Problem matching VAB and Orbit assembly

[Up The Ying Yang]

HI. I am trying to assemble an orbital fuel station. I'm using a spoke and wheel style. One six point hub with six arms. I have hub adapters on each arm with a long structure linking the arms.

The problem I have run into is I've assembled the parts in the VAB and they all fit perfectly. But in orbit there is a huge gap between one hub cap and the connecting structure.

Am I missing something obvious? Why would there be such an obvious gap when in the VAB they all fit?

EDIT: Oh yes I'm using KSP 1.0.5 on a windows pc

Edited April 15, 2016 by Up The Ying Yang
Info

[FullMetalMachinist]

1 hour ago, Up The Ying Yang said:

Am I missing something obvious? Why would there be such an obvious gap when in the VAB they all fit?

What you're missing is that the actual craft structure in the game is a "tree" where each part (except the first one, or "root") can have only one parent part, and as many children parts as you want. See this for more info. 

So in your example, the center is the root, and each arm is a child of that root. Then when you start building out the circle, the arms are the parent for the radial sections. The problem is when you try to get two radial sections to connect. If you have section A on the station and are trying to place section B, section B will only attach to one place, either the arm from the center or to section A, but not both because that would give to two parent parts, and that's not allowed. 

The reason it looks right in the VAB is because there are no physics forces acting on it in there, but as soon as physics start it deforms. 

One solution is to stitch it together with strut connectors (struts, fuel lines, and docking ports are special exceptions to the "no two parents" rule). Another thing is at the spot where you're trying to "close the circle" you can put a docking port on each loose end. They won't actually be docked in the VAB but when physics starts they should dock right away. 

If you have any other questions or problems with what you're trying to do, a screenshot or two goes a long way toward getting specific and reliable help. 

[Up The Ying Yang]

56 minutes ago, FullMetalMachinist said:

What you're missing is that the actual craft structure in the game is a "tree" where each part (except the first one, or "root") can have only one parent part, and as many children parts as you want. See this for more info. 

So in your example, the center is the root, and each arm is a child of that root. Then when you start building out the circle, the arms are the parent for the radial sections. The problem is when you try to get two radial sections to connect. If you have section A on the station and are trying to place section B, section B will only attach to one place, either the arm from the center or to section A, but not both because that would give to two parent parts, and that's not allowed. 

The reason it looks right in the VAB is because there are no physics forces acting on it in there, but as soon as physics start it deforms. 

One solution is to stitch it together with strut connectors (struts, fuel lines, and docking ports are special exceptions to the "no two parents" rule). Another thing is at the spot where you're trying to "close the circle" you can put a docking port on each loose end. They won't actually be docked in the VAB but when physics starts they should dock right away. 

If you have any other questions or problems with what you're trying to do, a screenshot or two goes a long way toward getting specific and reliable help. 

OK, I see what you mean. That helped tremendously. Thanks!