We only have three days of build time left before hitting the road for Motorama 2012, and we still have two unfinished 'bots. Today we decided to concentrate on the one that has the most work to be done: Palindrome30, our Sportsman-class thirty pounder, and see how far along we could get. Hit Back after viewing an image.
We're starting out today with some disassembly, as we need to be able to get the baseplate drilled for motors, etc. There are a lot of bolts on this 'bot! But thankfully only eight to be able to get at the batteries.
We've ended up using buttonhead bolts for the outer blade brackets, because we couldn't get the countersink into the groove to be able to use flathead ones, so we need to make recesses for clearance. As the side panels are 15" long, we can't do this on Milly, but we can put a half-inch endmill in the drill press and get the job done.
They actually came out quite well, once we got the hang of shimming the wall in the slot on the side of the drill press table. One more thing to cross off the list.
This was a test to make sure the clearance holes were deep enough - it all looks good, so time to move on to mounting things on the baseplate.
But first a weigh-in. Despite the copious number of bolts in this 'bot, we're still way underweight at the moment at 26.0 pounds. Granted we do need to throw in eight hubs for the saw blades, but they're only going to be πr2 x l x density, or 3.14 x 0.625 x 0.625 x 0.375 x 0.1 = under an ounce each.
After marking and drilling the baseplate, we have the DeWalt drive motors in place. We also drilled mounting holes for the weapon motor mounts.
It's pretty chilly again today, and we had the heater running, which did a good job of warming things up, but this also warmed us up: forcing an 1/8" broach through a wheel hub - darn, that was hard work! Two down, two to go, and we'll come back to them in a bit.
This shot was taken after carefully tightening the weapon brackets, and getting them all aligned. The shaft actually spins fairly freely, which is great!
On the internals, and here's a test layout. It's fairly cramped in here, but that's a good thing - it'll stop components from bouncing around inside the 'bot. On each end we have a weapon motor and drive speed control, next in are the drive motors, and in the middle we have a 4S weapon battery, two weapon speed controllers, and two 3S drive batteries which will be linked in series for 22.2 volts. There are two separate power switches, one for drive and one for weapons.
The two power switches have been mounted to the side wall, to get the hex hole as close to the top panel as possible, and leave room underneath for wires to pass by.
The top plate has been drilled for access holes to the power switches. We're not going to paint the top, so the LEDs on the Victor 883s will serve as our power lights, saving us from having to cram another component in there.
The drive ESCs have been mounted, and we're beginning to wire things up.
We didn't pay attention to the batteries when we selected them, but these packs have 8 gauge wire on them. We don't have any connectors that fit that size of wire well, and after struggling to get Anderson Power Poles on one of the two packs, we finally gave up for the night, intending to mull over what sort of connectors we can use, and come back tomorrow with a solution!