated assembly drawing.
2.I realized I needed to make an alternate assembly model to show some doors in various positions.
3. I copied the assembly to a new name in case I make a mistake and I'll still have the original as a backup.
4. Open the draft file in Design Manager and try to swap the new model in for the old one - nothing happens.
It seems that a model that has altenrate position members in it cannot be swapped in for one that doesn't.
I was just able to swap it in - I had to close the assembly model first, however.
Today I just lost over 2 hours fighting with incorrect item numbers in an assembly drawing that uses alternate assemblies.
1. I created a BOM off of one family member - a machine with the main door closed.
2. On another sheet I created a view of a family member with the door opened
3. I checked "use asembly generated item numbers" in the BOM options
4. I assigned item numbers in the assembly model.
On the view with the door opened, when I balloon items, some item numbers are completely wrong. I have a rod that should be item 13 ballooning as item 7. Well, item 7 is a hinge plate. But then when I balloon the hinge plate, it's showing up as item 8.
I have a similar machine using the same methods that balloons out correctly.
Something has to be done about Families of Assemblies. As I mentioned before, I tried it 13 years ago and it was a mess. Not a lot has changed in that time. It's very frustrating to have to go through the long wait times to save FOAs , deal with arcane rules and check boxes to get something to work. I'll probably have to back up and start over and lose hours of work. I think someone at Solid Edge needs to actually try this out in the real world and find out how difficult it is to produce a set of drawings using the tools available.
Tomorrow I'll send in an IR and see if I can figure out what's going on. The help file sure isn't going to provide any guidance.
Yeah, I've sort of "swore off" APAs ever since I tried them in the early part of the century. People at my former and current work places also made/make sour faces when the subject of APAs come up. Or they just laugh. It's a shame.
It seems like most people opt to put in a second copy of the moving parts/assemblies using configurations and occurence properties to manage views, etc. rather than deal with APA issues.
As much as I would like to use a more straightforward approach, I have to create assembly drawings that show our machines with various doors in open and closed positions. It's painfully slow, with just 3 members (the master, door closed, door opened) when I hit the save button, I have to sit and wait for it to save. I went through a lot of pains as evidenced in the earlier posts in this thread to get the BOMs to behave and thought I had it worked out. This current machine is very similar to the other one so I should be able to apply the same method.
As I mentioned earlier, in this thread, there is no reason why managing BOMs among alternate position assemblies should be so difficult. All the parts are the same. Therefore, when creating views in an assembly drawing that use various members of an FOA, all the BOMs should be linked. Instead, you have to know the "secret" check boxes in the drawing and the model to allow the model to drive the item numbers in the drawing. And now the balloons and BOM seem to have a mind of their own. I'll try to post some images tomorrow.
FOAs need a lot of focus on upcoming versions. Generative design is neat, but unless you are in the casting business or 3D printing parts, it's not an every day tool. Documenting how to make parts and showing how to put them together with different configurations or positions is common in the machine world.
OK, I think I got the item number issue worked out. As mentioned in one of my ealier posts, I had to create a "dummy" parts list for the door open view, then check the box for "use assembly generated item numbers" for the new BOM. Again, why should I have to create another BOM for a view that should be tied back to the master BOM? All the parts are the same, just in different positions. At least I don't have to scrap drawing.
Here's another issue - simplified parts. I have a rotary damper that has two ears on it. We cut one off so I have a simplified model of the damper with one ear removed. In the assembly model, I select "use simplified part" and also have a view configuration set. In the drawing view, however, the damper shows both ears. Am I missing another "trick"?