Radial Separators in stock

[Sharpy]

If you want to separate two vessels cleanly, without leaving any struts (including the Cubic, Octagonal Strut, which is a trivial solution... except it stays after separation), nodes etc, and you don't have a free node to attach a stack separator, here's how to construct a functional Radial Separator. It acts quite a bit like Radial Decoupler - except it detaches on both sides, staying as a space junk instead of sticking to either or both vessels.

Disadvantages:

- it's significantly thicker than the Radial Decoupler. About as big as the TT-70, the radial decoupler on long extensions.

- It appears as two decouplers in the staging sequence. Either of them detaches one end.

- It can't be saved as a subassembly to be brought readily. It must be constructed each time from scratch. (although using symmetry is perfectly possible, and copying it, etc).

- Parts utilizing it may be saved as subassemblies, but it can't be the root part (the part you attach the subassembly by). This obstacle is circumvented through a trivial trick though.

Part list:

- Structural Pylon 2 pcs.

- Cubic Octagonal Strut 1pc.

- Some dummy parts to attach these to. These will be deleted later.

- whatever you want attached - a probe, a missile, a second craft. Must be "visible", not "ghosted" so if it's a subassembly, attach it to any dummy part.

Let's start with the part you want cleanly separated. I've made a "lite" version of my SavingKlaw for deorbiting parts and kerbals from LKO. It's a little too thick for MK2 bay, and needs to be brought to orbit in bulk. I want it attachable under wings of an SSTO plane.

We need a little bit of empty surface so I detached one of the parachutes. Attach one Structural Pylon there.

Now attach a cubic octagonal strut to the pylon, and rotate it inwards. (W, W)

Attach an arbitrary dummy part to the strut. Note its node points inwards. (don't attach it to the outer node. Chances are better than high that you'll attach it to the Pylon instead, and the whole thing won't work.) Use "Mod key" to make sure it snaps to a node and not the pylon surface.

Select "Root", then click the cubic octagonal strut, then click the dummy part.

Open "Advanced" (the <|||| arrow in upper left corner), "Subassemblies". Click the octagonal strut and drag the whole craft except the dummy "root" to the Subassembly drop zone. Save. I always save these as "Unnamed" as it's only temporary.

Now you can either load (or build) the main craft) or go the "radially attachable subassembly" route. Let's pick the first one first.

Load your craft and attach structural pylons where you want the payload.

Load the subassembly "Unnamed" and attach it to these pylons. There. Don't forget to set the staging sequence!

Now a slightly more elegant path of turning these temporary subassemblies into proper ones... well, almost.

Instead of loading/creating a new craft, click "New" and build something like this:

The fuselage is the root part. It can be anything, any dummy part to stick the little strut on. Now load the subassembly and attach it.

Grab the whole thing by the one strut attached to the root part and save as a proper subassembly.

Now... what with the strut? Will it not remain attached to whatever we want this attached to? Nope. The aforementioned trivial trick is to load the subassembly, attach it anywhere, detach the pylon from the strut, attach it where it should go, then delete the strut. If you save with the pylon as a root part, it will insist on attaching by the narrower end, which doesn't decouple. By loading it with extra root part which you remove later, you can attach the active surface of the pylon to anything.

And how do they work?

Well, they work fine.

PROTIP: By abuse of the Offset tool for clipping you can make these far more compact by moving them closer together... even to a negative values