Grid lines not matching up on multiple XREFS

I have several XREFs containing different elements of a building. Each XREF contains an identical set of grid lines that I've drawn so that the different designers ensure their designs will fit together. I'm having trouble though laying all of these grids on top of each other when I put all of the XREFS containing the different elements together.

I'm using the align command but it's just not laying them accurately on top of each other.

I've tried redrawing a set of grid lines and copying, pasting into the different XREFs as I thought perhaps the grid lines were not drawn accurately but I'm still having issues.

The building is at world coordinates and approxiamtely 550km away from 0,0. I'm working in mm. The grid lines when laid over each other are only 0.04mm out but still I want this to be drawn perfectly and I see no reason why this can't be done.

Any ideas?

hi..

have you check the "base" of your xref?

it should be the same throught all your xref..

...

peace out

Yeah all at 0,0 and none of my grid lines have a Z co-ordinate.

mmmmm...try to detach them..purge..and re-attach.

...

peace out