What did you do rocket wise today?

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Did the outside fillets of the Pink Lady's centering rings. Tomorrow, I'll sand the centering rings so the motor mount can easily slide in and I will cut a slit at the aft end of each fin slot bas well as sand the fin slots to open them up a little bit.
 
Now I need to do the fins. I think they will have to be very large. My current thinking is an 8 to 12" root and a 24 to 36" span. From the BT to the edge of the P-O-P is 12". I think there will be a lot of turbulence around the fins as this brick goes up. So a large span is needed to get some of the fin into clean air. Does anybody have an opinion on the fin size?
Not an actual opinion on the answer, but a thing to consider. Are you planning to extend the fins grom the face centers, or the corners? Going out to the corners from the center is about 40% longer than going to the edges. but you might not need as much extending beyond, because there it might be easier to reach clean air in that direction. Or it might be harder, I really don't know. But it's worth taking such things into consideration.
 
I am revisiting some of my early V-2 A4 designs. A BT-60 based V-2 A4 was actually the 1st rocket I made from 3D printed rocket back when I first got started.

Anyway, my main motivation going back to these designs is because I am considering making an A-10 to A-4b or A-9 two-stage model rocket. I was thinking BT-80 for the A-10 + it looks like BT-50 for the A-4b/A-6 to be semi-scale. I saw that a one or two people have scratch built these over the years but seems like a really interesting design for a two-stage rocket with a clamshell enclosure for the sustainer.

1669581461326.jpeg

Came across this interesting little piece of Trivia -- apparently the A-4b / A-6 is considered inspiration for the X-15.

1669581398648.png
 
Last edited:
Drove through numerous showers to come home from GRITS. Yesterday GRITS had a ceiling that rose and fell through the day. Generally, it was around 1000 - 2000'. I flew the Interceptor on its maiden flight on a C6-5. It held together, so I launched it on a D16-6. The performance was greatly improved and it is still intact.
Other rockets I flew:
Aerobee Jr. : F12-5J
The Amazing Point: C6-3
Mars Lander D20-4
Dr. Zooch Saturn V C6-5
Scratch-built "Mustard & Catsup" 2 stage C6-0/B6-6
 
I cut out 3 of the four fins for the Port-O-Potty. Ran out of plywood. I though I had enough. I ordered 4 each 6" x 36" again. When I place that kind of order BMS is kind enough to give me one 2' x 4' piece. I'll get one more fin out of it and have some left over for other projects. Besides the plywood I ordered a couple of 3" nose cones, some 3" bulkheads and some 3" tubes. Because I order so much from them I'm glad they are just around the corner. I also sanded four fins for a 3" rocket I'm working on. Yesterday I cut them out and shaped them with a belt sander. Then coated them with GoodFila CWF and sanded them smooth with my random orbit sander. After that I sanded them with 400 grit by hand. Looked for imperfections in the sun light and sanded them out. Later today I'll put them on the rocket. The Port-O-Potty fins will just be sanded and the grain will not be filled in. The Fins are 12" x 30" x 1/4" in a clipped delta planform. I'll get the three fins sanded later today too. Yesterday I made an av-bay for the 3" rocket, added rail buttons and cut the fin slots. I cut the fin slots with a Dremel and a reinforced cut off wheel. Cut all 4 slots in a couple of minutes. When through the LOC tubes easily. Tomorrow I'll pick up my order from BMS and cut out the 4th fin. I'll try to install them tomorrow. A coupler bulkhead and coupler were put together. I cut a hole for an EggTimer Apogee in the bulkhead and added a welded eye nut to it. The coupler will get a 4" plastic dome added for a nose cone. Rather than ejecting the whole roof, just the 4" nose cone will be ejected. The chute will come out of the center of the roof so the whole intact Port-O-potty come s down under it. I'm going the attach the fins all the way at the end of the BT. I hope to land the Port-O-Potty up right. I will probably fly it at our SpringFest in March. I'll store in it in our storage unit until then. It's way to big for our garage. And that's all the rocket news from Pahrump.

Dave
 
I put some Krylon 2 in 1 primmer on the 3" rocket. I started putting the fins on the P-O-P rocket. I'm putting them on one at a time. I got the first two on and my wife comes out to the garage and said "Those are some big fins. How are you going to transport it". My mind came to a sudden stop. Oh, Oh. There is no way it will fit in the Explorer. I'll have to put it in my '94 Ranger. I don't really trust it going out to the Jean dry lake. I would probably have to put new tires on it. The ones on now look new. But are about 5 years past there use by date. Yes, tires expire. It was news to me. Maybe just rent a trailer. It's 80" fin tip to fin tip. Maybe a truck.
 
Bought some shelving for the work shop. Pretty good deal; Home Depot price is about double.

https://www.walmart.com/ip/Muscle-Rack-Black-48-W-x-24-D-x-72-H-5-Shelf-Steel-Shelving/21685762
I bought some shelves very similar to that a few years ago at Lowes. Made a dolly out of 2x4s to fit under the frame and put casters on it so I can move them around. Also replaced the particle board shelves with 1/2” plywood. That particle board will sag under its own weight.
 
Nice rocket, and very nice instructions from what I see in the ad. 👍

Thanks for the compliments. We had a lot of releases planned for this year, but three floods and a major Covid outbreak knocked that on the head. Just feels good to tick 'Cluster kit' off the list.
 
Cut the aft end off the nosecone on my LOC Magnum and glued in a 4" bulkhead with an eyebolt. Gonna let that cure 24 hours and then I'll sand it with 80grit and add a layer of milled fiber reinforced epoxy over the bulkhead. Then the rocket will be done except wiring the av-bay and paint.
 
Back
Top