| From: | "Chrysanthos Kanellopoulos" <xchrysk-at-otenet.gr> |
| Subject: | Polanik. New. [TANKS] |
| Date: | Thu, 9 Nov 2006 16:54:32 +0200 |
| Reply-To: | tanks-at-rctankcombat.com |
|
Polanik,
try to use drills of 18 V of 24 V at 550 rpm or undervolted / adjusted with
a trimmer to go down to 350-400 rpm
and angle drives as differentials :
I've found good quality angle drives for euro 20. The diameter of their
axles is about 8-9 mms Would that be thin for a vehicle's weight of 40-50
kgrs? I don't know.
CHrys
I made my plans fromscaling up a 1/72 scale model.
It is 1/7 th scale. It is about 41 inches long not including barrel. I didn't go
1/6 th becouse it would have been huge. The motors I am going to try are 18v
drill motors to a kiddy car gearbox.
----- Original Message -----
Sent: Tuesday, November 07, 2006 7:37 AM
Subject: availability what materials Martin,
I know what you mean about non-availability of
materials. It is not easy to get these motors for wheelchairs or kiddiecars as
separate spare parts. When I was looking for similar motors, at some point
I thought it would be more convenient to buy a whole kiddie car, use it as it
is, fix an RC receiver to control its steering system and replace the
upper hull with something that looked like a British Daimler or Ferret made out
of polyesterine and painted flat desert yellow. It would have been easier than
finding the motor only!. That's still an idea to consider!
Try to contact the european comrade tankers
in:
and see how they got ahold of these large
motors.
However, if you cannot find motors you can use
cordless drills , like Joe SOmmer initially did for his Hetzer http://rctankcombat.com/tanks/T010/Page2.html
These are 12V drills, but you can find cheap
Chinese (about 50 euro each) 24 V drills, with 1440 rpm on the chuck. They can be found in Praktiker european multi-mega
stores. When you reduce this speed to 500 rpm, the speed of the tank in scale
1:6 will be about 7-10 kms/h while the torque will be tripled! These drills have
two gears/ speeds. The low gear gives you 550 rpm. You will have to devise
your own differential though, or find one that is readily available in places or
factories that sell gears.
If you bust them, you pay 50 euros and buy new
drills. I never did have to do that (Makita drills cost at least 250 euros
each. Makita 12V motors alone cost 40 euro each and the gearboxes about
50!!!)
One disadvantage of cordless drills is that they
get heated very fast, but you'll have to live with this or devise an
effective cooling system: fans and aluminium sinks. If you drive your tank
in a cold weather, with temperatures below 10 degrees C, the motors will cope
with the heat. That's if your fans blow air with a temperature of 5 o C
and the entire hull is also cold. Think positive: Luckily, Norway is a cool and
convenient country to drive these little monsters!. Perhaps all of you comrades
think this is funny, but the motors don't cool down as effectively in a heat
wave and I know this from experience. How good are fans that blow air with
a temperature of 35-40 deg. C onto your motors? You will also discover
that without an opponent, driving an RC tank for about 20 minutes is
a lot of time, so there is no time to burn the motors. My motors, run with 6
Amph, once got so hot, that the little paper and plastic tags on one of them
(with type, voltage etc) actually burnt. I saw the smoke and panicked !!!
Nothing happened to the motors though I replaced one of them later, just in
case. Use batteries with few Amph ( 3.6) that you can change quickly with new
ones, so the drills' motors won't burn.
I am just saying you should always see the glass as
half full, build your own tank whatever it takes, take advantage of the
opportunities and see the compromises as "adoptions".
CHrys
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