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Fazor
2010-Mar-08, 06:35 PM
I'd been considering building a rocket for a while. I've decided to go ahead and do that. But every time I'd look at a kit, it just seemed so . . . well, already built. So I'm going from scratch. Here's to not blowing myself up. (I do sort of know what I'm doing).

Anyway, the building of said rocket is not so much what prompted me to start the thread. It's just a simple single small-engine tube rocket. The interesting thing will be seeing if I get the streamer to deploy correctly. Since I'm building it out of inexpensive materials, I won't lose any sleep if it doesn't.

The part I'm torn on is what colors to paint the rocket. I was going to go with the traditional white and black, with some red accent details. Then today I was thinking blue body with yellow nose-cone and fins, sort of like the retired "blue angels" fighters.

I had thought about doing all white with the UT logo on the fins, a-la the banner logo, but I think I'm going to save that for a second rocket, in which I try to mimic the swelled body shape. That'll surely end in catastrophic failure, but that's half the fun.

I like a simple two-color combination. What color scheme do you guys think?

HenrikOlsen
2010-Mar-08, 06:39 PM
Checkered white/red (http://images.google.dk/images?q=tintin+moon+rocket).

Swift
2010-Mar-08, 06:43 PM
Do you want it to contrast with the sky, when it is in flight, or blend in? If you want contrast, I'm not sure about the Blue Angels colors.

How about something really wild like purple and black with orange flames down the side?

Kaptain K
2010-Mar-08, 06:46 PM
Don't use pastels or solid white or you will lose sight of it agaist the sky!

mike alexander
2010-Mar-08, 06:46 PM
Basic white with cheap flame decals.

Kaptain K
2010-Mar-08, 06:47 PM
TSeeked by Swift. :(

Fazor
2010-Mar-08, 06:48 PM
How about something really wild like purple and black with orange flames down the side?

There's a good enough chance it'll have orange flames down the side without the use of detailing. :-P

Purple and black may work. I like the red/white checker idea too. If the later, I could christen her the "King Me!" or "Triple Jump"

cjl
2010-Mar-08, 06:51 PM
I'd been considering building a rocket for a while. I've decided to go ahead and do that. But every time I'd look at a kit, it just seemed so . . . well, already built. So I'm going from scratch. Here's to not blowing myself up. (I do sort of know what I'm doing).

Anyway, the building of said rocket is not so much what prompted me to start the thread. It's just a simple single small-engine tube rocket. The interesting thing will be seeing if I get the streamer to deploy correctly. Since I'm building it out of inexpensive materials, I won't lose any sleep if it doesn't.

The part I'm torn on is what colors to paint the rocket. I was going to go with the traditional white and black, with some red accent details. Then today I was thinking blue body with yellow nose-cone and fins, sort of like the retired "blue angels" fighters.

I had thought about doing all white with the UT logo on the fins, a-la the banner logo, but I think I'm going to save that for a second rocket, in which I try to mimic the swelled body shape. That'll surely end in catastrophic failure, but that's half the fun.

I like a simple two-color combination. What color scheme do you guys think?
What size rocket are you considering? There are many interesting kits available that aren't anywhere close to prebuilt.

As for colors, a combination of a dark color and a bright one is a good idea. Black, extremely dark blue, or similar would contrast well against a light blue or cloudy sky, while something like orange or yellow contrast well against the ground (so you can see it after landing).

Fazor
2010-Mar-08, 07:01 PM
Don't use pastels or solid white or you will lose sight of it agaist the sky!

Could remedy that with a vibrant chute or streamer, assuming it deploys (which of course is not a safe assumption).

The designer in me is curious about multistage rocketry, as well as devising different return mechanisms. But for now, my goal is simply to make something go "vwosh!" (preferably not towards my face).

Fazor
2010-Mar-08, 07:08 PM
What size rocket are you considering? There are many interesting kits available that aren't anywhere close to prebuilt.


I'm using this (http://www.jamesyawn.net/modelrocket/intro/index.html) as a guide. I'm just more inclined to build things from as little as possible.

HenrikOlsen
2010-Mar-08, 07:10 PM
The designer in me is curious about multistage rocketry, as well as devising different return mechanisms.
From what I've read, consistently successful multistaging is one of the holy grails of amateur rocketry.
Not for people who can't take failure.

Fazor
2010-Mar-08, 07:23 PM
If failure's a prereq, then I may be overqualified. :) I don't know where I'd fire a multi-stage rocket around here though.

Probably 20 years ago or so, a friend of mine's father would launch rockets at my parent's house. Plenty of space for that, but they were all single stage deals. Some more advanced stuff, IIRC (which I probably don't), but nothing that went too high.

cjl
2010-Mar-08, 08:39 PM
From what I've read, consistently successful multistaging is one of the holy grails of amateur rocketry.
Not for people who can't take failure.
Consistently successful multistaging is quite easy in the smaller sizes (A-D motor size range), but extremely difficult in the larger sizes. This is because the small motors can be set up such that the lower stage motor lights the upper stage directly, which is reliable and simple. The larger motors are more difficult to light, and must be lit from the top of the core, which necessitates electronic ignition. That is the main difficulty.

cjl
2010-Mar-08, 08:42 PM
I'm using this (http://www.jamesyawn.net/modelrocket/intro/index.html) as a guide. I'm just more inclined to build things from as little as possible.
That should work well to start. For other options, you might take a look at Fliskits (http://www.fliskits.com) and Dr Zooch (http://drzooch.com/rocketgallery.htm). They have interesting kits that actually involve significant construction, rather than simply snapping together a nearly-finished kit.

Fazor
2010-Mar-08, 08:50 PM
They have interesting kits that actually involve significant construction, rather than simply snapping together a nearly-finished kit.
I'll check that out. That's the problem; I started thinking about rockets one day when we were browsing around "Hobby Lobby" (large craft store, for those not familiar). They have a small section of rockets. Each time we go there, I'd check 'em out and debate whether to get one. But each time I was about to, I'd decide they were too preconstructed. Tube. Nose cone. Fins. All it looked like it involved was gluing the fins on, rigging the shock cord, and if desired, adding paint / decals.

Even if, end the end, that's all I'm really doing building it from scratch, there's something cool about starting with nothing but mundane materials and ending up with a launchable rocket.

cjl
2010-Mar-08, 09:00 PM
Yep. Fliskits also sells nice supplies for scratchbuilding - nose cones, engine mounts (they require construction, but all the parts come in a convenient package), body tubes, fin stock (thin, high-grade balsa), etc.


Oh, and if you are scratchbuilding and you decide to use wood for the fins, make sure the grain direction is running parallel to the leading edge of the fin. A common beginner's mistake is to cut the fins with the grain running parallel to the root edge, which is the weakest possible orientation and increases the chance of a shred or a fin breaking off on landing.

danscope
2010-Mar-13, 02:56 AM
If you are trying to deploy a streamer or parachute after acceleration, you might devise a simple mechnical catch that retains the module durring acceleration but uses a small weighted assembly to alter the catch under a condition of acceleraion, where upon once the rocket has stopped accelerating, it will now push the nose cone out along with the streamer or
parachute or both. Music wire can do it, along with elastic bands.
Get creative.
I'll be blasting you.

Dan

cjl
2010-Mar-13, 06:32 AM
If you are trying to deploy a streamer or parachute after acceleration, you might devise a simple mechnical catch that retains the module durring acceleration but uses a small weighted assembly to alter the catch under a condition of acceleraion, where upon once the rocket has stopped accelerating, it will now push the nose cone out along with the streamer or
parachute or both. Music wire can do it, along with elastic bands.
Get creative.
I'll be blasting you.

Dan
Interesting idea, but unnecessary. The rocket motors contain a charge to blow the nose off after a set time has passed after burnout.

Fazor
2010-Mar-13, 03:19 PM
I picked up most of the materials Monday but haven't started. Probably today; it's raining so likely I'll be stuck inside.

I haven't found any good material for the fins yet. The website I'm using (linked up above somewhere) said "modeling wood". I figured they'd have some in the rocket section of the craft store, but they didn't. In their woodcrafts section, they had a few blanks of some unknown type, but they were too thick and I don't have any tools that could rip them down. I'll have to check out the hardware store or something. It's not urgent; least not until I build the rest of the rocket.

Kaptain K
2010-Mar-13, 05:45 PM
Although it is not the only wood used in modeling, "modeling wood" probably means balsa.

cjl
2010-Mar-13, 07:34 PM
I picked up most of the materials Monday but haven't started. Probably today; it's raining so likely I'll be stuck inside.

I haven't found any good material for the fins yet. The website I'm using (linked up above somewhere) said "modeling wood". I figured they'd have some in the rocket section of the craft store, but they didn't. In their woodcrafts section, they had a few blanks of some unknown type, but they were too thick and I don't have any tools that could rip them down. I'll have to check out the hardware store or something. It's not urgent; least not until I build the rest of the rocket.
Typically, balsa and basswood are the best choices, but extremely thin plywood works well too. Fliskits sells good fin materials:

http://fliskits.com/products/components/fin_stock.htm

The plywood is stronger, but can be much more difficult to cut out with an xacto knife.

Fazor
2010-Mar-13, 07:51 PM
Although it is not the only wood used in modeling, "modeling wood" probably means balsa.

The site I list mentions various types of "modeling wood", but I assume the author was using the term to mean thin sheets of wood.

The ones the hobby store had were almost thin enough, but not quite.

I think I could make fins out of glue-hardened poster board if I really needed too. The advantage to a scratch-built rocket is that damage to the rocket isn't the end of the world. Though one that survives the ordeal is kind of an achievement. :)

cjl
2010-Mar-13, 09:41 PM
How thick were they, out of curiosity?

JohnD
2010-Mar-13, 09:49 PM
Paint, Fazor?
Paint = weight! Paint it and it will fly less high.

John

Fazor
2010-Mar-13, 11:02 PM
How thick were they, out of curiosity?

I'd say about 3/4" or so.

cjl
2010-Mar-14, 08:27 AM
I'd say about 3/4" or so.
That's definitely way too thick, yeah.

I'd say 1/8" is the thickest you'd want for low power (A-D motors), and in most cases, 1/16" or 3/32" would be fine too.

cjl
2010-Mar-14, 08:28 AM
Paint, Fazor?
Paint = weight! Paint it and it will fly less high.

John
It depends. In some cases, the paint gives you a smoother surface, and therefore less drag. That can more than counteract the increase in weight.

JustAFriend
2010-Mar-14, 09:07 PM
From taking my r/c planes out to speck-height, I can tell you that basic white with highly-contrasting blue or black is your best bet.

Any detailing (color stripes) for up close is fine, but mostly for your own benefit.

blueshift
2010-Mar-15, 03:49 AM
I would get a hold of Harry Stine's "Handbook of Model Rocketry" and "Second Stage Advanced Model Rocketry" by Michael Banks and Tim Van Milligan. Aerotech and Estes have some nice designs and some even take color photos at altitudes of several thousand feet.

Be careful Fazor, the hobby can really be addictive. I am still in recovery.

Fazor
2010-Mar-15, 04:22 AM
I would get a hold of Harry Stine's "Handbook of Model Rocketry" and "Second Stage Advanced Model Rocketry" by Michael Banks and Tim Van Milligan. Aerotech and Estes have some nice designs and some even take color photos at altitudes of several thousand feet.

Be careful Fazor, the hobby can really be addictive. I am still in recovery.

The hobby I'm really itching to start is knapping, but I haven't had a chance to go hunt up some suitable stone. The rocket thing was just a rainy-day something-to-do.

cjl
2010-Mar-15, 07:01 AM
The hobby I'm really itching to start is knapping, but I haven't had a chance to go hunt up some suitable stone. The rocket thing was just a rainy-day something-to-do.
That may be how it starts, but it's addictive, trust me. I'm rather thoroughly ensnared by the hobby...

(You might try going to a local club's high-power rocket launch sometime too - they're really awesome to watch)


Here's one of my larger ones (clickable thumbnail)
http://i27.photobucket.com/albums/c183/chris_lapanse/L2%20build/th_RL1D9306_crop.jpg (http://i27.photobucket.com/albums/c183/chris_lapanse/L2%20build/RL1D9306_crop.jpg)