Project: Battle Truck, MGT 8x8
 

Ok guys, I have a feeling you're going to like this one. I've got a MGT on it's way (parcel post... UGH!) So it should be here late next week, probably thursday or friday. It's already been converted to brushless using a KB45 motor. Although, I'll completely be stripping down this MGT and using it for parts. I'm also working out a deal for a complete MGT 4.6 roller. RTR without engine. Here's the plan: I'm going to remove the diffs and put 4 outrunners in their places, all rewound to ~180kv for operation on 3s each. Yeah, that's right... 4 motors, 4 esc's, 4 batts. Here's what i plan on running on each axle:

http://www.hobbycity.com/hobbycity/s...less_Outrunner

http://www.hobbycity.com/hobbycity/s...Simple_50A_ESC

http://www.hobbycity.com/hobbycity/s...idProduct=6501

RX pack:
http://www.hobbycity.com/hobbycity/s...idProduct=5552

Here's what I got for the operation:


Differential Ratio: 1
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 1
Pinion Tooth Count: 1
Total Voltage: 11.1
Motor KV: 180
Tire Diameter (inches): 7
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0
Spur/Pinion Ratio: 1 : 1
Total Ratio: 1 : 1
Tire Circumference (inches): 21.99 inches (558.58 mm)
Total Motor Speed: 1998 RPM
Vehicle Speed: 41.61 mph (66.84 km/h)
Estimated Adjusted Speed: 39 mph (63 km/h) - 5% loss
Effective KV Value: 180
KT constant: 7.51 oz-in/A
Motor Torque: Amperage not specified...
Final Torque: Amperage not specified...
Final Power: Amperage not specified...

I think this will be a fun setup, to say the least. Input? Oh let me get to the firepower.
I was thinking one of these because it fires at a decent FPS, and holds a lot of ammo, as well as it looks like there is alot of plastic that can be removed.
http://www.walmart.com/catalog/produ...ct_id=10248640
Also, going to do a rotating rocket mechanism, mounted to the top of the cab. I'll get some pics when the first MGT gets here. If you have a complete rolling chassis MGT for trade for BL stuff shoot me a PM!!

Looks awesome dude, should be pretty crazy! Cant wait to see some pics of it!

Thanx! Can't wait either.

You will need to take lots of pictures of this! How do yo plan to set up the wheels and the steering?

The outrunner will (hopefully) directly replace the differential without too many issues/modifications. The motor shaft will come out both sides equally, and I'll probably have bearings supporting them. The shaft will mount into the CVD joint right where the differential shaft would've gone. Steering will not change at all from the stock setup.

Braking?

Should be a very interesting project indeed.

Reverse mounted ducted fan...

I would run a direct to diff setup with one outrunner for each pair of diffs. I assume you will run a steerable wheel setup at the front and rear, and have 4 wheels in the center close to each other. That way you could run a 6s compatible 4130 size outrunner (pair of them) and a pair of MMM's for full foward/reverse/ and brake.

This will be a heavy vehicle, but will require a minimum of fabrication. Just make a center piece that will attach the two trucks together via the skid plate area, with the back, non steerable wheels together. You will also need some sort of upper brace to tie the top of the bulks together, but flat stock should work fine. Steering could be handled with a simple y cable, as the steering wheels will have to turn opposite of each other to pivot around the fixed wheels in the center. Making decent motor mounts will be important, and supporting the non mount end of the outrunner with a bearing is a decent idea.

Braking, I was thinking just drag brakes set to 100% for each ESC. Thanks for the kudos.

No, I'm going to have 1 full MGT in the front, and then 2 axles behind it. I was going to use 2 outrunners, but I'm not sure if Mike could make the dogbones for me. I'm making the conversion all myself, because I'm getting a mill in a couple weeks (last year's xmas present from dad that hasn't been purchased yet...) Linc, what was that 1 servo-reversing y-cable that you used on your x-factor? I want one to use for the steering. I want to go HV on this project, because lutach gave the virus and now I can't go back. If I go with 2 outrunners, I was thinking something along the lines of these components:

http://www.hobbycity.com/hobbycity/s...utrunner_235Kv
http://www.hobbycity.com/hobbycity/s...imple_100A_ESC
http://www.hobbycity.com/hobbycity/s...idProduct=7639

Differential Ratio: 3.3076923076923075
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 1
Pinion Tooth Count: 1
Total Voltage: 22.2
Motor KV: 235
Tire Diameter (inches): 7
Tire Ballooning (inches): 0.5
Motor Current Draw: 0
Motor coil Ω: 0
Spur/Pinion Ratio: 1 : 1
Total Ratio: 3.30769 : 1
Tire Circumference (inches): 25.13 inches (638.37 mm)
Total Motor Speed: 5217 RPM
Vehicle Speed: 37.54 mph (60.3 km/h)
Estimated Adjusted Speed: 36 mph (57 km/h) - 5% loss
Effective KV Value: 235
KT constant: 5.75 oz-in/A
Motor Torque: Amperage not specified...
Final Torque: Amperage not specified...
Final Power: Amperage not specified...

Here's what I plan on doing for a RX pack:
http://www.hobbycity.com/hobbycity/s...0C_Lipoly_Pack
http://www.hobbycity.com/hobbycity/s...w_Voltage_horn

:gasp: Wow.. this is going to be a fricken GREAT build to watch..:yipi: best of luck with it.. :intello:

Hay BL..:whistle: can you post any pictures in Project X threads ??:neutral:? I still cant..:no:

anyway looking forward to future updates.. :yes: :yipi:

Hope to see you tomorrow.. (I've got a six pac of soda with your name on it) :wink:

Thanks!
I can't wait to see it come together. What's say we have a formal all-out battle at the november bash??? Weapons allowed, last truck standing wins! How's that sound? I'll try posting a random picture:

http://i10.photobucket.com/albums/a1...r/pichers1.jpg

No dice. I had [IMG] tags around it and everything.. Weird.

sweet, i cant wait to see how the motors fit in the diffs

If you look at the bottom left of the page you will see the img code is off on this sub forum. Pm BrianG and see if he can switch it on...

At this point I have no idea whether I'm going with 2 motors or four. I'd *like* to do the 4 motor setup, but it'd be a lot cheaper to go with the 2 motor deal.