Re: FRC Design- Tips, Tricks, and Effective Methods
 

I sure he was talking about circuit breaker tripping... the main circuit breaker is delayed action (lost the correct phrase), which means it takes few seconds after the current exceeds the limit (in this case 120 Amps). As I understand the main breaker responds to heat generated in due to high current. So it would make sense to cool the breaker before the next match. We have not done it.

Re: FRC Design- Tips, Tricks, and Effective Methods
 

Yeah, we ran into hard defense, and it wasn't an issue once. There was only one problem, and that was with some screws. It did't effect anything really.

Re: FRC Design- Tips, Tricks, and Effective Methods
 

I wasn't sure where to post this, but thought maybe a few teams would use it.

We are building an off-season drive train and were trying to find a way to drill aligned bearing holes through box extrusion easily. After trying a few standard hole saw sizes (1-1/8" & 1-1/16") that were either too large or not large enough, I found this item on Amazon: Link



After drilling a few holes tonight, we hit very close to 1.125" for our hole size. For 7 bucks I think this could be an inexpensive solution for a lot of teams out there that don't have the money or resources to invest in expensive hole drilling options. Plus they ship via Prime!

Re: FRC Design- Tips, Tricks, and Effective Methods
 

A holesaw? Be extra carfeul when using those. If you go in too fast, it will grip the metal instead of cutting. What is the spring for? And what is "very close"?

Re: FRC Design- Tips, Tricks, and Effective Methods
 

The spring is to push the cut circle out. A lot of times it will get pushed into the hole saw and it can be difficult to remove.

Re: FRC Design- Tips, Tricks, and Effective Methods
 

We use sleeve-style bumper covers on our robot, but still they stay on very well in defense. Doesn't seem possible that they could get flung off during a match, if you create them decently. Only problem I can think of is losing the bumper cover, which hapoened to us at our last off season, where we left it at our shop.

Re: FRC Design- Tips, Tricks, and Effective Methods
 

A little cutting oil and not trying to go too fast made this work just fine on 1/8" aluminum 2" x 1" box.

From a quick caliper check before I left, I read 1.125-1.127". So maybe not enough for a true press fit but I was pretty pleased. Our chuck also vibrates a little more than I'd like; with a better drill press you could probably hit even better numbers.

The spring sort of helped - but we did do thru holes on 2" x 1" aluminum box, and was able to easily get the discs out of the hole saw.

Probably not the ideal way to do these but if you're in a pinch or if you need a low cost option, I think it works pretty well.

Re: FRC Design- Tips, Tricks, and Effective Methods
 

That's really good tolerances. Like really really good. I don't think regular shelled insert holesaws can come close to that tolerance. We might consider buying one of those for causal use.

Re: FRC Design- Tips, Tricks, and Effective Methods
 

We figured out a pretty simple way to easily tension a versaplanetary gearbox tonight. This could be useful if you want to power an intake using chain or belts and want to be able to adjust the tension quickly. The gearbox can be mounted to the plastic bearing blocks that vex sells by adding a few holes -