The top and rear cover on this type of BMW engine were too
high for this frame, plus they were full of all sorts of holes
and BMW aluminum is difficult to weld, so I decided to make
new covers. I started making a positive mold of the shape I
wanted, using 18mm MDF. The first parts were slotted so that
they slide into eachother, forming a strong base to clamp the
rest of the pieces into.