Using Dimensional Constraints to define distance between two lines

[Anonymous]

Hopefully this is quick and obvious; I just want to use a dimensional constraint parameter set to a constant value to maintain a distance between two lines as other lines around it are stretched dynamically. When I add the constraint it defaults to d5=0, I type in d5=.125 and hit enter and the expression field in the parameters manager updates to .125 but the value remains set to zero and the constraint is still displayed as d5=0. Any insight on this is greatly appreciated, I am sure there something missing about how these constraints are meant to work. Thanks!

[vinodkl · Accepted solution]

Hi,

What is the precision set in "UNITS" ? is it set to "0"?

[Libbya]

Post the block.

Why would you need to add any constraints "in order to maintain a constant distance between two lines while other lines are stretched around them"?  Simply don't stretch those two lines in different ways.  In 90%+ of cases, using constraints in dynamic blocks is unnecessary and causes more problems than it helps.  In 98%+ of cases, adding constraints to dynamic blocks WITH dynamic parameters/actions only causes problems.  

Post the block.

[Anonymous]

Yes that was it, thank you very much. i knew it would be something simple!

[Anonymous]

IT dept might not be happy with me posting a .dwg with a block that one could potentially gleen product info off, but thank you for that advice. I think the issue is that I'm not stretching the block (I know that's what I said before, misspoke)  but rather I have a block table that drives changes to my outermost line but it behaves unexpectedly and the relationships between the other lines that I don't want to move isn't maintained, hence the reason I am adding constraints. 

Fairly new to ACAD coming from Solidworks and Creo, so I am kind of working throught this dynamic blocks stuff

[Libbya]

Your description sounds like the block would fall in that 90% category where it would be more effectively made without any constraints and with only the use of dynamic parameters/actions.  The benefits would include more consistent behavior, smaller file size, reduced load on computing resources, etc...