40d Talk:Bridge

Fluids vs bridges

Does a raised bridge prevent the flow of fluids? Guess I'll experiment and see if I can answer my own question. Yvain 21:21, 29 February 2008 (EST)

Yes. VengefulDonut 04:55, 1 March 2008 (EST)

picture: south-raising drawbridge

Here's a picture of a bridge that raises South, to clear up any confusion over which direction bridges raise. Basilisk 18:03, 27 March 2008 (EDT)

  Template:Qd

Items...

When a creature is crushed by a bridge, what happens to the items they had?--Lordmick134

When the bridge lowers, it completely ans permanently destroys anything it crashes on. So, there will be absolutely nothing under bridge, when it raises back.--Dorten 03:29, 4 April 2008 (EDT)

Not true! I had trapped a goblin inside a room with a bridge in it, and set the lever connected to the bridge to be repeatedly pulled. The goblin was stunned at most.--CrazyMcfobo 09:37, 16 April 2008 (EDT)

The goblin was likely flung from the bridge after stepping onto the extended bridge which then raised with the goblin still on it. Crushing is definitely an irrevocable and utter destruction. --JT 16:30, 20 April 2008 (EDT)

Channeling

Checked the channeling article, nothing there, either. I have a bridge that raises to the right to form a wall, part of my outer defensive perimeter. I was digging a channel around the fortification wall and wanted to channel under the bridge. I raised the bridge ... I cannot channel. It never creates the flashy 'this is gonna be channeled' designation anywhere where the bridge could lay over. I can channel any where else. I can also remove the bridge, channel what I want, and replace the bridge just fine. What gives? Is this a known bug? --Geofferic 02:35, 29 May 2008 (EDT)

As far as I know you can't dig on constructions. When the bridge is raised it is still considered to be constructed there. (or something like that) I had the same problem with some retracting bridges. To fix it I just removed the bridges and dug the channels, and then rebuilt them. --Lotus 10:13 (CST) June 11, 2008

This is particularly applicable to the process of obsidian mass production. If you have a bridge-held reservoir at Z-level 1, and a magma reservoir at Z-level 0, you will have to destroy and rebuild (and re-mechanize) your bridges every time you make obsidian. To solve this problem, I re-routed my magma to Z-level -1, and left Z-level 0 as empty space. I also re-routed my access paths so that miners will arrive in Z-level 0 from the west side, (and channel East to West, one row at a time) and my stone haulers will arrive in the northeast corner, so they can start hauling stone as soon as it is channeled out. Although this took several false starts, it is now a highly efficient system. If I ever do it again, however, I will build MUCH bigger reservoirs... And way wider channels for the magma. It takes FOREVER to fill my magma buffer... Would pumping the magma fix this? --wattj 17:26, 1 February 2009 (EST)

Probably. Pumped magma behaves differently, while the pump is on.--Zchris13 05:23, 24 May 2009 (UTC)

Bridges as a temporary wall

I want to build a wall by pulling a lever, to block off a tunnel three squares wide. It is a mine tunnel with no channel above it.

How long should the bridge be?

It looks like this:

▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ò▒▒▒ .........╥......... .........║......... .........╨......... ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒

GarrieIrons 05:12, 3 June 2008 (EDT)

Well, you have to be careful. Don't forget, by raising a bridge, you can potentially obliterate your dwarves in the process. So try not to make it too wide. --AlexFili 05:41, 3 June 2008 (EDT)

My question is, if I make it too long will it smash into the roof or anything?GarrieIrons 06:09, 3 June 2008 (EDT)

As far as I know of, it won't smash into the roof. The only concern is that if the bridge is too long, a dwarf may get accidently crushed. --AlexFili 06:14, 3 June 2008 (EDT)

Buildings that span multiple/variable z-levels are, at the current time, not possible. So, just build a 1x3 bridge, set it to raise west or east, and you have a wall! A toggleable wall! --Savok 09:09, 3 June 2008 (EDT)

I'd suggest doing a 2x bridge, as you'll have to track down the lever anytime you're curious as to whether the bridge is up or down, as a 1x or x1 bridge looks the same raised or lowered when raised on it's short axis. (e.g. the bridge above would look the same raised or lowered.) --Edward 09:59, 18 June 2008 (EDT)

Retractable/drawbridge

How can you specify which type of bridge you want to build? --AlexFili 05:45, 3 June 2008 (EDT)

When you go to place a bridge, by default it retracts. If you press wadxs you change the direction it raises: w = north, a= west, d=east, x=south, s=retracts. I don't know how to set the direction it retracts though.GarrieIrons 06:12, 3 June 2008 (EDT)

So if it retracts, it creates an impassable wall? -AlexFili 06:15, 3 June 2008 (EDT)

No, it disappears. If it raises, it creates an impassable wall, whose direction is the same as the raise direction. Try it out.

And, Garrie, it isn't possible to set retract direction since there is no such thing. --Savok 09:09, 3 June 2008 (EDT)

Well I guess it doesn't really matter which way it retracts... although if a bridge is built outward from a cliff running east-west out to the chasm which is to the north then obviously the bridge retracts back to the edge it is anchored at (it can hardly retract back into mid-air...).GarrieIrons 23:22, 6 June 2008 (EDT)

Oh, really? --Savok 23:32, 6 June 2008 (EDT)

well I guess applying common sense to DF might not be the best idea... but common sense would [bold]suggest [/bold] the bridge retracts back to where it was built from.GarrieIrons 00:03, 7 June 2008 (EDT)

We don't use BBcode here. I don't think that even is BBcode, but it is in that style. To make bold text, type '''bold text'''.

And you're right that applying common sense to DF doesn't work. Even the least of peasants can carry thousands of pounds pebbles in a backpack. --Savok 09:06, 7 June 2008 (EDT)

Actually, they carry thousand pound boulders in their hands. And cut it into blocks with their mind--Zchris13 05:24, 24 May 2009 (UTC)

Bridge-on-bridge action

I've just added a note about retractable bridges being able to be built using existing bridges as support. However I'm currently unable to test what happens when an intermediary bridge is retracted or raised (I have no stone for mechanisms!). I'm assuming that any bridges relying on the retracted/raised bridge for support will collapse, but it should be tested (and noted), if someone else has the time and inclination! Raumkraut 12:04, 14 June 2008 (EDT)

I can confirm that when the first bridge is retracted the second one deconstructs. And also if you choose to do your testing using extreme cliffs and "accidently" make 6 of your 7 dwarves stand on the second bridge then they will die a horrible death after falling 18 stories. --Makuus 16:54, 16 June 2008 (EDT)

What if you raise both of the bridges at the same time? --AlexFili 05:48, 17 June 2008 (EDT)

The same thing happens, the second bridge deconstructs again --Makuus 13:48, 22 June 2008 (EDT)

I attempted this quite some time ago, I think. I had something like ten bridges in a row built off a cliff, and retracted them all at once with one lever. All but the first one (which was connected to the cliff) shattered into stones instantly. --SL 10:29, 23 July 2008 (EDT)

lockdown system

in one of my old forts i had a setup so if the opponent got near my bridges a lever would be pulled and the opponents would fall into the lava with a godlike imp in it, it would use multiple bridges however and i would have to rebuild atleast 1, it was sort of like a tesselation of crosses

Flying Bridge

Build stairs up. Build stairs down atop it. Build a retracting bridge extending into open air from the downstairs. Link the retracting bridge to a lever. Pull the lever to retract the bridge. Deconstruct the down stairs. Deconstruct the up stairs. Pull the lever. Remove the lever. Bridge flies. Rkyeun 11:38, 18 July 2008 (EDT)

Shame this can't be used to build eg. twisty retractable catwalks due to the above confirmations in Bridge-on-bridge action. :/ --Heron 09:46, 23 July 2008 (EDT)

You could probably get something similar by just having occasional pillars sticking up, constructed by building towers of stairs, building a wall adjacent, then deconstructing the stairs. If you have each bridge anchored to one pillar, you ought to be able to get many retractable bridges in a sequence. --AlexChurchill 12:08, 23 July 2008 (EDT)

More testing. Retracted bridges never deconstruct. Make a chain as long as you like by keeping them all retracted until scaffolding is removed. Un-retracting bridges never deconstuct nor cause deconstruction. To make a path of multiple flying bridges build a scaffold for the first bridge, retract it, deconstruct the scaffold, build the second scaffold, retract that bridge, deconstruct that scaffold, and so forth. You can then unretract all bridges in any order and they'll all stay up. Retracting them again in any order caused them to fall. Rkyeun 09:00, 2 September 2008 (EDT)

Stockpiles under bridges

I tried to make a refuse stockpile with a drawbridge over top, and I couldn't place the stockpile where the bridge would lower onto. Can anyone else confirm this for the new version? Falcondude 11:05, 31 July 2008 (EDT)

Yeah, that won't work. If you are trying to make a garbage compactor, make a ledge and designate a garbage dump with (i) that will drop the items where the bridge will close.Trevlyn13

You don't need to make a ledge. Just retract the bridge (so you aren't dumping ontop of it) and make a garbage dump zone where the bridge will close. Voila --Sinergistic 01:03, 21 January 2009 (EST)

Drawbridge vs colossus

Yesterday a bronze colossus got trapped between my 2 moats, right under the drawbridge. It was too close to the catapults so that the operators wouldn't fire them, so I tried to crush it with the bridge. My bridge broke instead. (later I killed it by shooting hundreds of arrows) If anyone could replicate this, and also experiment with other megabeasts.... (actually I made this account to tell people about this) nautilusfossil

As far as I know, Dwarven Atom Crushers™ break on megabeasts and demons. Cage Traps are the way to go for megabeasts, but demons are immune against them.

I don't know about semi-megabeasts considering bridge-breaking. MC Dirty 18:17, 19 September 2008 (EDT)

Dwarves negative thoughts regarding crushed friends

Dwarves respond to friends or family members being crushed by a drawbridge as if they'd been killed & then not buried: "He was forced to endure the decay of a sibling lately. He lost a sibling to tragedy recently." (I'm certain this was due to the drawbridge, as all the siblings *except* the one that was crushed had these negative thoughts. Nobody else in the family had been killed by anything yet.) --Sev 14:49, 2 September 2008 (EDT)

Melty mechanisms... redux?

Curiosity kills my dwarves - I'm not wasting the time to do this myself. Will mechanisms melt out of bridges that are submerged in magma? --GreyMaria 22:31, 28 September 2008 (EDT)

I have no idea, this is a good question. While writing a reply of my thoughts I kept re-thinking some things. If Magma passes over the bridge I'm pretty certain that the mechanism will act like a flood gate's. It will not melt away as long as you don't raise the bridge. If you do raise the bridge, the mechanism will melt away and the bridge could do a number of things. Before I keep typing about what I think will/could happen, I'm just going to go ahead and pass on a wall of text. Dakira 1844, 28 September 2008 (PST)

But fluids cannot enter the tile of a raised bridge, whereas they can enter the tile of a lowered bridge. In this way, a raised bridge would be analogous to a _closed_ floodgate, and a lowered bridge to an _open_ one. Random832 21:51, 25 November 2008 (EST)

GO GO GADGET TEST MELTY MECHANISMS --GreyMaria 00:25, 16 January 2009 (EST)

Nope, doesn't work. The mechanisms melted... and just when I was making to re-pull the lever, too. D: --GreyMaria 01:05, 16 January 2009 (EST)

Bridges and wagons?

Is is possible for wagons to drive over bridges? I would assume so, but I don't want to get hasty. --w-dueck 23:50, 3 December 2008 (EST)

yes, anything can pass over them. Dangerous Beans 00:29, 4 December 2008 (EST)

Okay, thanks. Now that the mean kobolds can't escape when they steal my stuff, I am free to bludgeon them with random objects! --w-dueck 18:39, 4 December 2008 (EST)

You have to spot them first, though. Put war dogs on restraints in a recessed area that leads to the trade depot.--Maximus 22:08, 4 December 2008 (EST)

Indestructible Caravan

I needed to test out my whammer slammer bammer on something but no goblins volunteered for so long I was forced to attack the dwarven caravan instead. The mighty bridge swung down upon the lone wagon and was riven like a banana dipped in liquid nitrogen, leaving the wagon unscathed. If we could breed and train war wagons we'd rule the world. The 3-tile-wide parts of it anyway. --Corona688 18:55, 9 December 2008 (EST)

But a single cave swallowman can scuttle an entire wagon in two milliseconds. Maybe wagons count as a megabeast? --GreyMaria 23:00, 9 December 2008 (EST)

Funny. I dropped a bridge on a Mangrove Wagon yesterday, and the wagon vaporized like any other sap. It was an iron bridge - maybe that's the difference? --HMS Prancytime 16:15, 1 February 2009 (EST)

Megabeasts break bridges even without atomsmashing?

Situation: I captured a Titan and pitted it onto a drawbridge from a platform a Z-level above. The drawbridge is retractable and linked to a level. Logically, pulling the level will make the drawbridge retract and the Titan will plummet to his death.

But it didn't happen. The bridge refuses to budge. I haven't got a message about it whatsoever.

Is it possible for a Titan to break any drawbridge operation whatsoever no matter the end result?

--Shurikane 22:34, 6 January 2009 (EST)

Yes. A bridge is a non-construction building. Therefore entities with [BUILDINGDESTROYER] can nuke them. I doubt it. Did you find any mechanisms lying around, like next to the lever? --GreyMaria 00:02, 7 January 2009 (EST)

Nothing unusual to report. As far as I see, everything should be functioning normally. The Titan, by the way, does not move around. He stays right where I dropped him... --Shurikane 12:25, 7 January 2009 (EST)

Update: here's what I found out. A megabeast standing on a bridge will prevent said bridge from functioning. In my case, this means a retracting bridge will refuse to retreact unless the megabeast steps off or dies. --Shurikane 11:02, 10 January 2009 (EST)

A Zombie Elephant will do the same thing. --May Cause Drowsiness 07:29, 25 July 2009 (UTC)

Rain filling up ponds

Hi all. I just noticed something strange. I have a fortress without flowing water where it is hot (the ponds dry up) The evaporation depends on weather it is covered or not (I verified this 40d) But, if it is covered, then it doesn't refill with rain. So I thought, how about a retracting bridge. Nope. Even if it is retracted, the pond doesn't refill when it rains. Oh well. Probably has to do with the construction note above.Kwieland 23:16, 19 January 2009 (EST)

Try this: build a cavern under the pond, and a hatch cover linked to a lever between them. Wait until the pond fills with water, then pull the lever, and drain the pond. Close the hatch, then wait until it refills. Petersohn 17:40, 28 November 2009 (UTC)

Building at the end of a bridge

As an addition to the info regarding bridges constructed at the end of bridges, apparently you can build walls and floors at the end of bridges as well, but upon completion, they collapse, along with the dwarf who was building it. I only tested with a retracting bridge, but I see no reason the same wouldn't apply to drawbridges. Of course, this information isn't really useful, but a warning on the page would be nice. Actually, I suppose it would make an innovative way of killing off masons. --Mikaka 05:12, 23 April 2009 (UTC)

I just discovered this the hard way, when my mayor / broker / manager / legendary carpenter / only architect attempted to build a floor at the end of a bridge, only to plummet to his watery death in the ocean. Plans have been drawn to drain the ocean into the aquifer in retaliation. ~ Eidako 05:46, 27 June 2009 (UTC)

I can verify this affect: It has more to do with the bridge not counting as a solid construction and still allowing constructions next to it as if it would support them. Just make sure your walls are attached to other constructions that are somehow touching floors, and you'll be fine. I found this out the hard way, repeatedly, on my above-ground/wood-only fort while trying to use a bridge as temporary scaffolding in a water-duct drainage system that, sadly, did not work as water wouldn't fill upwards.

Magmapult.

If you have a bridge that raises directionally attached to a lever, and it has retaining walls, and everything is magma-proof, can you fill the retainer with magma, pull the switch... would it throw magma like it throws other objects? --Roflcopter! 22:35, 19 August 2009 (UTC)

An easy experiment to try - let us know how it works out.--Albedo 23:41, 19 August 2009 (UTC)

I tested with water, it does not get flung but it does get atom smashed. --winner 08:41, 26 September 2009 (PST)

Deconstruction Scaffold

Backstory: my new fort's entrance is accessible only via a bridge over the magma pipe, using two 3x10 raising bridges on the edges and a bunch of constructed floors in the middle (and constructed walls along the edges), and I recently decided to rebuild it with 3x2 raising bridges on the edges and retracting bridges in the middle (for dropping goblins into the magma, or for clearing away magma pumped onto the bridge). In order to do this, though, I would need to deconstruct the existing floors, removing the only path out of my fortress (except for the walled-off back door which I'd rather not reopen), so as a test, I attempted to build a retracting bridge over the floor and then remove the constructed floors underneath it. Amazingly, it worked, and it even left the building materials sitting directly on top of the bridge rather than falling into the magma pipe. --Quietust 14:00, 3 September 2009 (UTC)

Retracting ...bridgeapult?

So my fortress entrance is a bridge over a magma pipe (as described above for "deconstruction scaffold"). When I place items on the center retracting bridge and pull the lever to drop them, they fly into the air before falling down into the magma, some of them ending up on top of the retaining walls. I suspect that once I finish building a floor over the bridge (about 66% done right now), it'll start behaving properly and simply drop the items straight down into the magma. --Quietust 03:43, 5 September 2009 (UTC)

Bridgeapults forum thread

The bridgeapults has experiments to test what exactly bridges do --winner 08:35, 26 September 2009 (PST)

Automatic Butchering Experiment with Retractable Bridges

I performed repeated experiments using retractable bridges to let livestock fall to their deaths in 40d19. Using the step through method, I carefully observed the subjects while they were in the air. The apparatus used is a free standing tower with attach staircase and bridge.

top: |========|++x base: oox

Some general observations that might be helpful:

1. Creatures (muskox and cows) did not gain in maximum height. That is, they did not get tossed upwards (did not gain in z-level), but merely get tossed horizontally before falling down.

2. Creatures are tossed in a random horizontal direction (combinations side-to-side and front-to-back) by a maximum of 3 tiles before falling down.

3. Terminal height (100% kill rate over multiple mass tests) is 8F.

4. Care should be taken so that the creatures do not land on nearby auxiliary structures that may prevent fatal impact.

In other discussions, 100% lethalality distance to fall seems dependent on the size of the creature falling. --Albedo 21:22, 23 March 2010 (UTC)