Quote:
Originally Posted by pilum40
Dr. Joe:
I'm the coach for Team 3355 in Arlington, Texas. My team is frankly open mouthed about Boom Done. We did have a couple of questions please...for now... 
1. When you use "green cord" in your shooter", what kind of cord do you use? Did you custom make the pulley for this cord or is it off the shelf?
2. What was the gauge of wire you used for your catapult/shooter? Did you hand form it or have it made?
3. What was the material you used for the "Toro Horns" please? We have a running bet (lunch) that it was rough sports tape or something similar. Please let us know, we're all hungry!!
Thanks in advance!
Steve Miller-Coach
The Purple Vipers |
Green Cord. It is the
metric size solid core urethane round belt on this page from McMaster I use a ton of the 6mm (8112K33), but the 4mm stuff is also great. Run it around the pulleys to get a free length, cut the belt 3-6% short, use a lighter to melt the end (act like you are making a golden brown marshmallow), press together the ends, hold til cool, trim the joint with a side cutter. It is a REALLY useful way to spin something at a distance.
Pulleys are laser cut acrylic 1/8th thick. We cut a ton of these with a "FIRST standard" bolt hole pattern 1/2" increments. We then can stack up plates to make pulleys. These are not just good for actual robots but especial for prototyping.
Loop Gauge of wire is 1/4" steel. We had it laying around the shop.
Toro Horns. You are not going to believe it: Schedule 80 PVC (thicker wall than Schedule 40). I heated up some 1/2" hex shaft and melted it in place so that a Versaplanetary shaft fits tight inside.
Dr. Joe
* which roughly stated is (6) #10 holes on a 1.875" bolt circle with a 1.125" center hole.