The company I work for sent me and some others from our plant to Friedrichshafen Germany to the Zeppelin plant to inspect equipment and observe the operation of a new line we are getting.
We went to the Zeppelin Museum and got to go in the passenger compartment of a re-creation of the Hindenburg. It was interesting to see the construction of the Hindenburg was similar to what I have seen in homebuilt aluminum aircraft. They had an assorment of rivet squeezers on display. It looked like the Zeppelin structure was squeezer friendly and I doubt they needed bucking bars and hammers very much. They showed the roll forms and the various stages of formed aluminum channels. They also showed the stampings from blank to finished for the parts between channels. The structure was made from sections similar to TV antenna towers with 3 channels and the stamped pieces rivited between them.
They wouldn't let us take pictures in the Museum but much of what they had has pictures available on the internet. They had Zeppelin engines up to 16 cylinder 500hp and a Prop I would estimate to be 20ft dia or maybe more.
The plant in Friedrichshafen makes silos and material handling systems, etc. We saw some big slip roll forming equipment and such for making the large silos. Their silos were TIG welded together.
I think they had something to do with making the Goodyear blimps and they have a few Zeppelin blimps in Germany. They had some parts of a Zeppelin blimp they were in the process of constructing. The Zeppelins they build now are 12 passenger and the length of the Hindenburgs Aileron (that's what they said, I think they might have been speaking of what I would call the tail fins).
There is nothing left of the original plants because the area was heavily bombed in the last days of WWII. The old Zeppelin airships were recycled to make warplanes and the V-2 rocket engines were made "there", I'm not sure if "there" meant the Zeppelin plant or another plant in the city.
Gasoline in Germany was 1.40 Euros per litre, I haven't calculated it out but with the exchange rates and all it would come out to about $7-$8 per gallon.
RogerN