Problem Attaching Subparts in VAB or SPH Build Editors

[JStevenson]

 I spent a very frustrating 1-2 hours last night struggling with the building editor and realize perhaps I need some help!

I'm running the most recent KSP version, in Career mode.

I've experienced the problems I had last night on and off these past months but last night was the real kicker.

I'm trying  to assemble a Rover payload to send to Duna. I'm more or less folllowing one of the Modular Base Building tutorials like on YouTube.   I gave up try to use the "bottom carrier" style of.rover since I experienced very strange (and violent! ) problems involving try to position the rover underneath a Base tube payload. Maybe this worked OK on previous KSP version but on the latest version I would experience explosive part collision effects where the tube would blow up into the air, the moment when the rover was underneath the power dock port.

So - I switched to another method involving a pair of small 4-wheel rovers which can dock to the sides of components (using Dock Jrs) and carry parts around with legs up. These rovers are used in pairs.   They also click together using their back dock ports to form a larger 8 wheel rover. Which I've found can move just about anything! 

Anyways, I am finding it impossible to connect these two rovers together in the VAB or SPA build editors. The editor does not always seem to recognise the docking JR points as valid attachment points.   I was able to attach Rover1 to a small Base node part (basically an OCT2 with Docking Jr's at both top and bottom ends). But attempts to load/merge Rover 2 and have it attach to the other side of the Base Node all fail. 

The strange thing is in the tutorial videos this all seems fairly easy and trivial. Has something changed since 2014 so that Dock ports are problematic attachment points in the build editor. Or is their some other technique or editor command I'm not using correctly here. 

I'll try to supply screen shots when I'm back on my Home PC (typing this now on my cellphone)

Cheers, 

J Stevenson

"Get your Ass to Dooon-ah". - Arnold Kerbin.

[ThreePounds]

This is a fairly long post and I have trouble understanding what exactly your issue is? I suspect it's the sub assemblies not attaching correctly? For some strange reason there are two methods in KSP to get to vessels to stick together: Merge and sub assemblies. Both function somewhat differently and have their own quirks and are confusing to use at the beginning. Here is how they work:

Merge: You can only merge and attach a vessel correctly if the root part can be attached. From my experience it's best to have an open node on the part you want the other vessel to attach. Make that your root part. Load the second vessel, then merge the first and attach it. I currently can't remember if you can surface attach merge too, I have to try that out.

Sub assembly: The quirk of this method is that you can't save the root part as part of the sub assembly. So if you want to save an entire vessel, you have to attach a dummy part to the node you want the attachment to happen, make that the root part and then save the rest. You can then load your second vessel and attach the sub assembly.

Like I said, this feature of KSP is quite confusing to use. So if you're still having trouble, you can share the craft file with me and I make some screen shots or a short video for you showing you what I did.

[JStevenson]

Thanks for your advice.  I actually do have a screenshot but haven't figured out how to attach it to a post here!   Anyways, the basic problem is I can't get my two rovers to "stick together" via their attachment nodes (all are Docking Port Jrs).  Even though this works fine in live running tests.  I'm simply trying to figure out a safe way to package two of these bad boys in a single payload to send to Duna.

[HvP]

3 hours ago, JStevenson said:

the basic problem is I can't get my two rovers to "stick together" via their attachment nodes (all are Docking Port Jrs).  Even though this works fine in live running tests.  I'm simply trying to figure out a safe way to package two of these bad boys in a single payload to send to Duna.

When you load a sub-assembly it will only attach using the part that was designated its root part. If you want to save the rover as a sub-assembly that will attach using the Docking Port Jr. then you need to use the "Re-Root" tool to designate the Docking Port Jr. as the root part before you save it as a sub-assembly.

Using the "Re-Root" tool is a little tricky. It's the zig-zag line icon to the right of the "Rotate" gizmo at the top of the editor. Once you select the "Re-Root" tool you will need to click once on your rover model, then click on the part of that model that you want to become the new root part - your docking port in this case. The rover should reorient itself to show that it now has a new root orientation. Then, open your sub-assembly pane, click on the new root part (the docking port) and move your rover over to the sub-assembly drop zone and save it.

After that, when you select the rover from the sub-assembly list it will attach using the docking port to any available end-node on the ships you are editing. For future reference, there are several parts that  cannot be used as root parts. Radial decouplers are the most frustrating, they can't be used as a root part, but in-line decouplers can be. Any item that can't be the first part used to start construction also won't work; like parachutes and ladders.

Edited September 8, 2017 by HvP

[Palaceviking]

Re-root. ^^^^^ !