Bw: Tmd.

Hello there,
This is a the build diary of my new bw melty bot, TMD.
So, it's going to have a welded 2mm titanium chassis, 3mm polycarb lid, 2 250w brushless motors, 4s 1300mAh LiPo, and a huge weapon bar:

Motors:
http://www.hobbyking.com/hobbyking/s..._version_.html

Lipo:
http://www.hobbyking.com/hobbyking/s...Lipo_Pack.html

These wheels (in 2", shore A45 and black):
http://www.fingertechrobotics.com/pr...o-wheel&cat=11

And this weapon:
http://i1280.photobucket.com/albums/...ps2892f122.jpg
http://i1280.photobucket.com/albums/...ps79bc9424.jpg
Yep, its a tree splitter thing
Please do let me know if I've made a huge mistake in the parrs I've chosen (not bought any yet)
John :)

How heavy is that bar? It looks hefty

1.2 kg according to the picture.

Looks good, and that bar should be deadly, but how are you going to get it in the weight limit?

If that bar really is 1.2kg, I'm sorry to say that you'll have no chance getting that in the weight limit. If you're modifying the bar, however, that might prove viable...

And the two motors you've chosen have an amp draw of 20A-ish each, which means 40A. Your battery will only supply 32.5 if my calculations are correct, so you might want to get a higher discharge rate battery if you're going this route. Probably a higher capacity too, I'd say - maybe 1500-2000mAh would be better.

I'm only going to use the front third of the bar

Got a CAD?

Motors seem usable although dual brushless setups can be a pain, might be worth just going for one more powerful motor and to echo what Matt said get a higher capacity battery and one that can supply more current than you need.

If you only use the front 1/3 of the bar, that's a lot more reasonable, just make sure you mount it strong because that's still a good what, 400g? Sure you already know that though.

Definitely use a bigger battery though, I feel that the one you've suggested won't cut it, both capacity and current-wise. You'll want it to run for a good 4 minutes at the most, I'd say - just to leave yourself some lenience so you'll never run out of battery in a fight. I'd assume you'd be running those motors at full pelt for the full 3 minutes of the fight so that'll require quite a beefy battery I'd guesstimate.

You're battery will be fine I ran a feather on a 1600mah pack n used to get 2 or 3 fights out of that :)