building an rc-model of an AAV - Amphibian Assault Vehicle or LVT - Landing Vehicle Tracked or whatever they wanna call these big bits of military machinery
they're extremely expensive as ready-made RC-model kits, so I chose a cheap China-made RC-tank as a basis to start from
what I figured was that the six track wheels are the most obvious feature so I went looking for something appropriate to be butchered to pieces before rebuilding it as an AAV
eventually I paid 39 Euros for a nice, brand new 1:16 scale model of an M-26 Pershing Snow Leopard on Ebay
and ripped it all apart, basically keeping only the lower shell and the electronics
two fairly strong motors and the gears to power each side individually
I collected some plans and photos from the net and transferred the measurements to the 1:16 scale basis I was starting from
using discarded fireworks sticks and plastic sheets I started building the body
5-minute two components glue was used to stick it all together
short fixation times really speed up the construction phase
grease filled rubber sleeves are used to make the track drive wheels waterproof
then the thousand holes in the floor had to be sealed
using styrofoam has two advantages - it can easily be shaped with a hot wire or a sharp knife and the thing becomes forever unsinkable
rear loading ramp is made of wood
I salvaged a Dicki amphicar with broken gears for the top lid
the styrofoam is then covered with 1.5 mm and 0.5 mm plastic sheets, easily cut to size with scissors
couple of yoghurt cups lose their bottoms and presto - ready are the turrets
propeller shafts come sticking out of the sides - steering is via having right or left side run
the front part of the body and the battery box at the bottom can be flooded in order to have it sink low enough into the water - I expect the body being too light for correct displacement (and I was right unfortunately...)
original lights can be reused for that authentic touch
rear view with the two propellers covered by side panels
I couldn't shape the curved front fenders from plastic so I used bondo (smelly like hell inside a room)
theoretically the gun turret can be motorized, because there's still one free channel from the original RC setup - I doubt though, I'll ever finish it...
add some front lights and you're ready for paint
propeller motors are just taped in place but they don't work properly yet - guess they're too small really
left motor is controlled via the turret motor-channel turning left and right, whereas the right motor is controlled via the gun-channel only turning one way - so going backwards is going to be a pain...
complete top cover is sealed and bolted in so that battery change is through the lid
paint scheme is Corean army - if I got that correct - I just liked the airplane nose art style
gun had to go though - I'm a pacifist ;-)
a bathtub test followed and it was half successful:
- it's waterproof alright but the ass was sticking up in the air, meaning the propellers didn't touch the water, so I needed half a kilo weight in the back to make it go low enough in the water
- and for reasons I don't know, the right propeller didn't quite run smoothly, resulting in constant curves and that sucks
but no problem
I just went down to the river, got me a nice pebble and glued it in the back
so with enough ballast in the back it was time for a test run in the local gravel pit
driving on hard ground was nice
but in the mud it got stuck pretty fast
because mud and stones got between track and drive wheels and that was it
in the water it sat nice though
but it's still only going curves because of that one motor running slower than the other
result: it's just not yet what I am looking for - mud performance is not at all what I was hoping for, so what I'll be working on next is a
wheeled amphibian vehicle - stay tuned!
some piece of advice at the end - when mud testing, don't forget to wear good shoes - mine got sucked in
and yes, I was still inside!
here's a youtube flick about my AAV model