SSP and moving parts

[josh]

I'm about to start a small project and thought it might be a good chance to try out the SSP method. I know the rough shape but final dimensions will be coming later.

I've read @mattpeneguy's PDF guide and I generally understand what we're shooting for, but how do you SSP pros deal with moving parts in assemblies since everything is put in with in-place mates? I have 2 parts that need to slide in and out, and then a lid assembly that I'd like to be able to pull off the top. Do you achieve this by modifying the SSP sketch rather than dragging parts around?

[Tom G]

To me, it depends what you are driving with your SSP. Not everything needs driven. Some parts can be independent and live normally within the assembly. Basically, not everything has to follow any rule. If you have driven and independent bits, it may be useful to distinguish those clearly to avoid SSP assumptions later. Comments help record user choices for future you.

I don't generate parts with my SSP, but others do. I generate mate references in my SSP, for library parts to populate upon. My method would work for what I understand of your purpose, by allowing a part to reside along an axis to allow axial movement. Is your movement simple as a trombone slide, or complex as a front end loader with compound hinge, pneumatic pistons, and lever arms?

[matt]

Whenever I have some sort of "system" (like ssp) to control parts, I handle motion in one of two ways:

- make a separate assembly for motion
- insert additional instances of moving parts, and hide the instances with the driving relations

Of these, the first is less risky because you're not mixing driving and driven parts in the same assembly.

If you do SSP in an assembly and are driving parts with in-context relations in the assembly, using parts driven by in-context in other parts can put you in danger of triggering the multiple contexts warnings. There is a switch that allows you to create in-context relations to a single part from multiple assemblies, but you want to be careful about using that.

[mike miller]

I'm about to start a small project and thought it might be a good chance to try out the SSP method. I know the rough shape but final dimensions will be coming later.

I've read @mattpeneguy's PDF guide and I generally understand what we're shooting for, but how do you SSP pros deal with moving parts in assemblies since everything is put in with in-place mates? I have 2 parts that need to slide in and out, and then a lid assembly that I'd like to be able to pull off the top. Do you achieve this by modifying the SSP sketch rather than dragging parts around?

One good way is to use separate assemblies.

As in:
-one assembly for the final product which drives the lower level parts through the SSP part.
-one assembly to check motion and clearances using mates and/or fixing to origin. (No references are created here.)
-one assembly for rendering with all appearances turned on.

This allows the best of both worlds.

[edit: didn't see matt's post, which says essentially the same thing.]

[Frederick_Law]

My SSP (Master Sketch) is static. Control shape and location of all parts.
Assembly and sub assembly is required to show movement which works with config to show overlay.

And there is no "right" way.
Play with it and see what works for you.

[Roasted By John]

@josh

To add anything... The moveable component, is it a purchased item or are you designing/modeling it from scratch?

Echoing what was mentioned before, the SSP and the Sub-Assemblies with the SSP controlling all the components are always "Static", if you want to show movement open a "New Assembly" and put in the sub-assemblies that you need to show moving components, what's nice about this workflow, now you can go to the feature tree and edit any SSP that is listed, make the changes to see how it affects your assembly.

[jcapriotti]

Is SSP and In-Context the same thing?

I view SSP as a master part model with sketches, planes, etc. inserted into new part files with geometry constrained to the inserted master part geometry. Then you assemble the parts with mates or constrain it to the same master part in the assembly.

In-context I view as.....don't do it.

[Roasted By John]

Is SSP and In-Context the same thing?

I view SSP as a master part model with sketches, planes, etc. inserted into new part files with geometry constrained to the inserted master part geometry. Then you assemble the parts with mates or constrain it to the same master part in the assembly.

In-context I view as.....don't do it.

In-Context and SSP (Same Thing), I would say yes, but there is one big difference,

The In-Context Design that I think you are referring to is building one part off the face of the prior part in the feature tree, that is what I call "Building A House Of Cards", pull out the bottom card and the entire building collapses.

The SSP, is also "In-Context Design", however you build your part off the SSP and nothing else, the parts "Share" information, but are not stacked, which reduces a lot of issues in the Design Process.

Most people have a hard time wrapping their head around the SSP - try it out first, if you have issues, post them here

[jcapriotti]

@Roasted By John

No I get what you're say, those are both in-context meaning the parts in the assembly are driven by geometry off other parts (whether a master part or not) through the assembly.

What I mean is building a master part model then insert it into a new part file that needs to be driven by it. Then build the features of that part off the inserted geometry. No in-context relations are created as the work isn't done in the assembly. When done, you insert the parts into an assembly and mate them. So you get the parts being driven by a master design but also assembly motion.

[mattpeneguy]

I'm about to start a small project and thought it might be a good chance to try out the SSP method. I know the rough shape but final dimensions will be coming later.

I've read @mattpeneguy's PDF guide and I generally understand what we're shooting for, but how do you SSP pros deal with moving parts in assemblies since everything is put in with in-place mates? I have 2 parts that need to slide in and out, and then a lid assembly that I'd like to be able to pull off the top. Do you achieve this by modifying the SSP sketch rather than dragging parts around?

I think you are getting some good advice here. Unfortunately motion is the Achilles' heel of the SSP method. I don't think there's one single method to handle it that's going to work in all instances. We've had some limited success by reinserting the part/s we want to move, and suppressing the driven version. Managing that with configurations can quickly become a big mess, though...But, recreating a large assembly from scratch could be a bigger headache. Whatever you do, make a backup, be careful, and test, test, test...The best method is always the one that works well after a lot of denial and error testing.

[matt]

Most people have a hard time wrapping their head around the SSP - try it out first, if you have issues, post them here

John, don't take this the wrong way, it seems like you consider ssp to be your baby. Pro/E users always used planes as reference, without a special name for it. It was just the way they were taught to work. This method has been around a long time. Pro/E taught people best practices. Solidworks came along and emphasized ease of use. You can still use the Pro/E methods in Solidworks, but the Solidworks training pushes people down the ease of use path pretty hard.

There have also been other methods people have put names on, and they all are essentially making references to stable things high up the tree. The further down the tree your relation connects, the more it is reliant on parent/child rebuilds and stability. There are a lot of ways to handle things, and they've all been around for decades.

[Frederick_Law]

Is SSP and In-Context the same thing?

I view SSP as a master part model with sketches, planes, etc. inserted into new part files with geometry constrained to the inserted master part geometry. Then you assemble the parts with mates or constrain it to the same master part in the assembly.

In-context I view as.....don't do it.

This is "Master Sketch" part of "SSP".
You can say its in context. A master in context of another part.

The kind of in context you want to avoid is inside assembly. Most user do that without a plan. So reference are all over the place. Very difficult to trace.

SSP is trying to fix that by in-context to only one file, part of assembly.

I do use a Master Assembly to drive sketch in the Master Sketch.
All modeled parts only reference Master Sketch.

[Roasted By John]

John, don't take this the wrong way, it seems like you consider ssp to be your baby.

Absolutely, try to find any reference to the SSP before I brought it to the SW Forum about 5 or 6 years ago, you won't find any reference to the Acronym prior to that..

Here is the bottom line, there are many similar methods that were used for years or even better methods then what we use today.... That was somewhat that sold me SolidWorks years ago (1997), the selling point was the guy shooting his big bore animated gun through all the parts, wham o, just like that.

For some reason most people are not trained properly when it comes down to it.. It took me a longtime (must be a slow learner), finding a process that works consistently when working with "New Designs", stuff that was never made before, etc.... It took a lot of testing and dry runs in perfecting what we have now, not with ProE and other software, I'm talking about SolidWorks. The VAR's haven't been pushing it, but I think Javelin is taking it to the next level, is that right @Alin ??

Here is the real deal, The SSP is everyone's baby, they can change it to their own comfort level, based on what they are designing, so don't be jealous that the SSP is my baby

[Frederick_Law]

Master Sketch assembly moving part with purchase reference.
SW2021

Normally, parts will be fixed to origin. Or mate to 3 planes.
For one to move, it need to mate properly.

[mattpeneguy]

Most people have a hard time wrapping their head around the SSP - try it out first, if you have issues, post them here

John, don't take this the wrong way, it seems like you consider ssp to be your baby. Pro/E users always used planes as reference, without a special name for it. It was just the way they were taught to work. This method has been around a long time. Pro/E taught people best practices. Solidworks came along and emphasized ease of use. You can still use the Pro/E methods in Solidworks, but the Solidworks training pushes people down the ease of use path pretty hard.

There have also been other methods people have put names on, and they all are essentially making references to stable things high up the tree. The further down the tree your relation connects, the more it is reliant on parent/child rebuilds and stability. There are a lot of ways to handle things, and they've all been around for decades.

@matt,
I believe you are right...It's like there was a mini dark age of CAD brought about, in part, by SW. When I jumped into SW from 2D CAD, all I had was the VAR training, your books, the internet, my VAR, and the old forum. I learned the hard way that you have to be very careful and deliberate about the way that you model anything with even a small amount of complexity.
There is very scant information on robust in-context modeling...Anywhere! (There are claims, but when you actually try to break the models, most break pretty darn easy) I know they do it in the automotive and aerospace industries. But apparently all the CAD guides for the techniques they use are proprietary (try finding one...I couldn't). So, all the seasoned people know how to do it, what the do's and don'ts are, but people new to SW or who haven't gone down that rabbit hole have very little guidance.
I'm by no means an expert, but at this point, I'd guess I know a little more about it than the average user. And it was very difficult for me to get to this point. How's a new user supposed to get to where I'm at?

[DanPihlaja]

I'm about to start a small project and thought it might be a good chance to try out the SSP method. I know the rough shape but final dimensions will be coming later.

I've read @mattpeneguy's PDF guide and I generally understand what we're shooting for, but how do you SSP pros deal with moving parts in assemblies since everything is put in with in-place mates? I have 2 parts that need to slide in and out, and then a lid assembly that I'd like to be able to pull off the top. Do you achieve this by modifying the SSP sketch rather than dragging parts around?

This is exactly the problem that I ran into. Which is why I went to a hybrid SSP/Master Model approach.

The SSP only controls the basic location of the Master Model zones and the pre- and post movement locations (if needed). After that, the Master Model(s) control all the parts/locations/etc....

Then, I start creating my Master Models (which will consist of multi body parts). My de-burr assembly has 6 Master Models inside of it. Each model controls each zone. I split the zones up by what is connected and what is moving. That way, if something needs to move, its the entire zone that is moving.

So, for example, if a cylinder is moving an entire assembly back and forth, then everything that is connected to the cylinder is a zone. But the base plate that cylinder sits on (which isn't moving) is a different zone.

Here is my assembly with the Master Models in it:

What you are seeing at the top of the tree is the Master file, which has my customer part and my SSP in it.
Then, each of the Master Models has, as the Master file inserted into it.

Then everything is built into the that master file. I made a Master Model assembly like this only to be able to switch between my different Master Models quickly. Nothing is References in context with this assembly.

Please note: For duplicate parts, I only put 1 body of that part into the Master Model and use a derived sketch to represent the other positions. Then, at the assembly level, I position instances of that part as needed.

Once the design is complete, I create a new part for each of the bodies represented here. Then insert the appropriate Master Model into the part (using Insert...Part..) (I do it this way, because, as far as I know, this is the only way to pass through Hole Wizard data)

When you open one of the final parts, you see this as a Feature Tree:

As you can see, I have inserted the entire Master Model into the part, then used the Delete Body "keep function" on that body (this is because, if I ever add any more bodies to that Master Model, this part file will still only show that 1 body).

Then create my custom properties for that part and add anything specific to that part (in this case, the engraving that is tied to the Custom Properties for that part).

Here is the final assembly: