Re: 80/20 Inc.
 

967 uses 20x20mm and 20x40mm Bosch extrusion, and like 341 we often tap the ends for 1/4-20 for making corner connections. We like the 5 mm block nuts and small corner gussets. We sometimes use 10-32 screws in the M5 block nuts, because they fit nicely, and we have lots of 10-32 hardware. For the last three years, we've used a kit frame for the drive with Bosch structure coming up from there. In 2009 we also made the drive base out of Bosch, but that consumes a decent amount of precious time compared to tossing a kit frame together.

The sliding block nuts are pretty nice sometimes. For example, last year our shooter used a pair of 20x20 extrusion rails as fixed ball guides. Before we built it and played around with it, we didn't know the exact angle or distance from the wheel that we'd want, so it was nice to work with an easily adjustable mechanism.
http://www.flickr.com/photos/lmrobot...in/photostream

T slots and block nuts can only handle so much force, and if you exceed that the T slot edges bend outward, allowing the nut to come free. So when something is going to get loaded up, you have to drill it out and bolt it through the extrusion.

We used to build frames out of 30x30mm and 30x60mm extrusion, but we switched away from that because it's heavy. 20x20 mm is a nice FRC size.

It would be cool to prototype with Bosch and then transfer the dimensions we come up with to a lighter, tighter sheet aluminum design, our team has a ways to go before we'll be able to manage that sort of design cycle within a 6 week build season.

Re: 80/20 Inc.
 

2363 has a presentation we give on how we use 8020 in our frames in a weight efficient manner. I've tried to upload it as a white paper, but this doesn't seem to work. The file may be too large. You can see the presentation here.

Our 2011 robot:


Our 2012 robot:

Re: 80/20 Inc.
 

We love it.

It's easy to work with, easy to change around, doesn't bend or deform (that I know of) and we seem to have a lot of it lying around.



We even used it for our pit:


It's kind of on the heavy side, but we feel it's worth the extra pounds.

Re: 80/20 Inc.
 

Hey, us too!

Re: 80/20 Inc.
 

Thank you everyone for your comments, suggestions and ideas!!!! I will get some 80/20 and look at some of the other materials you all have suggested.

This will hopefully get us through the first year. Right now we have 18 interested students and only 5 have done FIRST before for which 2 are programmers, and in the "building team" 2 have 1 year experience and 1 has 3 yrs exp. I hope to have everyone prototyping immediately and try to get some depth with knowledge and fabrication experience as soon as possible. I'm hoping for "Fail sooner to succeed sooner"... a slogan used by IDEO

If anyone else has ideas on how you used it that would benefit this young team, please let me know.

Thanks again for your help, the FIRST Community is the best ever!

Re: 80/20 Inc.
 

Thank you everyone for your replies!!!

The FIRST Community is the best!

Trish
Parent Volunteer and FRC2240 Team Mgr.