when I try to extrude the channels it says requires planar chain set.

I've done that but I'm having trouble thickening the channels. If I include them with the other surface it doesn't allow me to thicken and if I try to thicken them on their own they dont thicken in the desired direction.

So I have been trying for weeks to create a design I sketched out and have been struggling to convert any wireframe into a usable solid or surface. I'm honestly embarassed since I know my design technique is sloppy and I know I'm making a bunch of mistakes but if anyone can point me in the right direction I would greatly appreciate it. It's a relatively complex shape that I'm having difficulty creating in mc. The part is just a 1/4 inch thick skateboard with channels in it I've been wanting to make for years (like a pennyboard). If anyone wants to look over this project and critique my slopping drafting you would be a lifesaver. Thankyou. longboard_channelscut_10_15_18.emcam