Field perimeter problems / bad zip ties at greater Pittsburgh regional

FIRST General Forum
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I was at the greater Pittsburgh regional this weekend and in two of our matches and at least one other match there were field faults due to a polycarbonate wall section having zip ties break and falling out of place. I’m my 5 years of first I have never seen this happen and am wondering if these field perimeters are starting to show their age or did first cheap out on crappy zip ties.

I have included clips of when it happened to us, there was no damage to our bot and I have seen way worse hits with the perimeter resulting in nothing happening

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I don’t think I have seen full panel(s) fall off before. I have seen a heck of a lot of zip ties pop off and shoot into the air from the field.

I have also inadvertently come across plenty of bad/old zip ties. So it is quite possible some got mixed in from somewhere.

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I think the intake side panel caught the edge of the polycarb. I was a bit concerned about field reset taking an intake to the shin.

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Those are 50 pound not 100 pound zip ties on the field border, I see the 100 pound ties on the lower hub exits though. The difference is black and white.

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Those are not the current specification zip ties. They should be black, for years FIRST specified the 50lb natural for the side wall polycarb. Then in 2019 in response to a few side panels popping off it was double natural 50lb. For the 2020 season FIRST switched to 120lb black for that purpose.

Now it is possible that those are 120lb rated but since they are natural I’m guessing the person used the natural 11" 50lb units shipped with the field instead of the Black 12" 120lb that was in their supplies because they “always use natural on the side wall”.

I’m guessing the reason they used to use natural was so that they blended in and were not noticeable. The reason they are now black is so that it is more noticeable when they break so they can be replaced if one fails.

Source: I’m the one who purchases every zip tie used on the fields in the PNW district along with the other field consumables. Each field supply bundle should have had 750 12" 120lb Black, 800 11" 50lb Natural, 500 8" 10lb Natural.

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Looks like Smoky Mountains is having the same problem - they just had two matches in a row field fault for panels coming off. They just redid all of the zipties on the one side of the field, and looks to me like they’re all the natural color zips, not black like you mentioned.

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We had a panel come off after a particularly hard hit by a robot in Ventura, WK2. Not sure which zip ties were used, and it was the 2nd of back to back events for the field. Fortunately it was near the end of the match and robots were going to hang. We kept an eye on the missing panel ready to e-stop if anyone came near it.

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I’m sorry to hear that. If FIRST sent out what they told the PNW to use then yeah those are under spec 50lb units that should not be used on the side boarder polycarb.

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Overtightening the zipties can also affect impact strength results, but in a -5% marginal kind of way rather than a specification miss -50% kind of way.

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Well hopefully we won’t see this occur in week 6. I spoke with one of the Co Chief Field Supervisors about the issue and she’ll be putting a reminder to use the Black 120lb zip ties for the side walls in this weeks email to Field Supervisors.