Hello,

I am fighting this problem for second day now and I really dont know, what could cause that.

Attached file describes the geometry. 

FIRST IMAGE - is the desired situation: a dimension is attached to main axis  (when I click the main axis, it shows correct  relation to dimension)

SECOND IMAGE - after I go from sketch to part enviroment and back (literaly two clicks), the dimension de-attaches and it is attached to construction axis shown in red or yellow (when I click on the main axis, relation is missing)

THIRD IMAGE -  On the ,,what happened" image is shown what I assume could happen

The dimension has unattached from its original axis to a minor one, either the one shown in red or yellow (depending on which I delete before I exit the sketch)

- if I delete all minor axes (used for construction purposes) the dimension is attached to a "zero distance" point on the oudside diameter.

Things what I have tried:

-Create Axis 1 as a line with ,,construction" ticked

-Create Axis 1 as an centerline

all caused the same

Really dont know what can cause this, the dimension is used on the drawing, I need to project it directly, cause the nominal and tolerances are driven from design table, and this crippled position is unacceptable. I have discovered that the measured distance, between the main axis and the outside-diameter is ALWAYS CORRECT, even if the distance between the arrows of the dimension is for example size of 2mm (number displayed would be 75).

(Note: you can se an equation warning, this is caused by deleting all other confidental dimensions with tolerances)

Thank you all in advance for any suggestions and tips !