How do I delete hatch without deleting outline

I have filled a cross section outline with hatch. When I try to delete the hatch I also delete the outline. How can I delete hatch without deleting the outline please?

Is there any detailed document regarding the use and manipulation of hatch please?

Many thanks

I played around a bit and found out that if the outline is a polyline it stays selected after creation of the hatch. If you then select the hatch and delete it the outline gets deleted also.
So after having created the hatch press "Esc" on the keyboard to deselect the outline.

I don't know of detailed documentation on use and manipulation of hatch.

Thanks dellus

I have also found a work around. If all hatches are done in a separate layer to the outline then it is much easier to separate hatch from the poly-line. If I hide the poly-line layer, then delete the hatch, when I unhide the poly-line layer the poly-line outline remains.  

I was struggling with a 'solid fill' hatch but have subsequently discovered that if a typical cross hatch consisting of lines is used, then by zooming in and selecting one line of the hatch pattern and deleting that, the outline remains.

Many thanks again for your help, it inspired me to play around with it further.

Best regards

Good tips. How about putting a few notes together for working with hatches as the basis for the wiki pending incorporation into the manual?