parametric part: more connections = more combinations?

[tompilzys]

Hello, I start from example: I want to build the tank (parametric part) with a few connections on it - for example 3. Each of the connection can have different size. When i finally get to the point where i specify the sizes, it means i actually have to give all possible combinations of the sizes that user can create. Am I right? But then for these 3 connections it makes really big amount of combinations for example for DN from 15 up to 300... Combination1 D1=15 D2=15 D3=15 Combination2 D1=20 D2=15 D3=15 Combination xx D1=50 D2=150 D3=65 and so on..... What if there are more connections? Is there a way to make it more automatically or faster?

[Keith.Brown]

The way that you are describing is using a table based parameter.  When using table based parameters you must specify each size combination.  If instead you set your nominal diameters to be a list based parameter then you can create a list of sizes for each connection and it will automatically create all of the size combinations for you.  Most duct fittings are created this way so you can open up a duct fitting inside of content builder and examine how it is created.  At a high level the steps are:

1. Create your part parametrically

2. Go into the Configuration Section of the size parameters and change the Data Storage of the Nominal Diameters to List

3. Go into the Values section of the size parameters and select the parameter to be changed

4. Once the parameter is selected press the Edit button in the upper left of the dialog.

A new dialog will appear that will allow you to edit the items in your list.  It is here that you may add your connection sizes for each connection.

Please note that you will not see the size combinations until you save and exit out of the content builder and start the mvpartadd command.  It is at this point that Autocad MEP will create the size combinations.

Again, i would study a duct fitting in content builder to understand the process.

Hope this helps.

[tompilzys]

Thanks for answer. I agree that with duct parts its the best to use list parameter. You chose size 500x500 and in the drawing it is 500x500. But with pipes its different. When i chose DN100 in fact in the drawing diameter it must be 114,3mm. There is a difference between the size that you see in catalog and what you have in reality. So that's why you need table to connect DN100 with real diameter 114,3. For example please check pipe reduction in content builder. You will see that connections are made as table and there you can see all possible combinations (133 for butt-welded-concentric-reduction). And that's my question if there is a way to avoid it. For more advanced parts it may be a problem to give all the combinations.

[Keith.Brown]

Your right, in your particular case then you will have to create each size combination.   There is no other way around it using the out of the box tools.

[Keith.Brown]

I thought i would add one last thing.  It is possible to create a Conditional Test in Content Builder and drive geometry off of that.  For instance i created a parametric mvpart that represents an air diffuser.  Typically on air diffusers they look different depending on if it is supply, exhaust, or return.  So i created on the symbol plane a reasonable representation of what i thought the diffuser should look like using linework.  See the included picture below.

I am able to controlthe symbol linework by controlling the diagonal lines.  If i do not want to see a diagonal line i multiply it by zero.  So i then created a list parameter called service and supplied three numbers to it called 0, 1, 2.  These numbers represent supply, return, and exhaust.  I then created 2 conditional tests called upper left diagonal and lower right diagonal.  I only used those two diagonals because they are the only two that turn on and off for the three different representations.  Then for the lower right diagonal test i used this calculation "Service = 0".  This would be true when the service number was equal to 0 or supply.  In other words i wanted this diagonal to have a length when the service was equal to Supply.  For the uppler left diagonal i used the calculation "Service <> 1".  In otherwords i wanted this to be true when service was a 0 or a 1or more appriately Supply and Exhaust. 

For conditional tests a true is represented by the integer 1 and a false is represented by a integer 0.  I then took my formulas to calculate the length of the diagonals and just multiplied it by the conditional test.  This would effectively turn the geometry off. 

Because the Service Parameter is a list, i can input the parameters for the geometry of the diffuser and it will automatically create 3 versions for me.  1 supply version, 1 return version, and 1 exhaust version.  i have attached this part to this post if you would like to examine this.  Please be aware that you must display the symbol geometry in a plan view in order for this to work.  Also it will only look different in a plan view.  The 3D view will look the same for all part types.  Additionally there is only one size because i added this part tot he parametric part wizard templates so it would be easy to create new sizes and manufacturers when i needed to.

**EDIT**  The forum will not let me add an attachement for some reason.  I have added the file to my dropbox and will leave it up there for as long as i can if anyone is interested in download the part and seeing how it was made.  Download Here

[tompilzys]

Thanks for this description. I will now try to investigate your idea and check how it works with my issue. I let you know about the results 🙂