faph

Exactly, it does. But the raised “island” between the rails solves it! Experiments signed off by Statler himself: No more design changes allowed ;)

This is what I've got now: Track now 1 plate lower compared with pivot point. I am also needing to curve and incline up to the bridge. This means at this end of the bridge I do need a raised area between the rails otherwise light train cars might derail at the half stud spacing between the track parts.

Extensive real-life testing over the weekend threw up an issue: When spacing tracks a stud apart, train wheels are prone to dropping on the inside of the split rail connections. This was even more of an issue when I was connecting the track with tiles-as-rails since that would have an additional half-stud gap. It doesn’t cause derailment but with the tiles-as-track it wouldn’t be a comfy ride for passengers either! So I’m going back to spacing official track a stud apart - the ride is just about smooth enough in that case. I will accept that I will be 2 studs out of grid :( And yes @Shiva I have now placed the pivot point a plate higher relative to the track and this does solve the collision issue nicely. Thanks for the tip!

This should be better:

@Phil B So yes you're absolutely right. A train plow does not have enough clearance for the studs! Thanks for keeping me right here.

@sporadic I see, the Lego logo on the studs is the problem. I’m happy to follow the “non-standard” technique in this case ;)

@sporadic thanks, I didn’t know that. Is there technically not enough space above the studs? It seems to fit quite nicely and Studio collision is also good with it. I could fix it easily but for cheapness I might just keep it as is. @Phil B I guess official Lego sets have enough clearance above the track? In the proof of concept I had a snot approach but in real life I like studs on top where possible. Our daughter needs to be able to place minifigs anywhere!

Plus we have the advantage of staff being able to get into the office in comfort! I guess if I worry about that level of detail I should move the door to the back of the building as well, so we can actually open the door fully. The track is actually intended to be slightly inclining/sloping at this point. Just haven't drawn it like that in Studio.

I am now going with this: it gets me back on grid and avoids the collision:

Proof of concept with 1/2 stud gap seems to work fine indeed:

Would this be the best way to use tiles-as-rail on the bridge: Or are there better ways to mount the tiles?

Thanks all. I should have said 9V plastic, as in battery! I meant with a classic rail I could easily align them in grid without a gap. Potentially I could experiment with tiles on the bridge itself to get myself back on grid. It feels ugly though… I think if the pivot point is any higher I might get into a collision situation at the other end as the bridge deck’s underside might be too much at an angle when it drops onto the pads. Not sure.

There are 2 slight issues with the design though. 1. I had to add an extra stud between the track segments at either end of the bridge. This would obviously cause the track to become "out of grid". 2. Even when spacing the tracks, there is probably 1 part of the bridge track that touches the fixed track. I think a knife might be required to address this :(. I am not sure if there are better ways to achieve this while making the track as smooth as possible. With the 12V rails that would be simple to achieve of course. But I do want this to connect to 9V track...

I have not seen too many railway bridges on this forum, let alone bridges that move! This MOC is not quite a common type of moveable railway bridge either, it's a double-leaf drawbridge. More common would be a bascule bridge. The difference being that a bascule bridge has it's contraweight either directly below the (rail)road or above it, but then directly attached to the bridge deck. The double-leaf drawbridge has a contraweight attached to a 2nd structure above the road. The nice thing about this bridge is that it allows me to keep the track very low to the ground. My Lego railway simply lies directly on our flooring. The contraweight includes a 2 x 6 x 2 weight brick. Not entirely sure how well the bridge is balanced - a real build would have to prove.

For avoidance of doubt, this shunter fits both a Powered Up Hub and a Powered Up medium motor.