If you need to insert a hatch in an area that isn’t completely “closed” this may be your new favorite friend. Instead of temporarily making a line to close off the area and then inserting the hatch and then going back to erase the temporary line (which you may forget about) you can change this setting. By default, this setting is set to zero which means that a hatch area has to be completely closed. You can set this to a value up to 5,000.

There are a number of ways to change this setting.

AutoCAD Classic: via the Hatch Dialog Box:

If you have a newer version of AutoCAD that uses the RIBBON, you can get to the old Hatch Dialog box by clicking on the diagonal arrow on the “Options” panel (as seen below)

To expand the Hatch Dialog box, Click the Arrow that points to the right (as seen above).

Now you can see the Gap tolerance are and make any changes in this area (as seen below)

From the Ribbon:

Expand the Options panel on the Hatch Ribbon and change the Gap Tolerance setting (as seen below)

From the command line (as seen below)

• HPGAPTOL <enter>
• Change the value

As  you can see above, there is a gap of 0.7 units. I changed the setting to “ignore” gaps that equal 0.7 or less when I hatch an area.