The one I've found that
looks best so far in terms of power, speed, and price is the Hitec-hs805. It
weighs over 5 oz, moves quickly, and has a lot of torque. Specifics are
here:
If you (or anyone else) knows of something
that will work better, please, let me know. My plan here is to make the
servo mounts/brake assemblies work for two of these servos per side, but
initially only use one per side. If that turns out not to be enough I can
buy and install two more later.
My friend from work, Paul, helped me out some last
night by drilling holes in the other aluminum channel that goes inside the
right-hand track assembly. We really got a lot done:
I figured out a different configuration for the
batteries that leaves more room in the middle of the tank. Notice one battery
inside each track. I stuck a 3/4" rod through the bearing holes for the
differential to show where that will go. I made the angled front plate by
brazing a piece of steel angle to the edge of a piece of 1/16" 4130 steel and
bending bending it by hand up around the front of the baseplate. This piece
serves to protect the front of the lexan baseplate from impacts - I heat treated
this steel piece to make it nice and strong.
I've also been sharing this progress report on the
Robot Fighting League (RFL) forum. Someone there pointed out how my tank is
disproportionately wide. I mocked up the tank with cardboard and when I went to
build it from my scrap materials, I realized my sheet of fiberglass wasn't quite
big enough. I had to shorten the length of the tank to just a little over three
feet to get the side panels out of the partial sheet I had on hand. As pictured,
the tank is 18" wide, so the ratio of length to width is not quite right. I
wanted to ask how critical it is that these proportions be just right. It would
probably be possible to rearrange things and narrow it up a bit. Either way, I
intend to do all the little details like rivets, holes, right color paint
etc. Being wide may have the advantage of staying upright better, it will be
interesting to see how this tank behaves with no suspension. I built a
similar-size non-tracked vehicle that was quite amusing to see cartwheeling down
the street when it would hit a pothole :)
Just one more question: How much driving do the model
tanks normally do on pavement. My intention has been to make steel tracks, but
those probably won't do well on hard surfaces. One solution could be to add some
hard rubber "buttons" screwed into the tracks for grip.
Gene
From: tanks-admin-at-rctankcombat.com
[mailto:tanks-admin-at-rctankcombat.com] On Behalf Of
OdysseySlipways-at-aol.com
Sent: Tuesday, October 17, 2006 2:00 PM
To: tanks-at-rctankcombat.com
Subject: Re: Gene is building a tank! [TANKS]
Sent: Tuesday, October 17, 2006 2:00 PM
To: tanks-at-rctankcombat.com
Subject: Re: Gene is building a tank! [TANKS]
big servo's or sail winches?
Chris,
Odyssey Slipways
Odyssey Slipways