Expert: Bob - 4/14/2008

Question
bob,
i am an interior design student, using autocad 2007 student version.  when i try to hatch, i get a pop up that that boundary already exists.  also when trying to hatch something else, it will hilite more areas than i want to. any suggestions? thanks

Answer
Hi--
Hatch is an entity deserving of a sexist name ending in the same three letters. It is hard to figure out, and sometimes erratic. Hatch is a fairly complicated calculation for the program and your computer to handle -- it can drain resources and slow you down a lot. If you dont have a very high end computer, I suggest hatching on layers you can freeze at times you are doing other work and dont need to display the hatch.

I am not sure what you are doing to get the first warning, and there are dozens of comments about what can happen when hatching.

-- I NEVER see that warning, so I think you must be hatching a different way than I do.
-- I hatch almost exclusively by dragging in a hatch from the tool palette (I have prepared the palette with my common hatches)-- then editing if necessary. (fewer clicks -- no dialog box unless I want to edit, or I can change the hatch in the Properties Palette.)
-- Some boundaries will take certain hatches easily, but not others, so I may just put in one that will take, and double click it to get the Hatch Edit and change it.
-- My rule: after 2 tries, I draw a polyline around the area (usually on  a non-plotting layer) and then hatch within that. On VERY complicated situations, I may move the pl off to the side of the drawing XX feet, hatch, and move the hatch -XX feet back.

When more areas are hatched than you wanted
1 -- the area is not closed
2 -- AutoCAD is "confused" by the complexity and misses boundaries, spilling hatch into other areas.

If it wont hatch at all:
1-- try my polyline thing
2-- be sure your objects drawn are reasonably near 0,0,0 and not hundreds of feet away

And review how you are hatching -- I would have to see the steps you are going through to find why you get that warning.

It takes a lot of practice, and is still difficult -- so persevere and try various ways when you have a problem.  You are lucky to be on a newer version, where hatch can be trimmed and boundaries re-created. We suffered without those for a long time.

Practice, then write back if you want.

BOB