Frame Perimeter Tolerance

[Al Skierkiewicz]

The recommendation from experienced (OK Old) mentors is to build to 1/4" under in every dimension. Tolerances in bending are finite and they could be too big. Whatever way the Inspection team decides to measure the Frame Perimeter, it better be less than 112". The guideline is using a 112" string wrapped around the robot frame. Boltheads, welds minor protrusions are different than a misplaced bend, angle stock in the corner or a transmission that stick outs from the frame. We call this practice "playing with fire".

[cgmv123]

I hope it never comes to this, but remember that the pits (especially the ones at Championship) can be rather toasty. Aluminum expands 12.3E-6 inches for every extra degree Fahrenheit. If your build space is rather cold like ours is (~60° F), and the pits are ~76° F, a 28x28 inch robot could gain 0.0220416 inches in its perimeter. That could cause you to fail inspection. Build smaller on purpose!

(The calculations in this post are intended as a thought exercise and are not intended to be scientific.)

[kevin.li.rit]

[quote=DevenStonow;1331383]

Originally Posted by amesmich

28" inches is 28" regardless of whats on it, however they do say things that protrude out like nut ans bolts < than 1/4" are ok so I would bet it would be ok, but thats just my bet. I would think that if you asked they would say what I said in my first sentence.
/QUOTE]

In regards to this, previously, I've had the "issue"(ie. it wasn't really an issue) where the LRI further clarified that that rule is simply there in respect to your own FP-ie. if you're 27.5x27.5, those protrusions are okay, but if you're 28x28, they would NOT be okay, because (as said in other posts) 112 inches is 112 inches, so no matter what you still need to fit under the 112 inches-including protrusions.

Keep in mind, this was just one LRI's interpretation, but I assume it'd be fairly consistent across the board.

Was this issue when they still had the sizing box and the size limit of 28"x38"? Because back then that was the correct interpretation.

[Steven Donow]

[quote=kevin.li.rit;1331449]

Originally Posted by DevenStonow

Was this issue when they still had the sizing box and the size limit of 28"x38"? Because back then that was the correct interpretation.

Yes, this was 2012. So yeah, maybe since then that is a different interpretation (I didn't read into the exact wordings in the past manuals)