CC Express started, PDF posted

[caveduck]

/duck sneaks in for a hit-and-run post

Gonna finally do a little building this weekend - pulled out a CC express...scanned stuff, took parts photo, PDF posted to my small-but-slowly-growing hi-res plans archive at https://www.caveduck.com/rocketplans.

I tried to design a useful archival quality PDF instead of just slapping things into it. It has a decent stitch-up of the full kit card @300dpi, a "readme" info file, a photo of the parts laid out on a cutting board grid so you can see the tube lengths etc., instructions, a 1200dpi decal scan cleaned up and trimmed for making waterslides, the laser fin sheet and pic of enough of the parachute to show color and design. Hopefully enough to let future parts and packaging variants to be detected.

My younger daughter, who has real color sense and could maybe turn out to be a designer, looked at the color scheme and pronounced it a "rocketry fashion mistake". :no: Seems she agrees with me that the bumblebee-scheme decals don't go with the red/black paint. So it will get a non-standard paint scheme of some sort.

Just so this isn't a photo-less post here's the parts pic.


This may or may not become a build thread but I sort of doubt it.

 

[caveduck]

One-day assembly with CA and 5-minute epoxy and into the paint queue! A few minor mods:

• Added about 3' of kevlar shock line attached to front of the upper stage engine mount
• Changed lugs to 3/8" long pieces of 3/16" i.d. brass tube
• Moved rear centering ring of upper stage engine mount forward 3/4" to allow for a stage coupler
• Added snap swivel to clip the nose cone onto the rig. This lets you tie both the chute and the shock line to the strong metal loop and eliminates transmitting the chute opening force through the flimsy plastic loop on the nose cone.
• Moved rear lug forward 1/2" from back of main tube and front lug back about 1", mostly for aesthetics

I searched in vain for a BT-55 coupler but it can be added at any time later so it won't block the project. The nose cone had "ledges" at the mold lines and had to be wet-sanded quite a bit. Still ruminating on the paint scheme.

 

[Patriot]

Speaking of shock cord mounting . . . I have been using the ignitor sleeves that Quest uses for shipping . . . I tie the shock cord around 2 of them and then insert the pair into the nose cone along with the rest of the cord . . . makes a nice neat package with less chance of chute lines tangling plus it's easier for me to load. I'm new here so I'm sure some other guys are doing the same thing.

 

[caveduck]

Fin acreage CA coated (dang that took a bunch of glue), block sanded, spot putty filler applied to booster. I promise photos at the end...after all it's just a 4FNC with a booster.

 

[caveduck]

Maybe this will be a little bit of a build thread after all. After various iterations on finishing procedures I've used the CC as a guinea pig for a "1+1" prep with just one application of filler and one of primer. Previous tries have usually required more than one filler or primer step, but after sanding the primer out to a near-zero defect surface I think I've got it this time. Here's the recipe:

0) Shape the fillets carefully to avoid burbles and uneven spots that would need a lot of filler. One of the best things I know of here is to wave a heat gun (briefly!) at the epoxy to make it flow out a little.
1) Seal fins with thin CA. This time I used a pretty heavy coat - more than the minimum amount needed to touch all the wood.
2) Block sand the CA thoroughly. This starts to reduce the wood grain quite a bit. I sanded a lot more aggressively here than on previous models, and I think it's pretty important for preventing narrow but deep grain marks that are hard to fill.
3) Filler coat with spot putty diluted with lacquer thinner.
4) Block sand again, removing almost all the filler.
5) Heavy spray coat of Klass Kote white epoxy primer. For this one I sprayed a good layer, let it flash off for about 10 minutes, and then sprayed some more. A suction-feed detail gun at 35-40 psi made quick work of this.
6) Sand out with 220->400 grit. Block sand the flat parts of the fins; use small dowels for the fillets and around the lugs. Don't go beyond 400 grit. This primer is amazing stuff and even though it won't load your sandpaper at all, you can get it smooth enough to have adhesion issues with the top coat.

Still no photo, it's a featureless white ghost at this point. It's ready for color...my fashion adviser has suggested a powder blue.