Hello Martin!
It's made of plastictubes for electric wire and styrene sheet and some brass rod and tube. The white tube with motor, coupling, shaft and propeller already connected is inserted into the blue housing and secured to the flange. I hope some vaseline in the housing will keep the water out. Perhaps some more pictures could help out. You ask about the glue, yes thats what I'm a little worried about. I tried plastic glue and it worked on some parts but not all, most of it is glued with meltglue with a gluegun( am I right here, not sure what it's called ). It seems to work and give a good and watertight joint and I used it on a smaller thruster I made two years ago. I`ll see if I dare to put it in my precious model when time comes. You must excuse me for not getting the words right sometimes, its always difficult but now its getting late as well.
Thanks for your interest!