pic: Rastogi 8wd Iteration 1.2

[Jamie Kalb]

Originally Posted by RMS11

Where here would you attempt to use PEM nuts. I was looking at them on mcmaster, and they look cool, but pressing all of them seems time consuming when you could just use rivets or a nut and bolt instead. In the long run it might save a bit of time though... Any other big advantages of them? thanks!

I'm not good at judging measurements from pictures, but it looks to me like the current flanges aren't big enough. But if the flanges bent off the main body of those enormous side plates were wider (or is that longer?), you could punch holes in them and press the PEM nuts in. As far as I know, many sheet metal shops can do this in-shop. Check out the 217/148 Sheet Metal video. It shows them pressing PEM nuts at about 5:05 in the video. Not time-consuming at all. Compare the ~1 second per insert to all the time you'd spend fumbling for a nut ... total. For a season.

Whenever possible, I like to add threads to a part (tapping or threaded insert) rather than using a nut. One less piece to worry about, one less piece to come loose, one less point you have to reach for assembly/maintenance. Plus installation and removal now only takes one hand!

But Andrew's 100% right about this:

Originally Posted by Joyride_67_1902

Being on 1902 I can say that when the flanges are facing outward it is significantly easier to run maintenance on the drive train. Considering that the space you are working with is already very small it is difficult to get to all the components even on the robot we have this year. I can only imagine what it would have been like if it were the other way around, having that "obstacle" in the way would have made some points of repair for us very difficult especially when we had a master link failure at Florida.

Having the flanges bent in rather than out definitely does make drivetrain maintenance harder. It's possible to make the plates modular enough to justify this, but you're probably better off just keeping them facing outwards.