Outer Limits 4x4 Board

hey guys stupid question, ( yea ive been searchin to no avail),
buildin a 45 series, and when i run out of materials i keep workin on the doors, till the other day i realised the sports doors ive cut and am about to weld... on the angle down bit on the inside skin curves in and isn't the same width as the rest, i figure ill just bend the bit of plate over to make it look flat, but wondering how did everone overcome this?? cheers for the idea

loooooosecanon

I just capped mine with some 1mm sheet.. Tacked in place, ground to follow the contour of the irregularities on the inner, then fully welded..