Problem w/ placing external fuel duct

[maddog59]

I've been playing for just about a year now, and have been successful building asparagus staging ... up until now. I've suddenly begun to have a lot of trouble getting the  external fuel duct placed properly between tanks. More often than not, no matter how long or short the duct runs, no matter how carefully I place so that there's nothing between points A and B, when I try place the second point, the duct disappears and just jumps to the new point, as though I'm  placing the first point. It's totally random when the bug will hit; restarting the game or rebooting doesn't change the behavior. Sometimes it works fine when I'm building a new vehicle, other times it fails. Sometimes it works fine if I'm working on a sub-assembly, other times it's fine. 

I'm completely stumped, and more than a little frustrated. It's enough to make me quit altogether at this point, so if anyone has ANY suggestions whatsoever, I'd be happy to take them on-board.

[Guest]

This happens with struts sometimes as well. I don’t know what causes it exactly but it’s basically not seeing the attaching surface as viable for attaching and sending you back to the first connection. As you say there is sometimes no obvious reason (therefore a bug I think).

The only workarounds I’ve found are (a) keep persevering by changing connection point (b) use EditorExtensions (this works for struts not sure about fuel lines) as you set the strut to somewhere it connects, then mouse over and press U and it neatens them up and puts to shortest path. Again not sure if it works for fuel lines though.

PS is asparagus staging still a thing? I didn’t think you needed it anymore as you can manually stop/transfer fuel?

[Curveball Anders]

1 hour ago, FruitGoose said:

 is asparagus staging still a thing? I didn’t think you needed it anymore as you can manually stop/transfer fuel?

Asparagus is still a good thing, but you don't need external fuel pipes any more.

Fuel cross feed in decouplers and fuel priorities does the job.

[maddog59]

2 hours ago, Curveball Anders said:

Asparagus is still a good thing, but you don't need external fuel pipes any more.

Fuel cross feed in decouplers and fuel priorities does the job.

What are these wonderous fuel cross feeds and priorities of which you speak? I've seen them in the action windows but never knew how to use them. If they would allow me to stop using the external fuel ducts I would become a happier rocketeer. Can you point me to a resource where I can learn more about how to set them up?   

[Curveball Anders]

2 minutes ago, maddog59 said:

What are these wonderous fuel cross feeds and priorities of which you speak? I've seen them in the action windows but never knew how to use them. If they would allow me to stop using the external fuel ducts I would become a happier rocketeer. Can you point me to a resource where I can learn more about how to set them up?   

You need to enable 'advanced tweakables' in the settings, then both cross feeds and fuel prios should show up in the properities pane.

[maddog59]

4 hours ago, FruitGoose said:

The only workarounds I’ve found are (a) keep persevering by changing connection point (b) use EditorExtensions (this works for struts not sure about fuel lines) as you set the strut to somewhere it connects, then mouse over and press U and it neatens them up and puts to shortest path. Again not sure if it works for fuel lines though.

Good to know this isn't a personal problem, anyhow.
I'd like to give Editor Extensions a try, but the only version I found on CurseForge was from 2015, for KSP 1.03; you've found it works as on 1.11.2?

1 minute ago, Curveball Anders said:

You need to enable 'advanced tweakables' in the settings, then both cross feeds and fuel prios should show up in the properities pane.

Yes, I have that enabled and see them in the properties, and I've seen the diagram appear showing the fuel flow, and I'm sorry I'm being dense, but I don't know how I'd manipulate the priorities to set one set of boosters to feed another set, as in an asparagus staging scheme. 

[Curveball Anders]

4 minutes ago, maddog59 said:

Good to know this isn't a personal problem, anyhow.
I'd like to give Editor Extensions a try, but the only version I found on CurseForge was from 2015, for KSP 1.03; you've found it works as on 1.11.2?

Btw, found this thread, where we speak more about asparaguses-ish

 

Edited May 7, 2021 by Curveball Anders

[maddog59]

5 minutes ago, Curveball Anders said:

Btw, found this thread, where we speak more about asparaguses-ish

That looks like a great resource thread... thank you! I think I now have enough knowledge to go and try blowing up more things again without the fuel lines. 

[Guest]

1 hour ago, maddog59 said:

Good to know this isn't a personal problem, anyhow.
I'd like to give Editor Extensions a try, but the only version I found on CurseForge was from 2015, for KSP 1.03; you've found it works as on 1.11.2

Try this one :

 

Says 1.9 but works ok. As it’s a LGG mod now, check you have dependencies installed too.

[linuxgurugamer]

1 hour ago, maddog59 said:

Good to know this isn't a personal problem, anyhow.
I'd like to give Editor Extensions a try, but the only version I found on CurseForge was from 2015, for KSP 1.03; you've found it works as on 1.11.2?

Dont' use Curseforge.  Use Spacedock, and as @FruitGoosesaid, make sure you have all the dependencies.

Better yet, use CKAN to install

 

[maddog59]

1 hour ago, linuxgurugamer said:

Dont' use Curseforge.  Use Spacedock, and as @FruitGoosesaid, make sure you have all the dependencies.

Better yet, use CKAN to install

Just curious, why the preference for one over the other? Most of the mods I've installed have come from Curseforge, and I've not had any trouble w/ them. 

[linuxgurugamer]

12 minutes ago, maddog59 said:

Just curious, why the preference for one over the other? Most of the mods I've installed have come from Curseforge, and I've not had any trouble w/ them. 

Most modders don't bother to update Curseforge as quickly as Spacedock and/or Github.  Not all, but most.  And, an FYI, I don't, at all, even though there are a few of mine up there.

[maddog59]

4 hours ago, Curveball Anders said:

You need to enable 'advanced tweakables' in the settings, then both cross feeds and fuel priority should show up in the properties pane.

So gave that a try, since I just can't get the external fuel ducts to attach at all, much less properly. I set the priorities for the two sets of boosters at 50 and 40, with the decouplers staged in the correct order, and the central stage as priority 20. I checked the fuel flow diagram and everything looked right. 2 sets of 2 boosters plus the central stage - 5 engines. When I launched, the first set of booster tanks drained completely, but kept running even though they were dry, and MJ2 didn't decouple them. Then the second set went dry, and didn't decouple, and all five engines kept firing, now off of the central stage. Is that what's supposed to happen? I was expecting each set of boosters to drop as they went dry, as happens when using the external fuel ducts. But if the engines are continuing to push, I suppose that's good ... yes?

[Curveball Anders]

18 minutes ago, maddog59 said:

So gave that a try, since I just can't get the external fuel ducts to attach at all, much less properly. I set the priorities for the two sets of boosters at 50 and 40, with the decouplers staged in the correct order, and the central stage as priority 20. I checked the fuel flow diagram and everything looked right. 2 sets of 2 boosters plus the central stage - 5 engines. When I launched, the first set of booster tanks drained completely, but kept running even though they were dry, and MJ2 didn't decouple them. Then the second set went dry, and didn't decouple, and all five engines kept firing, now off of the central stage. Is that what's supposed to happen? I was expecting each set of boosters to drop as they went dry, as happens when using the external fuel ducts. But if the engines are continuing to push, I suppose that's good ... yes?

pic of that ship?

First, drop the external fuel ducts, they are useless.
Second, what kind of boosters? SRB are out (unless you go for my fancy hybrid setup).

 

[maddog59]

3 minutes ago, Curveball Anders said:

First, drop the external fuel ducts, they are useless.
Second, what kind of boosters? SRB are out (unless you go for my fancy hybrid setup).

 

No external fuel ducts; and the boosters are all LFO, just like the central stage: I hope these show you what you need: 

[Curveball Anders]

A bit hard to tell from the pics but simply.

Core with fuel priority at 0 (of more than one tank, lower higher up)

Decoupler with cross feed on.

Booster tanks with fuel priority higher than any in the core (again lower higher up in the stack but lower than core).

Staging set to fire both main and boosters, and then to stage the decouplers (when the boosters are empty, or automagic if using MJ).

That way the engines will drain from the bottom booster tanks and up, and when the all booster tanks are empty, stage 'em.

 

 

Edited May 7, 2021 by Curveball Anders

[maddog59]

46 minutes ago, Curveball Anders said:

A bit hard to tell from the pics but simply.

Core with fuel priority at 0 (of more than one tank, lower higher up)

Decoupler with cross feed on.

Booster tanks with fuel priority higher than any in the core (again lower higher up in the stack but lower than core).

Staging set to fire both main and boosters, and then to stage the decouplers (when the boosters are empty, or automagic if using MJ).

That way the engines will drain from the bottom booster tanks and up, and when the all booster tanks are empty, stage 'em.

I think I understand and will give it a try, but a couple of questions to clarify, if I may:

The core and each booster consists of 4 tanks; are you saying that each tank should each have their own priority? Or can all of the tanks in a unit (core or booster) be at the same priority? For example, the four core tanks, from the bottom up, should be something like 0, 1, 2, 3, with the 4 booster tanks for one pair set to 10, 11, 12, 13, and the last pair (first to be jettisoned) would be 20, 21, 22, 23? Or, could the core tanks all be set to 0; the first booster pair set to 10, and the second booster pair be set to 20?  

As for the decoupling, that was what was puzzling me: I'm using MJ2, and normally when the tanks run dry the boosters are jettisoned. But this time, the booster tanks were dry, but the engines were still firing, and MJ2 didn't jettison them. I had to manually stage each set once I saw that the tanks were dry for a given pair of boosters.