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Re: Scores B/C

Posted: January 28th, 2015, 6:31 pm
by someusername
Would balancing the bucket even be that big of an issue? As long as you can prevent swaying of the chain/bucket, wouldn't all the force still be transferred through the chain regardless of if the sand was balanced inside the bucket? I personally have never had any issues with not having the bucket perfectly balanced, so I am mildly curious if it does make a difference

Re: Scores B/C

Posted: January 28th, 2015, 6:37 pm
by KayHill
someusername wrote:Would balancing the bucket even be that big of an issue? As long as you can prevent swaying of the chain/bucket, wouldn't all the force still be transferred through the chain regardless of if the sand was balanced inside the bucket? I personally have never had any issues with not having the bucket perfectly balanced, so I am mildly curious if it does make a difference
I also have never run into that issue, regardless it is simply something I observed while watching competitors before our group in that the ball bearings would all roll to one side the bridges seemed to lean towards that one side and break. However, I doubt other competitions besides MIT would use ball bearings at all.

Re: Scores B/C

Posted: January 28th, 2015, 6:40 pm
by nxtscholar
This was a topic discussed last year in boomilever. Yes, you're right. I forgot the exact wording, but once a sufficient amount of sand (or whatever you use for weight) has been poured into the bucket, it doesn't matter if the sand isn't level. It can be tilted because in the end, all the force will be acting downwards in that one point (the loading block). Would it be slightly different for bridges? I wouldn't think so.

As you also noted, you would want to make sure the bucket isn't swaying initially (this becomes less of an issue once more sand is added into the bucket)

Re: Scores B/C

Posted: January 29th, 2015, 7:41 am
by dholdgreve
Regarding bucket shift... The biggest danger of the bucket rotating when loading is not that it puts unequal load on the bridge, but that by rotating, the bottom edge of the bucket rotates and may touch the floor... If this happens, the event coordinator can stop the process and pronounce you as "finished" even though you barely got started, and the bridge is still in one piece. The moral of the story is:
1) Hang the bucket plenty high, so that if it does rotate, it won't hit the floor
2) If the bucket does start to rotate, don't fight it... I have seen far more bridges break due to the holder fighting with the bucket to keep it straight and in the process, push the bucket far off to one side... Don't panic, give it a few seconds and it will probably correct itself, and even if it doesn't, there is no real harm... I mean, what is it going to do, pull harder on one side of the chain that the other?
3) Be very careful during your set up that the S hook of the chain is centered on the bucket bail (Handle), and not off to one side. If it is, when you start loading, it may slide back to center which can cause a dynamic shock load that you really don't want or need.
4) Be careful during your set up to check the chain for any kinks in the links... Sometimes, chains will get this funky twist in them, and when you start loading it will pop out, again causing a drop and dynamic shock load
5) And while I'm on the soapbox, If you are using a loader, open the gate slowly, but once the sand flow is established, open it up wide open! Get as much sand from the loader to the bucket as smoothly and quickly as you can...

Re: Scores B/C

Posted: January 29th, 2015, 10:39 am
by iwonder
dholdgreve wrote:5) And while I'm on the soapbox, If you are using a loader, open the gate slowly, but once the sand flow is established, open it up wide open! Get as much sand from the loader to the bucket as smoothly and quickly as you can...
And that's why loaders, if you've practiced with it, are the best things ever :P

Re: Scores B/C

Posted: February 9th, 2015, 4:24 am
by ckssv07
Does anyone know the top scores at Wright State because our middle schools bridge had a fairly good score but the proctors did the math wrong and they ended up getting 37th. We just want to know approximately where they would be in terms of rank.

Re: Scores B/C

Posted: February 9th, 2015, 5:05 am
by chalker
ckssv07 wrote:Does anyone know the top scores at Wright State because our middle schools bridge had a fairly good score but the proctors did the math wrong and they ended up getting 37th. We just want to know approximately where they would be in terms of rank.
What do you mean 'they did the math' wrong? I have all the raw scores for Wright State since I ran scoring there and can look things up for you, but I'd like to understand your comment.

Re: Scores B/C

Posted: February 11th, 2015, 7:05 pm
by Friedoyster3
chalker wrote:What do you mean 'they did the math' wrong? I have all the raw scores for Wright State since I ran scoring there and can look things up for you, but I'd like to understand your comment.
Chalker, do you happen to know if raw scores from Wright State are going to be publicly released? I competed there, so I obviously know my own score and rank, but I'm sure a lot of us would like to know just exactly what the score spread amongst the top teams was.

Re: Scores B/C

Posted: February 12th, 2015, 4:35 pm
by chalker
Friedoyster3 wrote:
chalker wrote:What do you mean 'they did the math' wrong? I have all the raw scores for Wright State since I ran scoring there and can look things up for you, but I'd like to understand your comment.
Chalker, do you happen to know if raw scores from Wright State are going to be publicly released? I competed there, so I obviously know my own score and rank, but I'm sure a lot of us would like to know just exactly what the score spread amongst the top teams was.
I believe they are available for download along with the rest of the tests / answer keys at the site all the coaches were given access to.

Re: Scores B/C

Posted: February 13th, 2015, 5:48 am
by dholdgreve
chalker wrote:
Friedoyster3 wrote:
chalker wrote:What do you mean 'they did the math' wrong? I have all the raw scores for Wright State since I ran scoring there and can look things up for you, but I'd like to understand your comment.
Chalker, do you happen to know if raw scores from Wright State are going to be publicly released? I competed there, so I obviously know my own score and rank, but I'm sure a lot of us would like to know just exactly what the score spread amongst the top teams was.
I believe they are available for download along with the rest of the tests / answer keys at the site all the coaches were given access to.
Unless they were uploaded later, only test type answer keys were made available in the coach's email. A summary placement was included in the hard copy envelope, but no raw scores were furnished.