Big Daddy inspired

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GlenP

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I wanted to see what I could make from a body tube formed by a single full sheet of 8.5" by 11" cardstock, and came fairly close to a Big Daddy, which uses a 3" by 10" body tube. My diameter is 8.5" over Pi, about 2.7".

This has a 24mm engine mount and a 9" through tube inside with four cardboard centering rings to add some strength to the shell with a baffle near the top. I sort of made up the nose cone as I went along. The fins are balsa, cut from the Big Daddy plans and are through the wall.

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That's a fine design. I like it!:clap:
The originals are my favorites, even when and especially if they were inspired by something I can relate to or am researching flight characteristic wise.
I have a Big Daddy kit in the build queue, but I don't see what I'm missing about it being hard to do right.
It seems pretty straightforward, even when I do it my way in my head. The Openrocket likes it, and I can see the flight with clarity in my dreams.
Mine will launch from the 1500 Makerbeam that is slid into my 1010 rail. There will be none of this "Lawn Dart" nonsense going on when I fly that rocket!!!
I've wanted one since my early teenage years when all of the sudden Girls and Guns became way more interesting than Model Rockets.
Someone here graciously gave me one, and it's everything I though it would be, so I want to do it up right soon when I get a chance.
I'm not going to strip the glassine until the moment I start the build, and I'm not going to stop the building process until it is complete.


Best of luck on the maiden flight, and get a Video!



Engine placement must have been a tough decision with so little room for recovery gear.
When I do my BD, I'm going to take advantage of the room available inside the nose cone for the gear.
A BT-55 coupler will ride all the way to the tip of the cone, and the cone will sleeve onto that via a BT-55, with the recovery stuffs stuffed around it.
Glass, CF and general designer mayhem will ensue, but I already have taken pictures of some of the test components, and am about to test them at a much smaller scale on a different guinea pig of parts and materials.:)

Holy crap, I just realized that in the time it took me to type that, that "Hip To Be Square", by Huey Lewis and the News, played 4 times.:facepalm:

(You're not supposed to listen to it more than once every now and then. Thanks a lot stupid Tablet!!:mad:)
I must be wiped out from the heat!
 
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This was fun build, I didn't take pictures in progress, because I wasn't sure it was going to be a keeper. Here are some pictures fully assembled before painting and a shot of the inside of the body tube. You can see the 24mm through tube with the baffle. The through tube was built in parts, a 3" engine mount at the bottom, and a similar looking part at the top, joined by a 3" tube sized as an 24mm outer-diameter coupler to join those together. That way I could glue in the two centering rings for the engine mount, from the top and from the bottom, then attach the coupler tube to the top portion and glue in those two centering rings. The engine hook was cut from the metal strip from an old wiper blade.

To add a little rigidity to the body tube I glued 4 thin strips of paper equally spaced and parallel to the 11" side, one being the actual glue tab that holds the butt-joint together, kind of like a paper doubler/longeron. Also, around the top edge I added some more paper doublers to make the top edge a little stronger. I am still worried about zippering so I sandwiched the kevlar shock cord with some cardstock, not sure if that will do the trick or not. I may add a decorative and strengthening band of dryer duct Aluminum tape around the top of the body tube. Also, on the trailing and tip edges of the fins I wanted to add some strength with some paper strips to preserve the square edges. The leading edges are lightly rounded, but I like the angular look of the squared off fins.

With the boat-tail I have a little less base drag stability, and the engine mount is a little farther aft, so I put plenty of clay in the tip of the nose and coated it with glue. Even after coating the inside with glue, the entire nose cone is not as strong as I would like in between the seams and glue tabs, so I am thinking about putting a centering ring as a former for strength in the middle of the conical section.

PayloadBay.Com transitions:
Nose Cone tip:
d1=1mm d2=20mm L=10mm

Nose Cone:
d1=68.72mm d2=20mm L=6"

Boat tail:
d1=68.72mm d2=26mm L=1"

Nose Cone straight walled tube extension L=2" same as body tube dia.

Centering rings: d1=68.72mm d2=26mm
 
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I thought the nose cone looked kind of like a center punch, so I made a decal to go along with the impromptu build to make it look like it was planned all along. So, this cardstock approx Big Daddy shall be called: CENTER PUNCH. What size hole will we be making: 8.5/Pi diameter of course. Where? ... in the SKY!

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I really like the shape of the NC, but didn't place it as a center punch....I see it now. Nice name!
 
I got to maiden this one today, it flew great on a D12-5, my camera was totally out of focus on this one though. One interesting thing happened, on the boat-tail, I got some paint blistering from the plume heat. I think I will sand that down and re-paint with some high-temp BBQ paint. The large diameter base drag cavity just does not have much cool air flowing over the boat-tail, I guess. Compared to the Big Daddy, this hollow nose cone has plenty of room for the chute to be loosely packed and it deployed perfectly.

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Very nice indeed. You might consider doing a double lamination on your body and nose cone, it makes a big difference in strength. This is one of the few areas where I have found a use for the school glue stick. I'll lay on a good layer of the stick, then offset the two pieces of cardstock to create a glue tab. A length of PVC makes a good rolling pin, after it's rolled out, I'll use the pin on a soft surface,(usually my ottoman) to establish the curve of the tube and then finish with gluing the tabs together. It's a relatively quick process that makes for a much stronger tube. That long nose (which is pretty cool, by the way) would benefit from the lamination.
 
Nice! (BTW, I don't always build Big Daddy's, but when I do I cut the base off the nose cone. :))
 
Very nice indeed. You might consider doing a double lamination on your body and nose cone, it makes a big difference in strength. This is one of the few areas where I have found a use for the school glue stick. I'll lay on a good layer of the stick, then offset the two pieces of cardstock to create a glue tab. A length of PVC makes a good rolling pin, after it's rolled out, I'll use the pin on a soft surface,(usually my ottoman) to establish the curve of the tube and then finish with gluing the tabs together. It's a relatively quick process that makes for a much stronger tube. That long nose (which is pretty cool, by the way) would benefit from the lamination.

I thought about that, but wanted to keep it light. I do have thin strip doublers, one being the actual glue tab, then three more to add some extra thickness for the fin slots. There are several centering rings that hold the through tube, so the outer tube is fairly well supported. The long cone portion of the cone also has a centering ring/former about halfway through and a pretty healthy coating of white glue inside for stiffness, it is pretty durable.
 
Going through some old junk in the garage, I found some tools in a box that I had not unpacked from a prior move, and I found this center punch which bears an uncanny resemblance to this scratch cardstock rocket I built. Kind of a freaky coincidence, or a subconscious inspiration? I'll have to think about that when I get back from the Twilight Zone...

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Launch video from a few years ago. Nice large home-made chute brings this thing down slow...

 
When this thread resurfaced I thought "I've seen that one fly"....and there we are at the Raceway.....

That guy with the drone that you mentioned as you were videoing never did send me any video he took. *sigh*
 
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