steve dickey wrote:
Very interesting set. Although I couldn't tell in what picture if any of them, what did they use for sealant?
Then again it may be some kinda oil as it appears to be on the wood, the support stand, the floor... Although the two dudes on the right seem clean?
Dunno much about this, but I recall the paper tanks..which were bonded with resorcinol...were coated with fuel resistant lacquer or somesuch(butyrate or nitrate dope?) The paper tanks were truly one time use and filled just prior to takeoff.
I'd guess these wooden ones are using one of the phenolic processes like Duramold which required higher heat use or a bit lower tech process like Aeromold(a colder method) or a combo of both to reduce production times. I was looking for brushes and glue pots in the photos, but beyond the wetspot under one of the assembly benches(as you noted as well, Steve), I'm missing evidence of those. As for fuel resistant internals? Depends on how much use they were getting out of these tanks. Single use is pretty easy as in the paper tanks. Multi-use...abit harder. Maybe phenolic resin/hardener combination was effective or...what about the stuff the sealed wet fuel tanks with? A slurry of that rolled around in there would do it.
Still, the process is cheaper to produce than what it cost to mine raw materials and smelt aluminum or steel. ...And when you jettison the tanks you don't give the Axis materials you've been working really hard to deny them.