Fuel Pipe cannot attach to the second part...

[Jestersage]

I was trying to update an existing a rocket with n asparagus stage, and decide to go with good old fashioned fuel pipes. What I found weird is that in the existing craft, I cannot attach a fuel pipe going from the outside tank to the inside tank. This forces me to make a replication of the stage as a seperate craft (in which case I can attach the fuel line from outer tanks to the center tank) and merge it to the old craft.

Does anyone know what settings etc may cause it?

[bewing]

It's usually more that you have to have a clear path between the two endpoints. If the fuel pipe intersects any other part, then you are not allowed to place it there. By moving the camera around carefully, you can usually find a way to make it work.

[Jestersage]

However, it does not intersect other parts. In fact, it doesn't even attach to any parts (except the originating part)

Okay, I don't know WHAT actually cause it, but I found that it could be due to merging a craft A to craft b before I set up the change; when I go the other way (craft b to craft a), fuel line works fine.

Edited August 8, 2020 by Jestersage