pic: Drilled out gears

[dlavery]

Very nice weight reduction efforts. But just remember not to be TOO aggressive about removing material - it is possible to take a good thing too far. I always like to remember this image from last year:




-dave

[EricH]

I'll agree with Dave. We had drive sprockets last year and took a little too much off. They broke in post season with more events to go, so we had to replace them.So I'd say that if you must lighten a gear, do it a little at a time, preferably only if you are over weight or planning to be (in which case, the robot will start looking like swiss cheese).

[Bharat Nain]

Hey we drilled holes in our wheels to reduce weight. It wasnt noticable, but it worked, and they were still reliable.

[Paul Copioli]

FYI, Jon V-Neun consulted with me before his team modified those gears. I did a quick Finite Element Analysis and told him he could take more material off if he wanted too. The two big areas of concern are the area near the hex shaft and the area near the gear teeth.

John,

That is a really cool pattern, by the way.

A comment about Daves Picture:

The main problem in the picture is that there are only two spokes holding the sprocket to the hub. That is an unstable solution. They could have gone with 1/3 the spoke width and added a third spoke and been fine. Notice the failure mode is in the bolt twist direction. A third spoke would have made it much more rigid/stable.



-Paul