Lock dimensions in objects when changing family

[ArthurADas]

Hi

I created, from 1 family, a bunch of others families with the parameters values different (I have my reasons).

What im trying to do is insert one family in a Sheet, put some dimensions on it, and from there change the family, and those dimensions follow the references from the changed family. Everything worked just fine as shown on the print attached, but the dimensions didnt follow the offset (pointed in the print too). Is there a way to lock that offset? 

My objective may be a little confuse with this text, but using the print as reference you can easily undestand, i hope.

Thanks 

Arthur

[barthbradley]

Sounds like you are using Type Parameters when you should be using Instance Parameters.   

Actually, I don't know if that's right. I don't fully understand what you are describing or showing. Post the file to look at. 

[ArthurADas]

I will try to be clearer. In a project a have 2 families, both modeled the same way, the only difference is the value of two parameters (“a” and “b”). What i need is when i change the family from family 1 to family 2, the dimensions (the number that pops up when using the “dimension” tool) remain positioned close to the object. Using the image as an exemple, when i change from family “1” to family “2”, the dimensions 3000 and 1500 becomes 2300 and 880, everything working just fine. But when this change happens, the offset from the value 2300 to the object increases a lot, the same way happens to the 880 dimension to the object. What i need is to make this offset to stay the same as it was before changing to the familiy “2”.

Ps: I can only post the file tomorrow if its not a problem

[barthbradley]

Okay, so now it sounds like you want it to "grow" in one particular direction. Pin the Ref. Line that remains stationary. If it "grows" outward from the center, equally on both sides, use an "EQ" dimension.  I'm I getting closer? 

[ToanDN]

Edit both families, place a dimension defining the offset and lock it.

[ArthurADas]

@barthbradley @ToanDN 

Toan, thank you for your answer

Bradley, thank you for your patience.

I dont know if we are aligned with the same idea, so i made this step by step showing exactly what i'm doing.

The project with the families are located on this google drive link as "Project.rvt" and "Family1" and "Family2" and i'm attaching the step by step image. 

I hope it can clarify all of this. My vocabulary is not so extensive so i might be missing some essential words that could make things simple.

https://drive.google.com/open?id=1gXqrAQEz3DI-0el0tkNw5DJ5aAIlFs0B

[barthbradley]

What's wrong with the above two screenshots?  

[ArthurADas]

In family "1" I placed the dimensions at distance X, as shown in file "1". After making the change from Family 1 to Family 2, this dimension, which had the distance X from the object to which it was positioned, became Y (The distance increased). When the family is changed, I need this distance X to be maintained and not grow as it is happening.