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Re: Boomilever for 2013

Posted: July 5th, 2012, 1:42 pm
by thsom
Quick question Aia, I was wondering the strength comparison of original super glue to the "purple" CA glue you used.
Edit: I was also wondering how you carved the interior of the base to accommodate for the tension members?

Thanks!

Re: Boomilever for 2013

Posted: July 5th, 2012, 1:44 pm
by nejanimb
Really awesome for you to put that together, and I think the result is great! Informative while still leaving plenty of room for readers to come up with their own ideas.

Re: Boomilever for 2013

Posted: July 6th, 2012, 6:52 am
by Aia
Faustina wrote: I don't think you're missing any major topics. However, one small detail I think you missed is the cutting tool (for the "tools" section). Specifically, I'm wondering if cutting basswood requires special tools.
I can certainly add that to my guide! For the record, the basswood sheets and sticks I used were pretty thin/small, so a regular exactoblade worked fine for these. I'll still address this somewhere in my guide.

thsom wrote:Quick question Aia, I was wondering the strength comparison of original super glue to the "purple" CA glue you used.
Edit: I was also wondering how you carved the interior of the base to accommodate for the tension members?

Thanks!
The only glues I used were two different types of CA and gorilla glue. I never used original super glue, so I'm not sure if I can help you out there. I guess I don't understand what you mean by "original super glue".

Carving the interior of the base was a skill I picked up after doing many of them. I started by drilling a couple small holes, then using an exactoblade to cut more out, and then meticulously used a small sanding stick to shape the hole perfectly. My first few carved out bases were pretty inexact, but then I got the hang of it as I did more of them.

Re: Boomilever for 2013

Posted: July 6th, 2012, 6:54 am
by iwonder
Awesome guide... Tons of stuff I haven't thought of yet, it will definitely be helpful to all of us, thanks!

And here's a random question... I guess we never had to think about it with towers(that's the only load-bearing event I've done), but how would one get the loading block in a position like this? Image Gallery is it legal to disassemble the block and then reassemble it? Other than that, I can't figure out how they got the block in there...

Re: Boomilever for 2013

Posted: July 6th, 2012, 7:23 am
by thsom
I agree!
Thanks Aia! When I say 'original superglue' I meant the super glue with the yellow packaging that says 'the original superglue' on it. But it doesn't matter because I was able to locate the purple CA glue.

Re: Boomilever for 2013

Posted: July 6th, 2012, 8:35 am
by twototwenty
Wow, what a great guide! The part about the different glues was particullarly helpful; I've always been somewhat unsure of which glues are best for what. Thanks so much for putting this together, Aia!

Re: Boomilever for 2013

Posted: July 6th, 2012, 8:51 am
by Aia
iwonder wrote:Awesome guide... Tons of stuff I haven't thought of yet, it will definitely be helpful to all of us, thanks!

And here's a random question... I guess we never had to think about it with towers(that's the only load-bearing event I've done), but how would one get the loading block in a position like this? Image Gallery is it legal to disassemble the block and then reassemble it? Other than that, I can't figure out how they got the block in there...
That's actually one of my very first boomilevers I ever built! My predecessor from 2007 built booms in this style, so I tried to mimic a few at first before trying other designs.

The only way I could get the loading block in there was to undo the nut, stick the block in, and then reassemble the loading apparatus. Honestly, I never built a boom in this style that scored very high. They were a nightmare to build, and a nightmare to test. My predecessor did manage to push this design to ~1000 or so, but that was with a lot of testing...

I never tested a boom like this at a competition. I abandoned the design fairly quickly. However, I did build a few bridges in 2009 that also required disassembling and reassembling the loading block. I was never was disqualified for this. You'll have to read the rules for 2013 boom to see what the standards will be. I'm 99% sure it'll be deemed legal.

Re: Boomilever for 2013

Posted: July 6th, 2012, 10:48 am
by iwonder
Great news... I really don't want to have to cut a huge hole out of my boom to fit the eyebolt :D Thanks again.

Re: Boomilever for 2013

Posted: July 6th, 2012, 12:37 pm
by nejanimb
Taking the eyebolt out of the loading block and reassembling has been okay (several top bridges a couple years ago did for sure, and I'd wager there were towers that did). Of course, at the regional level especially, you may run into supervisors who aren't as clear on this, so it's always good to get in touch with them in advance.

Re: Boomilever for 2013

Posted: July 7th, 2012, 1:00 pm
by fanjiatian
What are some equations that can be used to calculate the forces on each member?
Does anyone know of good truss analysis software?