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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.
Working on a side module to go with the bridge while I’m at it. The columns supporting the counterweight above were shifted out by a stud past the track baseplate to make it LGMS compliant (they want 16 studs clear instead of 14 for each track so basically no columns on the main 32×32 baseplate and no platforms higher than rail elevation). So designing a side module with a 1 stud cutout for the columns and provide a nice train shed and three gas silos. Going to articulate more details into the architecture of the model. The truck unloading dock has a little road. Let me know if that’s the right way to build the roads per the group MILS.
Fortunately, the columns are connected with technic back under the main baseplate with a little foundation system to make it all rigid. And reinforcing other areas of the design.
Phase 1 is nearing completion. I had enough of the Light Bluish Grey 9v track to use on the bridge section so it blends in with the other stuff. It only took two and an half hours to assemble this much. It’s a technic frame so everything is held together with beams and pins in a strong but light network.
Phase 2 and 3 will be the landings and Phase 4 will be the tower structure.
At 32 studs clear for the double track and 18 bricks high clear, this meets LGMS and will certainly have room for my trains and those of @emperorofthenorthpole. Even have an inner safety rail to keep wheels on track while crossing the bridge. Glenn, I figure your Nickle and Strasburg / PRR stuff will look great on a bridge that’s Pittsburgh Yellow. 🙂
Span is 40″ so four baseplates exact for anyone measuring track layout in Bluebrick. Landing 1 will be a single baseplate. Landing 2 w/tower will be a double baseplate (towards the center of the layout).
Update:
Phase 1 Bridge module is built.
Phase 2 Small Landing is built.
Phase 3 Large Landing. Currently gathering parts.The Phase 4 tower structure design has been pulled back by 8 studs to improve room for the bridge to theoretically swing up towards 90 degrees.
The motor features a 2 phase safety switch/liver to convert to manual mode. When in manual mode, the motor drive line is disengaged and the bridge can be raised by hand quickly.
The motor itself is connected to a PF toggle switch for control, not IR due to concerns of accidental operation by anyone trying to control a train on a channel.So it’s getting there.
Here’s another update.
I have the modules and sections built and assembled for a test. The mechanical principle works so now I have to sort out the required counterweight fill and then make any necessary adjustments to the motorization and other fine tuning. At the moment, it’s set to manual mode as previously mentioned. It’s big. It’s huge. It’s a behemoth.
@joshhall @rcgrier3406 @amplef0rth, @emperorofthenorthpole, are you excited to run your beautiful trains on it? 🙂 Definitely has that 1940s industrial feel to its aesthetic.That looks amazing. The fact that it is yellow is the chef’s kiss. If you wanted to hide the technic beam holes (to make it more sleek aesthetically), you could use technic pins https://www.bricklink.com/v2/catalog/catalogitem.page?P=89678#T=C to mount yellow tiles.
Thanks guys for the enthusiasm. In theory, it should meet or exceed LGMS standards for bridge weight support requirements. Seems pretty sturdy IRL as it’s a Technic frame. I’m currently having to modify the swing arm to better balance the loads at both positions so that the motor isn’t stressed out, but it’s getting there.
Here’s the updated framing for the Behemoth Bridge digital design, based on physical testing that identified the pivot points that worked in balancing the counterweight and the bridge load. Next phase is updating the upper tension arms between bridge and counterweight frame and then updating the motorization feature to have draw rods from the stationary frame to the bridge. Then it’s ordering the parts I don’t have (in pink). It may not be a perfect replica of a normal steel bascule bridge but this arrangement works in keeping the counterweight to a few pounds of ballast inside and avoiding extreme lateral stresses on the Lego plastic frame, compared to the conventional pin points being at the closest upper corner of the bridge frame. Plus, it makes use of most of the parts I already have. So it’s still on track for our March HG show.
This is looking great Michael!! Even without the mechanism working it would still be an impressive build!! Can’t wait to see it in action!!
I also agree that leaving the technic holes exposed gives it a more “industrial” look. Not quite “riveted” construction, but it has that “old school” look and feel!!
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