How to connect parts in a loop?

[THX1138]

I want to make some long arms for an asteroid redirection project. They will need to be made rigid. I connected parts in the VAB which looked like they might reinforce the arms but after loading on the launch pad, you see they're not actually connected.

Incidentally, are the I-Beams more rigid?

 

Edited July 2, 2016 by THX1138

[Majorjim!]

12 minutes ago, THX1138 said:

I want to make some long arms for an asteroid redirection project. They will need to be made rigid. I connected parts in the VAB which looked like they might reinforce the arms but after loading on the launch pad, you see they're not actually connected.

Incidentally, are the I-Beams more rigid?

 

Struts dude. Any part that is not connected add a strut from one side to the other.

[Jimbo Jangles]

1 minute ago, Majorjim said:

Struts dude.

'Nuff said. Only stock part that can do it during construction. I've seen people put docking ports real close together in the VAB and when the vessel loads the ports connect. I can't imagine docking ports holding together as good as struts though. 

[THX1138]

I tried using struts but I'd have to place them individually because mirror and radial placement produced undesirable results. They're really hard to place accurately as well.

[Jimbo Jangles]

Try the docking port trick.

[Majorjim!]

29 minutes ago, THX1138 said:

I tried using struts but I'd have to place them individually because mirror and radial placement produced undesirable results. They're really hard to place accurately as well.

Just take your time mate. One at a time is no biggie. 

[swjr-swis]

52 minutes ago, THX1138 said:

I tried using struts but I'd have to place them individually because mirror and radial placement produced undesirable results. They're really hard to place accurately as well.

You only really need to place the strut right once. Then make copies of the section with the placed strut and at placing them, the struts will connect the same way every time.

My suggestion though: make your frame from emptied SRBs instead. You will total much less parts, you'll need much less struts, and the frame will be a lot more rigid.