Boomilever B/C

[nxtscholar]

West Windsor-Plainsboro HS South (NJ) got second in their state. They got an eff. of 1200.

[ckssv07]

I think DW got 1700+. Not sure.

Our boom broke super early ~1100 I think.

You are from SAA right?

[Scioly99]

I haven't been to state yet, but at regionals I got 6th place with 1680 . I'm pretty sure they messed up when ranking the teams... after all it was a pretty bad regional. They have messed up consistently over the years, which is not cool, especially when there is a possibility that their mistakes could keep the team from advancing to state.

[S4BB]

We broke early due to a very simple part and ended up in second with a score of 1683 at the state competition.

[AJTheGreat1729]

x

I think DW got 1700+. Not sure.

Our boom broke super early ~1100 I think.

You are from SAA right?

Yep.

EDIT: Had Grayslake's boom gone to its full potential it probably would have taken first.

[bearasmith]

The first place score was 1330 for MD. We were 17 points behind it.

[inconspicuousmole]

How are you guys doing the struts between the tension members and compression base? My current design breaks around 12kg and looks somewhat like this. https://www.flickr.com/photos/123804914@N02/ Seems like the diagonal beams are pulling away from each other ultimately leading it to snap.

[JonB]

How are you guys doing the struts between the tension members and compression base? My current design breaks around 12kg and looks somewhat like this. https://www.flickr.com/photos/123804914@N02/ Seems like the diagonal beams are pulling away from each other ultimately leading it to snap.

I am going to assume you are using CA? Also, are you gluing them to the top of your compression piece, or side of the compression piece? Are your diagonals pulling away from the compression/tension piece or "each other" as you state?

[inconspicuousmole]

I am using tightbond 2. The struts are glued to the top of the compression plates with plates on the sides. It appears the struts are pulling away from the tension and compression pieces.

[iwonder]

It's definitely better to use CA(superglue). Wood glues require long dry times and clamping, which could damage really light balsa if you're not careful and really slow down the time it takes to build a boom. CA will be just as strong (if not stronger) and dry much faster without clamping, which means the odds of getting a good joint are a lot higher.

CA's also a lot lighter than wood glues.