I have watched several videos of cutting foam, both manually and semi-automatic. Most of the cutting that was done was with a smooth wing, no slots for spars. I built a automatic foam cutter via plans from tailwindgliders.com. By a gentleman named Curtis. I don't understand how to do the wing with the spar cutouts in it. Looks like the hot wire will not drop down into the slots. Do you cut the slots last after the profile has been cut? I will include a picture of the wing rib profile so you will be able to see what I am talking about. Thanks`