Re: 3d printed ultralight airship

I have just been doing some trials for a printed core for a carbon fibre bike frame. I printed in ABS which is less dense than PLA. My idea was to try to get a core that was as light as PU foam over which I could skin carbon fibre for strength. I failed miserably even though I went to very thin walls with 5% fill. I wasn't going to use the ABS for strength, just for shape, the carbon skin would provide the strength. PU foam was still much lighter.

See here check the post for 22/10/2012 Commuter bike

What I was trying was an order less of what you are proposing, so I don't think it will be practical, unless you use powder printing as in the SULSA aircraft. Even then it might not be as light as you want.

SULSA AIRCRAFT

An alternative might be to print moulds (molds) for the parts you want, then use expandable foam to fill the cavity. PU expandable foam is the stuff you get at diy stores for gap filling around pipes. You can also get two pack mixable stuff used in boat building. I was thinking of using cling film in the mould to help release of the part. You could also add in balsa or carbon spars inside before you fill with foam. This would make a light and rigid gondola. Having said that you might be just as well using conventional balsa and tissue.