The Cosmic Cucumber - a Scratch-build Project

[wclune]

The only thing I would have done different was to laminate the fins.
Awesome Evan!

 

[EeebeeE]

Coming from you Bill, that is an excellent compliment. I am hoping that the fins will hold out. This will go into the transsonic space, but not necessarily punch through. I want to fly this often, including the URRF event and NYPower.

 

[EeebeeE]

Primer goes on the airframe. I found a great white primer at Home Depot that is designed to bond with plastic. Helps with the plastic nose cones. Lots of sanding got me to this point.



I am going to reach out to Stickershock 23 for some decals. If you can envision this being a neon lime green and the stars being opalescent, you can get an idea as to what it could look like.

 

[grady678]

HP ROCKETRY is alive....................nice work is an understatement!!!

 

[MasonH]

Love how this thing turned out!!

 

[GDJ]

This thing is gonna rip!

Nice and aerodynamic! Great job!

 

[awseiger]

I like how that tail cone looks!!! Sweet rocket

 

[EeebeeE]

Here is a little better iteration of the design.

 

[wclune]

This will go into the transsonic space, but not necessarily punch through.

It is not the ascent i would be worried about but the landing. pointy fins bust easy.

If you fly it at urrf I have a nice 38mm 10 grain motor. Not a fast propellant but longer burn. go HIGH!!:wink:

 

[EeebeeE]

It is probably going to land on the tailcone. I have an 18" drogue and a 54" main. I am using an Adept 22, so the main deploys at 600'. Landing speed should be about 16-18 ft./sec.

Haven't registered yet but I do want to fly at URRF. I simmed this with a J530 and it goes about 8,200-8,400' up. I have 21" of room for the motor. It will hold a 6xl case easily. If your 10-grain motor will fit, this thing could go way high.

I think I'll test fly it with an I-800 at the MARS May launches.

 

[troj]

Do you have more pictures of the process of forming and finishing the tailcone?

-Kevin

 

[EeebeeE]

Unfortunately no.

 

[EeebeeE]

Thought I would show you the electronics, although a number of components are recycled. I am using an Adept 22 altimeter for this rocket along with the bulkheads from another e-bay. But since I intend to fly the other rocket at a later date, I am using a different coupler tube to develop my av bay. I have found that 3 pieces of wood, 1/4" x 1/2 " x 6" adds structural integrity to the bay and is also sufficient to hold everything in place. It also minimizes the amount of ejection gases into the bay because I recess the bay into the coupler. One final benefit is that I can use threaded inserts (you can see them about halfway down on the wooden rods) to hold the bay to the forward airframe where the chute is mounted and blow the nose off to deploy the main.

The electronics board and I never got along because the epoxy always came loose from the tubes holding the e-board to the threaded rods. The solution for that is to cut small lengths of kevlar shock cord and imbed them into the epoxy. Since I started doing that, I have n longer had this problem.

 

[Machet_Man]

Another compliment on the work with the tailcone, thats a really hard thing to do and make look like one piece after cutting it into the triangular slits but you pulled it off great! I really wish I could pull off something that clean

 

[EeebeeE]

It takes a lot of patience...and a little cussing.

 

[EeebeeE]

Starting on the finish tonight. I had tried a Krylon flourescent green, but like their flourescent yellow, it is crappy paint. Doesn't cover and it spreads unevenly. Don't buy it. So I went with a John Deere tractor green which is an emerald shade. It will make a nice base coat, and then I will cover it with a clear glitter coat to give it a little personality and kind of an "Oz"-like appearance. After the glitter coat I have some real cool decals from Stickershock23 that are holographic silver and metalic purple that will go on it. Once those are on it gets a couple coats of clear gloss.

 

[qquake2k]

Looks good! I like that green.

 

[ckreef]

Looks good. I'm really interested to see how the glitter top coat comes out.

 

[Aksrockets]

Looks Great! Really nice job smoothing out that boat tail. It looks better then any commercially available one I've seen. Again, really nice work.

Thanks for sharing!

Alex

 

[EeebeeE]

Thanks. It took a lot of time. There are still some minor imperfections, but those should be able to be covered with glitter coat...or decals. God bless decals.

 

[EeebeeE]

Started applying the decals after the glitter coat. Then realized that the paint on the nose cone was not sticking. Crap. Oh well, I will repaint it. In the meantime, with the good side of the nose cone facing the camera. Here is how it looks so far. I was going for that "rocket-powered head shop poster" look.

Thanks to Mark at Stickershock23 for some amazing decals.

 

[MasonH]

Looks good! Kinda reminds me of a cucumber...

 

[grouch]

That does look tasty! You did a great job from start to finish. Can't wait to hear how it flies.

 

[ckreef]

Really nice.

 

[EeebeeE]

Here is a photo with all the decals on it. Final weight came in at 81.6 oz. Heavier than I wanted, but a J530 will still put it up to over 8,000'. This is probably one of the more unique rockets I have built. The biggest problem was with the paint. The last time I used a glitter coat, I got a very good paint from the local auto parts shop. They had discontinued it. So I bought Valspar from Lowes. Lousy glitter coat. Good thing I had lots of decals.

 

[qquake2k]

It turned out great!

 

[EeebeeE]

Took to the air yesterday. Flew great on a CTI I287 Smoky Sam. I had a P-nut recording altimeter keeping record. For some reason I lost power to my Adept 22 so the motor charge deployed the drogue and it landed without the main. Fortunately, no damage. Looking forward to putting it up higher over Memorial Day weekend.

 

[qquake2k]

Nice flight in spite of the electronics failure!

 

[Madison Alum]

Great build! Glad it came back undamaged.

 

[EeebeeE]

Our next flight is Memorial Day weekend. Going to put it up on at least a 5-grain J with a camera on board.