Bishounen

Hey guys.

I'm kina new here (first post) so I hope this is going into the correct forum. But anyways, I am really hoping the experience RC modelers and builders here can give me a leg up on a Mod I am researching.

Before I get into what I am attempting, I feel I should give some background. I spent most of my child and teeage years working with models of varying types. Starting with simple plastic models and then moving to model rocketry. Eventually I got into RC models, but that was right before I hit my late teen years, and got involved with other things. I still have my old Tamaiya Grasshopper though. Stored in it's original box and still functional. Since those days I grew up, got married, and had kids. Both my kids turned out to be special needs kids, and so taking care of them is my primary focus. However, This doesn't mean I don't take time for myself, and finding ways to include my kids is always fun. That is what this mod is all about...

Essentially what I intent to do is to transform one of those Fisher Price Power Wheels jeeps into a Giant RC Truck. I intend to keep the seats and the saftey systems, since my kids will be riding in it, and I would prefer to keep the current drivetrain and battery power source (for safety and cost concerns).

Here is what I figure I will need;

At least one high torque servo to operate the steering function
A speed controller to override the current electric controls
a new receiver and crystals for my RC control unit
replacement rims and tires (currents ones are one-piece plastic and wearing out)

Currently, I think the biggest challenge is getting the steering working. The electric speed controller shouldn't be that big a deal to disassemble and modify, But the steering is curently a direct-steer wheel, gear and rod setup. Which means it takes a good amount to pressure to steer, especially when the truck is not moving and loaded down with two kids. Obviously most of the standard servos wouldn't be nearly strong enough to operate this kind of setup. What I am looking for is a 12 volt high power high torque servo I can use as a steering controller, or perhaps an electric motor and servo controller combination unit.

What would you guys suggest? I don't have the funds to afford trial and error with piles of servos. I need to get this right the first time.

drevil

My Feedback: (5)

I've seen a guy do something similar in RCCA Magazine years ago, he built a full metal frame and put a lawn motor engine in it and used lawn tractor tires.

As for the speed control, that shouldnt be too big of a problem as most of those fisher price cars use a small motor similar to what you'd find in stock r/c. I'm not 100% sure but they actually might be a 540 type of motor. Either way you would just need to find an ESC that works with a 12 volt system and that can handle the load that size vehicle will put on the motor.

As for the steering that will be tough because as you said your kids will still want to ride it. Did you plan on riding them around in using radio control, or would they still be able to ride it all by themselves? The problem i see with them being able to still ride it is with the steering setup. If you hard connect a servo to the steering and then let them ride it around it's likely that the servo will be toast in no time as it will be moved back and forth while they steer the vehicle.

EDIT:
I was just thinking of something else. If you plan on putting rubber treaded tires (like gokart or lawn tractor tire) I think you'll find that the stock motor setup will be way to underpowered and not durable enough for those tires. So you might want to plan on a totally custom drivetrain.
Heck, while you're at it you might as well just throw a G230RC in it

fourwheeler

Now that is what I am talking about!!! You said you were keeping the stock safety systems in the Jeep??? What about a Harley-Davidson V-Twin with a wicked set of pipes and maybe since you are building a complete drivetrain then go all out and slap in a tube frame with a 5-point harness setup. Be sure and put floorboards in the thing and utilize the 5 speed gearbox from the donor Harley and maybe a parachute system......Halon fire suppresant system....fuel cell......remote kill switch.......

kengentry5000

My Feedback: (2)

A sister company to mine has industrial servos. I don't know who the distributors might be to sell you just one motor or how expensive it would be but here's a starter link:

http://www.danahermotion.com/

Ken

Bishounen

I was planning on disconnecting the steering wheel from the linkage and just keeping it connected as a dummy wheel for the kids to play with. I live near a pretty busy street and there is no way I want them steering.

Basically I'm going for the total control setup, they just ride along. Great for when we go on "walks" as I can keep them strapped into the Jeep while I walk alongside controlling it with the remote and doing the steering. They won't get much exercise, but I won't have to fight them the whole way as they want to run off in every direction at once regardless of traffic conditions.

Maybe If we move to a better location as they get better at operating things like this I can look into having a switchable setup. Perhaps use an electronic control on the wheel instead of a physical connect (drive by wire, as it were) That way I can swap back and forth from kid controlled to parent controlled.

Rampede

the stock motors in the powerwheels are 550 size they are the same exact thing as titans well they used to be im not sure about now, you should buy new motors like a 27t or a stinger 20t i did that and with my sister 120lb it hauled ass lol.

jimbo1890

I have a thought regarding the steering but you need a little mechanical and electrical knowledge.

why not use a windscreen wiper motor and gearbox to provide the steering force and use a normal servo to control two switches one for left one for right ie just reverse the polarity. you would not have self centering steering but if you are only putting around to give the kids a bit of fun that's not really needed.

You could also make up a simple speed controll the same way

The cam wheel on a standard servo throws a microswitch which controlls a relay which runs the motor.

I can draw a cct diagram if needed.

We used to make our own mechanical speed controls using standard servos and large 10w resistors.

OLD_SLOW and in the WAY

steering........... take a look at the actuators used for hot rods, they open doors trunks push antenaes up etc. or how about the works from an eletric car antennae they have a lot of power

fourwheeler

Aren't both of these options rather slow in operation?? I would think you could make up for the loss in speed with the correct bellcranks.

drevil

My Feedback: (5)

Scratch that. If you are going to put all of that money into it, then might as well go with Suzuki Hayabusa engine with a turbo setup. Of course an extended tube frame, jr. dragster tires, and a roll cage would be a must but i guarantee you will have the fastest powerwheels around...LOL