rc car style?

[taintedplay]

ok, my case will probabbly be 100+ pounds, up to 350 (still working out batteries and such) on a pallet 2x3 feet. i was wanting to hopefully have wheels and a motor on it to drive it. only 2-3 mph. is that even feasible?

[billygoat333]

oh, its feasible. lol just depends on how much ya wanna work. just get an electric motor for a scooter or for a conveyor belt or something. will probably have to use a few deep cycle marine batteries for it.

[taintedplay]

well, two hundred of the pounds were from huge batteries already so i got the batteries, so would all i need is a scooter electric motor? or what?

[billygoat333]

http://www.monsterscooterparts.com/cu24v60hipem.html
this site has some interesting motors and such, here is one example.

you might need to set up some gearing but you could probably get away with a chain drive or a belt drive setup since you probably wont be taking your computers up hills and such. lol

as far as rc is concerned, I wouldnt know where to find a controller that could handle that motor, maybe someone here has some robot experience and can help you. :p

[crazybillybob]

to get the unit to go that slow you'll have to play with the gearing or use a speed controller.
My R2 fully loaded i 75 to 95 Lbs.... and at full speed can out run me at a fully sprint... not that I'm the flash or anything .... For safety I have those channels limited to 75% by my radio transmitter (that means at full stick the motors max out at 75% of there top speed). R2 is running 2 24V 100w Scooter motors (rated at 2500RPM), driving 6" pneumatic scooter tires, using a standard 5" rear drive gear. The Speed controller is Scorpion XL from Robot Power .com I've seen Droids of up to 250Lbs running on the same motor setup, but more weigh then that you'll need to rework the gearing as the power draw on the speed controller and motors gets unsafe (coils start to smoke and burn out easily)

If you going with the 250-300Lbs end of the spectrum your looking at something from the likes of NPC This kit has a motor, mount, wheel and gearing setup to do up to 12 MPH but it's not Cheap @ $160US. This type of setup will require a larger speed controller as well. These type of motors will draw up to 82 Amps when they stall!

Your platform well need 4 wheels, depending upon the weight distribution you maybe able to drive it with only 2 motors and 2 free spinning wheels. that's if the load is evenly distributed .... more then likely your looking at 4 motor wheel setups, and controllers .

I'm not sure how much fab, meta working experience you have or are willing to do! but it's possible that if you used 4 200 W (2500RPM)motors with the same 5.5" wheels (standard hard scooter wheels) you'd be able to pull it off...
Down side is your close to max @ 300LBs and if you plan to take this into a place for a LAN that has carpet (standard hotel conference room type) the hard smooth scooter wheels don't provide enough traction for it to move well and you'll blow fuses.

There are some 350W Scooter motors that run @ 750RPM with that and a little gear adjustment add some hard rubber 6" wheels (they sorta look like mini bike tires) and it's your best lower cost plan. Couple these with two of the Scorpion XXL (20A continuous per channel 40A max) you've got something that should drive you around.
If all else fails it would make one heck of an electric go-cart!!!

All the motor sizes, wheels etc. I got from here... electricscooterparts.com I've ordered from them before and got just what I needed quickly, and the prices are very competitive! If they have it in overstock it's the cheapest place to get it! and they have all the hard to find wheels (6" solid rubber threaded !!)

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[taintedplay]

i had a random idea, i was on harborfrieght and saw a winch that can pull up to 3000lb, at 6 feet a minuite for 70 bucks. since this thing wont be driving much at all, and in short bursts, i could get this, wrap it around the axle of the back wheels and tie it off. then when it starts to coil back up it spins the axle. it is 12v so i would wire it strait to the car battery im going to have on the platform. would i be able to use those same controllers to control speed?

[crazybillybob]

Knowing the quality of Harbor freight products (not knocking them I've got allot of tools from them!!) but I'm guessing it pulls more AMPs then these SC can handle. The other issue I can see is that you planed drive relies on the friction of the wire on the axle to drive the unit forwards. With as much weigh as you looking at, your either going to slowly cut the axle in half with the wire or the wire will just slip. Neither one is conducive to forward movement and both are bad for your very expensive custom mod that's riding on it


But +1 for thinking outside the box with the Fred Flintstone Idea . You keep thinking like that and you'll figure out a drive system!!!

[taintedplay]

explain the first sentence.

also, the end of the wire would clip onto the axle. and it would have a very thick axle so it wouldent be cut in half. its only 70 bucks, do you think using conventional motors i can move this thing even though it weights atleast 300lb and prob more for around the same price?

[crazybillybob]

Harbor freight sells low cost import equipment, this means that the motors used are not normally as efficient or as strong as similarly rated domestic products.
case in point I'm sure that a 3000LB Waren wench would use less power and last longer, and pull more the 3000Lbs with out damage then the Harbor freight one, but cost 4 or more times as much. This is mainly to save cost the import company uses a smaller motor and the 3000 Lbs is the max that it can handle with little to no margin of error. But it costs $70 and if I don't need to pull 3000Lbs every day all day..... It can burn out once a year, I'll replace it and I'm still saving money... And this isn't all ways the case, some of there stuff is built in the same factories as the name brands... and it works quite well... Like I said I own allot of there stuff, it's just that sometimes you get what you pay for

Also on the wench you have to factor in that the motor isn't rated for 3000Lbs. the Whole system is! when you use a wench you mount the block (a pulley with a hook on it ) to a tree or the other vehicle, then you run the line out through the block and attach it back on to the wench. the more times you do this the more weigh you can move with the same force.
So the max rating on a given wench is going to be the weigh it can pull when all the supplied blocks are used, and there s no additional resistance keeping the load from moving (Ie mud!)

The other thing about wench motors are there not designed to run all the time, just short bursts 20-30% duty cycle.. It's very possible that under the kind of operating conditions your looking at you'll burn them out quickly.

If your heart set on using the wench, your best option is to get rid of the cable. Replace the spool with a gear and put a gear on the axle for a chain drive system. no need for a speed controller just use the wench controller. the down side to this is you have no way to steer as both the drive wheels turn together. and it will take a heck of a motor to work as steering fro this set up!

My gut still says that the 300W motors are your best bet for the cost/ weight/ reliability.


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[BuzzKillington]

ok, my case will probabbly be 100+ pounds, up to 350 (still working out batteries and such) on a pallet 2x3 feet. i was wanting to hopefully have wheels and a motor on it to drive it. only 2-3 mph. is that even feasible?

What is this for again? You're making a 350lb RC car? out of your computer case?