Did anybody else laugh at the idea of using 2 grade 5 1" bolts per 2x4? I know wood is strong and all, but it's not that strong! They could have held it all together quite successfully with some 3" deck screws or 3/8" lag bolts.<p>By using such big bolts they actually made the structure less safe because they had to drill very large holes; those holes made the wood weaker than it otherwise would have been. I don't know who at MIT insisted that they use 1" bolts but that person had no business sticking their nose in.
The support structure may be overdesigned, but that's OK. What bothers me is how the cart attaches to the track. Here's a view of that:<p><a href="http://formlabs.com/en/company/blog/2014/08/27/from-3d-print-to-rideable-rollercoaster/" rel="nofollow">http://formlabs.com/en/company/blog/2014/08/27/from-3d-print...</a><p>The retention wheels are just riding on the underside of the plywood sheets. If they had a jam at a track joint, those might tear through the plywood or break off, allowing the car to derail and fall off the track. Unsupported plywood edges are weak and not good working surfaces.<p>Here's a standard roller coaster wheel assembly, with six wheels.<p><a href="http://www.themeparkreview.com/forum/files/dsc_0207_3.jpg" rel="nofollow">http://www.themeparkreview.com/forum/files/dsc_0207_3.jpg</a><p>Any 3 wheels can fail without serious trouble.
We are proud to say that Ben Katz, one of the leaders and designers of the project interned at Formlabs over the summer and used our printers to make a beautiful detailed model of the roller coaster.<p><a href="http://formlabs.com/en/company/blog/2014/08/15/formlabs-engineering-meet-ben-katz/" rel="nofollow">http://formlabs.com/en/company/blog/2014/08/15/formlabs-engi...</a>
I would have liked to see a loop combined with a gyroscopic chair, so no person is actually upside-down. It also seems like these are the sorts of things you are supposed to just build without university approval ala Real Genius.
"EHS said No Upside-Down People. Period."<p>Well, they didn't say anything about cows, did they?<p>Hey guys, you're MIT hackers. Involve a cow, will you? Upside-down, if at all possible...
This is pretty much the gold standard, built by ONE guy...<p><a href="https://www.youtube.com/watch?v=5gcoV3MkmY8" rel="nofollow">https://www.youtube.com/watch?v=5gcoV3MkmY8</a><p>Took a lot longer than a week, I'm sure, but it's an actual proper coaster. He later went on to work for one of the coaster companies for awhile IIRC.
While this is awesome work, I find it sad that those involved seem to have cheerfully acquiesced to the diktats of a safety- and image-obsessed administration.<p>Or perhaps their true attitude just wasn't appropriate for this blog post.