Last time, I was contemplating how to add feedhorns to my High Gain Antennae from The Aerospace Place. The solution I eventually came up with was to use some 0.25mm fibreoptic strands, and to melt the ends into a blob by holding them close to a hot soldering iron. Sprayed white, these gave me something like the appearance I wanted.
Meanwhile, I’d begun to suspect that my Aerospace Place HGA was mounted on too long a supporting rod. To check, I scanned the relevant section of David Weeks’s drawings, halved the scale, and printed it out. Sure enough, the rod was too long, by about 5mm:
If you peer, you’ll also be able to discern my little feedhorns. Which are, if you compare them to the drawings. Mounted on the wrong dish ribs. Sigh. I’ll pop them off, repair the damage with new white decal strips, and then attach them where they should have been in the first place. And I’ll snip a bit of length off the HGA arm.
Then my revised umbilical fairing from The Aerospace Place arrived, and it was the right size:
There’s a roughened area on the “underside” of the CSM, evidently intended as a marker for where the fairing should sit. You can see it here, on a photograph taken a little earlier in the build:
The Z-plane of the CSM runs more or less through the vertical row of embossed circular features on the Command Module, to the right of the RCS thrusters, and the umbilical fairing is offset a couple of degrees from that line, so that all looks fine. If you’re not paying attention.
I actually had the fairing glued in place before I realized that it was offset in the wrong direction.
Aaargh. The fairing should actually be offset clockwise (as you look from the nose). It should be sitting more or less hard against the little radiator panel to the left.
Popping it off to resite it of course damaged my fragile Xtreme Metal paint, and I needed to do a bit of sanding to abolish the misleading rough area:
So now there’s a problem. You’ll see I’ve already applied some decals to the Command Module—a set of labels from Space Model Systems. I didn’t want to disrupt those, so I was faced with trying to mask off and patch the delicate chrome finish.
It went OK, I felt, though not perfectly, and I got the umbilical fairing in the right place:
Here’s a photo of the real thing, for comparison:
So a sensible person would have accepted this as a half-way decent save, and moved on. Instead, I decided I’d try to rectify a little flaw on the surface of the CM—a blob of glue that had extruded from the edge of the photoetch optics penetration. So I sanded the area down and set about doing another patching job. But this time, my masking didn’t work—it peeled off the chrome paint underneath it when removed. Another attempt to patch the problem, and I had more paint peeled off.
So I admitted defeat. And this is what defeat looks like:
I popped off all the 3D printed detail, and stripped the thing back to the bare resin using Xtreme Metal thinners, sacrificing my decals (and ordering a replacement set).
At which point I decided I might as well do the little job that I’d previously shirked—building up the region behind the rear radiators, which I did with some styrene strip and thin styrene sheet.
Then I went through the whole build again. The rear extension turned out fairly well:
This time I let my Xtreme Metal Black Base coat sit for three or four days before applying the Chrome, and suddenly it was adherent enough to be polished as advertised! Which meant I wasn’t going to need to apply a sealant coat, and could preserve my nice specular finish:
Which also meant that I could do some decent masking without damaging the paintwork, this time, so that I could paint on the red-brown finish around the CM thrusters. This would be more satisfactory than my own printed decals, which (you may recall) turned out to be a deep translucent red once in contact with the reflective surface of the Command Module.
So I used a set of appropriately sized hole punches—a 2mm round punch, and a 2x3mm oval punch, to make holes in my masking material. Still leery of using Tamiya tape, I opted for Bare-Metal Foil again, this time using gold to contrast with the chrome paint. Here’s the first set of roll thrusters masked off:
And it was at this point that things really hit the fan. More next time.