Search found 30 matches
- October 4th, 2012, 5:10 pm
- Forum: Boomilever B/C
- Topic: Boomilever B/C
- Replies: 622
- Views: 118349
Re: Boomilever B/C
Balsa Man, The 2 mm was an estimate. I never "measured" the amount of looseness, but I can say without a doubt that the wingnut was pretty tight at the beginning and loose at the end. Thank you for the idea of using a wrench; when I tightened the wingnut, I just turned it until the bolt st...
- October 3rd, 2012, 4:43 pm
- Forum: Boomilever B/C
- Topic: Boomilever B/C
- Replies: 622
- Views: 118349
Re: Boomilever B/C
Speaking of testing boomilevers... I just tested a boomilever, and after it broke, I noticed that the bolt was pretty loose from the wall. As I added weight to the boom, the wingnut "unscrewed" about 2 mm. Is this normal? To me, it seems like trouble. By the way, my configuration was bolt ...
- September 17th, 2012, 5:06 pm
- Forum: 2013 Build Events
- Topic: Gravity Vehicle C
- Replies: 426
- Views: 89048
Re: Gravity Vehicle C
My ramp has wood sidings that prevent the vehicle from being seen if you are looking at the ramp from the side. Is this going to be a problem when the event supervisor tries to measure the height of my vehicle? I'm trying to think of an easy way to measure the height in my case but I can't think of ...
- September 14th, 2012, 6:17 pm
- Forum: Boomilever B/C
- Topic: Boomilever B/C
- Replies: 622
- Views: 118349
Re: Boomilever B/C
The part that makes me scratch my head is that the "center of the loading block must be between 40 and 45 cm from the testing wall for both Divisions." Why would there be a range (40-45 cm), instead of a minimum distance (>40 cm)?
- September 1st, 2012, 12:47 pm
- Forum: Boomilever B/C
- Topic: Boomilever B/C
- Replies: 622
- Views: 118349
Re: Boomilever B/C
Have you read this (http://scioly.org/wiki/Aia%27s_Boomilev ... Distal_End) yet? That's pretty much what I did on a practice boom and it worked great.fanjiatian wrote:How have you guys been connecting your tension and compression members?
If possible, draw a diagram (for my sake)
- July 26th, 2012, 7:34 am
- Forum: Towers B/C
- Topic: GLUE!
- Replies: 6
- Views: 6776
Re: GLUE!
I have data from a tower I built last season.
Tower without glue = 9.22 g
Tower with glue = 9.70 g
Glue = 0.48 g
So that's 4.95% glue by mass. I think this is reasonable, but not great, for a tower.
Tower without glue = 9.22 g
Tower with glue = 9.70 g
Glue = 0.48 g
So that's 4.95% glue by mass. I think this is reasonable, but not great, for a tower.
- July 23rd, 2012, 7:12 am
- Forum: Towers B/C
- Topic: Boomilever for 2013
- Replies: 142
- Views: 53354
Re: Boomilever for 2013
Wow, the discussion is getting interesting. I have a question, though. Will longer tubes hold less than shorter tubes of the same thickness and diameter? For example, iwonder said his tube was "3.75" long, weighed 1.2g and held 50kg before failure." So will a 16 inch tube (~40 cm) hol...
- July 21st, 2012, 7:12 am
- Forum: Towers B/C
- Topic: Boomilever for 2013
- Replies: 142
- Views: 53354
Re: Boomilever for 2013
With all this talk of large I-beams and tubular compression members, are you guys all assuming that there will be no limit on cross section? If I'm not mistaken, the last time boomilever was an event, the wood could be no greater than 1/4 inch high and 1/4 inch wide, with lamination allowed. Of cour...
- July 13th, 2012, 9:12 am
- Forum: Towers B/C
- Topic: Boomilever for 2013
- Replies: 142
- Views: 53354
Re: Boomilever for 2013
I was planning to have my compression member indpendent from the tension memebers, so the compression member doesn't buckle in any direction without bracing from the tension members, however I was going to put ultralight connections at the testing wall to maintain proper spacing, they wouldn't be s...
- July 10th, 2012, 9:24 am
- Forum: Towers B/C
- Topic: Boomilever for 2013
- Replies: 142
- Views: 53354
Re: Boomilever for 2013
Suppose a boomilever base was a solid, square piece of wood with a hole drilled in the middle and the tension members glued to the outside at the 3 o'clock and 9 o'clock positions. Would it be better for the wood grain of the base to run vertically or horizontally?