Replacement Cowling for Guillow's 504 Supermarine Spitfire Model Airplane

Everyone who has flown one of these models long enough has experienced a cracked cowling. This is a printable replacement part for Guillow's 504 Supermarine Spitfire balsa model airplane.

A tiny bit of infill with single walls compares favorably to the original vacuum formed part strength-wise. I used an infill modifier to increase infill for the flat section holding the thrust button. Supports are required.

While it can be slightly heavier than the original cowling, to keep the CG in place you will probably remove some of the balancing weight you'd needed before.  On my plane, the new cowling is about 2.5g heavier than the original, but after balancing the plane gained about 1g (I couldn't get the added weights quite as far forward).

Depending on how much you sanded the first fuselage former, you may want to shrink it by about 1% or so.  The thrust button will still fit.