My King Dragon Star Explorer build

[Wally Ferrer]

King Dragon is making small carbon fiber rockets, so I thought I would build one. This is the Star Explorer, parts washed, then scuffed and scratched, i.e. prepped for epoxy. I used Rocketpoxy, with a few drops of black dye, an old screw eye out of my repair pile and the fin guide also from King Dragon. The tube is not standard, 22mm so my regular fin guides didn't fit. Carbon 1/4" launch lugs seem way too big for this model, even if going with composite motors. I started to use them, then pulled and cleaned it off- I will use a standard LL I think. I got a nice button as swag too..!

 

[Wally Ferrer]

The fit was too tight to get the Kevlar around the motor block and get it inserted into the motor tube. So I got creative...

 

[Wally Ferrer]

Here's the surface prep...

 

[Wally Ferrer]

Epoxy time, I started with the nose cone...

 

[Wally Ferrer]

Motor mount and fins...

 

[Wally Ferrer]

I'm debating the need for fillets, as the fins already sit in slots. I'll decide before I add the launch lug(s). I'd like to keep it carbon fiber, and over-sized lugs will still work on smaller rods. I also might go with mini or micro rail buttons...

 

[Wally Ferrer]

Attach the clothesline to the nosecone, and hang the laundry with a swivel. The Kevlar is nice and long, using a loose link(?) fold should allow a nice soft deployment...

 

[Wally Ferrer]

Close inspection of the fin joints made me decide to do fillets. I cleaned up some little bumps using some small files, taped to help keep things clean and poured on some Rocketpoxy, again with the black pigment. I decided to use the lugs that came with the kit. I used a section of 3/16" lug to keep them aligned, with some petroleum jelly to prevent epoxying it in accidentally.

 

[Wally Ferrer]

Time for some alcohol! ...for the fondant ball...

 

[John_lennon]

It's really cool looking I like the carbon fiber look. I'm new to this so please forgive the ignorance, but how do you do that to the string all the loops I'm talking about. Is this a normal thing to do? I'm guessing if it stays like that when the nosecone comes off from the charge that this design increases the tensile strength of the cordage.

 

[Wally Ferrer]

Thanks @John_lennon . The loops will pull out after ejection, but can add a little resistance slowing down full extension and provide some shock relief. If all the loops don't open, no harm, and no sudden jolts. Kevlar doesn't have any give, so when the cord is fully extended it just stops, if too short it can be a stress on the mount and nose cone. It also makes it easier to insert it into the small diameter body tube. The looping itself I have seen in videos, like this one from Badass Rocketry, now (Mach 1) the shock cord part begins at around 14:47 in...

 

[John_lennon]

Thanks for the info. Plus the build was cool to watch. I don't necessarily know how that type of looping is done with the shock cord. I'll check out apogee's website & youtube vids to see if there's a more detailed slower display of how the looping is done.