So, here begins my build-a-bridge-in-two-weeks-because-you-didn't-get-around-to-starting-it-sooner marathon. I am such a procrastinator.
Ben, here is what I'm thinking about right now. If you could let me know your thoughts on the design, I would really love it. (I'll even make some more cookies for you when you come home again. :D)
You can click on the picture to enlarge it.
Basically I'm thinking that I'm going to go for a big, heavy (and hopefully strong) bridge this year. Fortunately, the weight limit is 30 grams instead of 25 grams. It'll help, but this is still going to be a scale-full.
I'm thinking of doing members 1, 2, 3, and 4 with fours (four wood pieces laminated together). Member 5, I'm thinking I can get away with using a two (two pieces laminated together), especially since it will only be in tension. That'll give me some good surface area at the top corner joint as well. Member 6 I think will probably be ok just being a single piece of wood (?), but I might want to beef up the corners where the bridge touches the support surfaces. Those two corners are going to be under a lot of stress. First of all, you have the tension from member 6 and then the forces trying to push outward from the big members coming down. So basically, pretty much all the force exerted on the bridge is going into those two corner joints. It makes me scared. Another thing that's scaring me is members 3 and 4; they just seem so likely to snap off where the load is being applied (the red box and arrow). Do you think they'll be ok without any other support from elsewhere? I don't really know a logical place to even support it. I suppose I could put something between members 1 and 3, but I'm really not sure if it's essential.
Anyway, just some of what I've been thinking about. Ben, if you could give me some feedback (unless, of course, you're too busy :D), that would be totally awesome.
Anyone else can comment too. :D Especially if you notice something I didn't!
Comments? Suggestions?
