Had a few barrels printed on Shapeways 2x MG18's and a MG34 and 2cm KwK 30 (for my PZ II)
On the tank
On/off switch and volume control-
The internals
I've added some large washers (wrapped in insulation tape) to add a bit of weight. It's a tight fit in there so nothing can move around.
Now I just need to paint it.