Stretching constrained blocks

[Joe695170]

I am hoping to create a block that can be stretched in the X axis using grips, preserving diagonal lines meeting at a center point in the block. I have constrained the block accordingly, and it seems to work as long as the width of the unit is typed in. Surprisingly the constraints fail when the grips are used manually. Is there any way the constraints or parameters can be modified to allow for manual stretching?

The block in question is attached.

[LSElite]

you can do this without using geometric constraints.
I have attached with a quick edit I made.
to keep the lines in the center just use a stretch around the center lines with a 0.5 multiplier.
do this in both directions and it will work.
I added a 0.5 move to the red text to keep it centered but if you want the block to run quicker this can be put into the stretch also.

[Joe695170]

Great thank you.

I wouldn't have thought to constrain the .5 stretch window to the center point. I had tried similar scaled stretches.

Also my block is embarrassingly complex I know, I hadn't discovered the "modify selection set" function until recently :roll:.