Until the weather turned ugly I was planning on flying a rocket big enough to get level 1 and level 2 TRA certification this weekend. While it looks like I will have to hold off until next month, I can at least share a short build log.
The rocket is a kit from Giant-leap rocketry. It comes with a nose cone, body tube, motor retainer and centering rings, and fins all cut out and ready to assemble. It also comes with a parachute and shock cord, Kevlar wadding, and launch lugs. In other words it comes with everything except fuel, epoxy, and patience.
Unfortunately, for reasons that are too complicated to explain here, I was not able to take photographs of the first few steps. So I pick up after having put the motor retainer and centering rings in the base of the tube and tacking the fins in with a little bit of epoxy. The next step is to really glue the fins in. And I mean really glue them in.
This involves adding thick epoxy fillets to each fin interface. The outside is actually the least important in terms of strength, but a sharp transition is bad for aerodynamics. So I added a fillet made of epoxy mixed with millions of micro-balloons—microscopic, vacuum-filled plastic spheres. This keeps the mixture light, but add lots of volume.
The next step is to put the final centering ring in the base. I used JB weld instead of standard epoxy because this part can get very hot from rocket exhaust. Most epoxies are destroyed by heat, so be sure to use something heat tolerant.
After that construction is pretty much complete. All that's left to do is paint. I started with a couple of coats of primer followed by three coats of flat white.
Then I did some personalizing. I channeled a Mercury Redstone and added some test pattern checkerboards in black. I also painted the nose cone black at this point.
All that was left was to add the launch lugs and add some stickers.
When I go to launch I'll slide the motor in and stuff the parachute and wadding in the top. Then hopefully it'll fly straight up 3,000 feet! I will follow up with a post with pictures, and possibly even a video of the launch—which at the moment looks like will happen the last weekend in June.










2 Comments
Hopefully your L1 cert went well. That paint job is KILLER, I love it! I certified L1 on a Liberty 4 as well, great kit (shameless plug: http://mikecronin.name/2009/10/success-my-l1-certification/).
After a few recent flights of my Liberty 4, I'm looking at adding a Tether from http://www.defyg.com, a drogue chute and a parachute deployment bag for some dual-deployment/single-compartment fun.
Great post!
Thanks!!!
It did go well, in fact I went for L2 in the same day. Success on both! But I zippered the top of the tube on the L2 flight
Here is my post with pictures of the flights: http://mechanicalintegrator.com/?p=381