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So apparently the group decided to retire the bridge by @joshhall during the Home and Garden show because of structural issues like sagging at the end points. I was highly impressed by the bridge frame as it did carry both my giant train consists at the same time. For fun, I’m tinkering on an idea for a new draw bridge in Studio and testing joinery and other techniques in case we should want another drawbridge.
Here’s some preliminary ideas as I work on the module in replication. It’s still a very rough draft and the counterweight tower is not yet modelled conceptually in studio but was drawn up on a sketch I have of the system and initial estimates of the weight requirements. This is a physics design exercise at this point with no guarantee of being built IRL in the short term given the size.
Basically designing this bridge around the show-stopping giant blue Schnabel car because if it’s big enough for that, it’ll be big enough for about anything, including my other cars and those of @emperorofthenorthpole without worrying about collisions with the bridge structure and damaging the beautiful trains everyone spend so much time building. Should be room for Glenn’s 3d printed running gear and the extreme dimensions of my Schnabel car.
And yes, the bridge is yellow. Because Pittsburgh. If I’m lucky, I can balance it out and have a PF motor raise and lower it, like the absolute boss that I am in engineering technic solutions.
ah, gotta be part of the LEGO RAIL facebook group.
[code]https://www.facebook.com/585488722/videos/443747504748685/?idorvanity=242867622834226[/code]
@joshhall, take a screen shot. I’m not a member of that group so I sadly can’t see the vid. 🙁
Now the bridge is taking shape with sloped ends. XD
The counter weight and tower frame is gonna be massive to balance it.
Yeah, yours was better than that, though I’m impressed at the triple track. They’re using that one truss piece that came out like a decade ago in a truck hauling bridge parts set. The truss part came only in that set and it’s be snapped up by the bridge builders for trains and cars like crazy as it’s rigid and doesn’t require calculating angles to align parts. Yours was all entirely Technic beams/liftarm parts put together in a logical manner. If possible, I’d like to see your bridge kept as a design study and as possible use maybe on a high elevation track as I’ve seen some layouts have tracks on different levels with mountains/hills.
Currently worked out some curve sloped interlocking end caps on the yellow drawbridge that will align the bridge with the farside landing when it lowers. So we won’t have to worry about the modified track end alignment for keeping wheels on the rail or power transmitting when the outer loops are someday electrified. 😉
Got a start on the articulated counter weight. Have to design the frame better but it’s a start to work with in Studio.
Thanks. Here’s the completed go at the initial design, complete with a mechanical room (with PF battery box, motor, and switch inside). Ideally, there’ll be enough ballast in the counterweight that it’ll only need a single motor to effortlessly move the bridge up and down.
My Schnabel car clears it at all relevant checks so @emperorofthenorthpole trains and my trains on the outer loops can safely navigate the bridge with no fear of collisions with any of the structural members.
Without ballast, it’s about 3900 parts, which isn’t bad. Just big yellow technic parts and some 9v dark bluish gray track which will have to be filed at the ends for the bridge to work and still carry the electric current.
I plan on publicly posting this on my PTW page on Monday (April Fool’s Day) as another of my absurdly large builds. Joke’s on the them as I will continue to develop the design and refine details for future use. 🙂
@playingwithechoes Is the plan for this to be something you build and own or for the LUG to build? If the plan is for the LUG to finance and build it, could it be a good candidate to include in project support?
I haven’t thought that far. It still needs a couple rounds of revisions on the details before I would look into building it. Other than a couple tons of 1×1 plates to fill the counterweight, it’s an otherwise relatively small project in terms of parts. Just mostly large parts and technic connector pins. It’s not anything super fantastic like a 50k parts life size sculpture of a famous person or anything like that which would warrant project support.
It might be able to test at least the connectivity of parts. Though, it’s all heavily reinforced technic frames so it’s not so much the bridge frame I’d be concerned about.
I have a knack for designing rigid frames and designing modules. The bridge part is a hefty six pounds of technic and reinforcements. The sheer depth of the upper and lower frames should prevent significant deflection and the inherent load limits should far exceed whatever Glenn or I roll on the outer loops. If built IRL, I have my means to physically test the load bearing capacity prior to use at train shows.
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