Today I gleefully added the carcass of Copperhead 2 that had been rusting away in my garage to the scrap metal pile that has been accumulating in my trunk, ready to be taken over to Scrap-All. You can see how bent and beat up it looks (and is!) - and from only two battles. Yeahhh... we don't really like to talk about 2007...
This photo shows the battery mount bracket - full of holes and covered in black duct tape - which we need to eventually replace. It is not high on our list of priorities as it withstood last year's competition fairly well, but I think we should aim for something more durable than 6061 aluminum that is full of holes. Weight is still an issue, since every repair I've made has added something to the 120.4 lbs we squeaked into competition last year.
These show the four new front corner support posts I fabricated last week. They weigh .47 lbs more than the old ones did, with screws, but the screws need to be shortened by over half an inch. Overall, I think we
can take some weight out of these by drilling holes through their centers as well. The mounting system is slightly different than last year's round post with a screw through it and floating nut inside the frame tubes. They are secured by two 5/16 - 18 button-head screws, one is the same as the inside front corner of the gearbox, the other fitting into a slot milled into the front of the supports so that the hole spacing discrepancies can be accounted for. I also ordered plain steel nuts (not stainless
or galvanized) to weld to the inside of the frame tube so we don't have a floating nut.The wheels were the main casualty of last year's competition, requiring serious welding TWICE - they practically disintegrated. We knew going into the competition that they were our weak point as they were exposed, and made from cast aluminum, but this year, we have already purchased 9 inch high strength polyurethane tires bonded to aluminum rings that we need to fabricate a wheel around. Ideally, I am hoping for a thick aluminum plate CNC milled so it's got a solid backside, but spokes around a hub on the other, and a titanium front plate to cover the entire wheel. I will add a blueprint once I have it drawn. The 4 tires (2 extras) we bought were a little over $600 total cost, fronted by my dad, Jeff. I'm hoping for it to be reimbursed out of our school account once our fundraising is under way... the material and machining cost for the rest of the wheels looks like it will bring total wheel cost up to near $1000. They should ship friday (monday at the latest) and I'll get my wheel design done asap so I can check WHEELS off the Copperhead list. The other thing that needs to get done that is vitally important to getting Copperhead functional again is the motor bracket mount, which I'm going to make out of the extra chrome-moly tubing we had left over, and weld it to the existing tabs from last year's aluminum mounts. That will definitely be the next thing I do...
For now, I'm going to see what happens once school starts. Meetings are likely to be tuesdays, 6th period in Dr. Skipper's room, but I don't know for sure. Definitely no meeting first week of school, but check back here later for our meeting schedule.
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