Thanks for your advice 'Willem' I will certainly try your suggestion.
I am finding V0.18 difficult to use, probably an age thing..........(75)
Regards.
Many thanks 'openBrain' for taking the time to read, react and rectify my post. I had intended to attach the PDF of the part drawing of the Steam dome which I have now included in the event anyone is interested. In truth I had many problems trying to download Graphviz but have now managed to install...
I have found several instances where a constraint cannot be placed or changed unless another local constraint is removed, not sure if they have to be in a specified order to be compatible with each other.
Don't know if this helps, I had a little play with your sketch and found the same issues you have, however if you remove the parallel constraint, change the angle then reapply the parallel constraint it works.
H,i I hope you enjoy this project also, I did this underslung engine model in V0.16 a little over a year ago, had a problem with the drive chain though.
Nice work.
Regret, not able to answer kisoire questions, The space between Radius dimension and line is where techdraws puts it, as I indicated I am new to TechDraw, however it seems that Drawing Dimensions in earlier FC versions was more flexible, I still welcome any further guidance here.
FreeCAD