pic: Fun With Extrusion!

Don't ya just love 80/20? :stuck_out_tongue:

YES!!! we used it this year for the first time, and absolutly LOVE it. sooo easy to tension chain, move things that don’t quite fit, etc… See you guys at nats!

Holy crap, how long did it take you to tesselate those like that?

This would make an awesome wallpaper…

Makes me think of Dance Dance Revolution. Arrows arrows arrows!

Indeed, it does, lol. I got bored and tried to see what it looks like, but it doesn’t quite look right on my widescreen =

How do you use it to tension chain???

just curious because sliding the motors is a lil slower

If you’re using pillow blocks bolted to the T-slot, and not a through hole in the extrusion, you can slide them in the slots.

Its grown up legos.

One of my least favorite robotics related memories:
Tapping the ends of 15ish 80-20 pieces for our 2004 robot with some poor student (he was being punished, and I was setting an example for the other students).

What poor soul had to do all these?


This was also 1676’s first year using the extrusion.

Being on Mechanical and working with stuff i can say that this stuff is very easy to work with.

The only thing we had a problem with was with one of our drill bits for the universal connectors. The vice we had it in span around and broke the small part off. That was the last time we forgot the lube. :frowning:

this is exactly what we did. every loop of chain has at least one sliding component. kjhobin of Team 555 alerted me that 80/20 does not recommend this method, as the t-nuts are liable to loosen and slide, but we haven’t had this problem yet. Another option would be to add a tensioner sprocket to the t-slot and just slide that.

The nuts will almost definitely loosen themselves, everywhere on the robot (but particularly your wheels). We had this problem quite often in 2003 with all the robot on robot contact.

As long as you check your wheels and other critical structural members somewhat regularly, you should be fine.

come on John…just power tap them with the milwaukee best part of dynamic brakes

im still having trouble visilizing this (prolly cause it late at night since ive been up since early)but does somebody have a pic of this or a paint drawing?

Good thing it was a mentor who broke that bit and not some student…:wink:

Yes, and we ALL learned something that day.



The pillow blocks on the wheel shown have bolts going through them vertically, which screw into T-nuts in the slot in the chassis. By sliding the entire wheel assembly away from the center of the robot, the chain can be tensioned without a separate device.

this is the best pic we’ve got, but you can see the wheels are mounted on custom axel mounts. Later on the sprockets and chain were put on the wheels. The mounts can slide in the extrusion, and by attaching the chain and then sliding the mounts we can tighten or loosen it as we please.


One of our VERY patient mentors tapped all those pieces, about 20 if I remember correctly.

The sad part is we didn’t end up using them on the robot after all that work! :ahh:

Do you have a higher-res version of this? I’d love it as a background…