I just started building the 1/35 dragon opel blitz gun truck.
I’ve always had this question since I have built other Opel blitz trucks and that is is the undercarriage pieces, springs, mufflers, etc. painted gray or would they have been a steel color and overtime just weathered with the elements?
This is the underside of an unrestored 251 halftrack. Generally speaking, anything that could be reached with a spray gun would be. Brake lines and wiring were added after the frame was painted. Late war, this may have been left in red oxide primer, early war, this would have been Dunkelgrau.
Leaving it unpainted would be rather unlogical, as the components would have been exposed to all kinds of dirt an moist, making it prone to oxidation (rust).
It would be painted body colour, either Dunkelgrau, or after February 1943, Dunkelgelb. Having said that, the exhausts might have been left steel, as they would quickly rust due to the heat and the paint would fall off anyway. Like most people here I suspect, I paint the exhausts in rust.
Thank you all for your input.
The Blitz was first assembled as a rolling, running chassis. I doulbt they would paint the exhaust system but it might still get hit with overdpray. Or perhaps they instslled the exhaust as a final step. In any cast the frame and other components would have been fully painted before any body panels were installed.
As to modeling the exhaust i always hit the entire exhaust system with rust as the bare metal would turn in just a matter of months or weeks.
I have wartime photos of fully assembled and painted Blitz chassis. I am on the road now but will post them here when i get home.
p.s. here is the link to my Blitz photo reference thread in the KitMaker Archives:

