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DavidQ
10th January 2012, 10:41 AM
I've wanted to build the 2001 Discovery for a long, long time. Finally, a found a superb card model online by UHU02.

That model has now found a home in my home.

I decided to upscale the model, so that it would have a spine the size of a BT-20 tube, instead of a smallish 9mm spine. This, however makes for a BT20 sized rocket that is on the order of 7 feet long, which, as we can guess, presents some interesting engineering challenges. But, being one to rationally disregard obvious concerns, like that of trying to launch a skinny rocket with a relatively weights on the very ends and that will osscilate like a plucked piano string, I decided to just jump in.

I'd like to share the model, but the author has insisted that he be able to make it hard to find. I'll point out that if you want it, you can join the zealot card modeling site, do a search of UHU02, and follow his hints.

The original plans come on about 24 sheets of cardstock. But, since I'm upscaling it by 2.3x to get the BT20 spine, I'm taking many more. I've not counted how many, as that's a piddling detail that is unrelated to deciding to build, to building, or to looking back on what I built. Actually, I'm not finished with the upscaling, so don't yet know how many sheets it will take.

Additionally, I modified the images slightly. I don't like solid black lines for the cutout lines. I think it highlights the wrong part of the model. I want attention drawn to the places I didn't cut, instead of the edges that I did cut. So, I modified each of the black edges to be light gray edges.

Here is some of my progress, starting with the construction of the spine. It stands taller than my home-built photo studio, which is about 4 feet tall (1.3 meters for the furriners in the audience). The spine is not much more than a bundh of BT20s attached end-to-end, with wraps which will indicate where other pieces will go.

DavidQ
10th January 2012, 10:45 AM
After the spine was assembled, dried, and touched up where the seams came undone a bit, come the mounting brackets for the cargo containers. I didn't even realize that the Discovery had cargo sections. But, that's what that long section between the ends are.

There are 33 rings that are printed, cut and folded to hold 33 cargo sections, each arranged in groups of three.

DavidQ
10th January 2012, 11:03 AM
Attached to these rings are the cargo bays. They are arranged in triplets around the spine, in groups that are about 4 inches long. Some cargo bays are 4 inches long, some are in pairs 2 inches long, and others are in 3.25" and .75" units. (If you are in a metric nation, that's 3.25 inches and 0.75 inches.)

I attached these in a straight line by laying the cargo bays on the ground against a piece of shelving material held parallel to the spine. It ended out pretty darn straight.

DavidQ
10th January 2012, 11:15 AM
It just occurred to me that there are likely tots in the crowd that for some reason, weren't of a movie watching age in 1968, and are unfamliar with the book, movie, and cultural meme that was 2001 A Space Odyssey.

Here is a google search for pictures of the main ship, the Discovery (http://www.google.com/search?q=2001+a+space+odyssey+discovery&hl=en&rlz=1T4GGIH_enUS237US237&prmd=imvns&tbm=isch&tbo=u&source=univ&sa=X&ei=Ig4MT7-BD8_RiALU25iMBA&sqi=2&ved=0CCAQsAQ&biw=1016&bih=632).

Here's also a picture I found on the web.

I'm planning, if it works out, to avoid any fins on the bottom. I'm hoping that the engine compartment will work as well as the tiny fins on a Mean Machine, especially if I put enough mass in the pod bay door section at the top.

dlazarus6660
10th January 2012, 02:45 PM
Nice build, can't wait to see it fly! Check your #3 post on the metric measurments.

dixontj93060
10th January 2012, 03:27 PM
Cool!

tbzep
10th January 2012, 03:41 PM
I hope HAL likes it. :eyepop: :D

Montaro
10th January 2012, 04:29 PM
This will be a cool rocket !!!

DavidQ
10th January 2012, 07:21 PM
Check your #3 post on the metric measurments.
But... 3.25" is 3.25 inches in metric nations. Meaningfulness in a metric nation is a different topic :)

Did you know that they have the 4th of July in England, too? :)

Montaro
10th January 2012, 07:42 PM
But... 3.25" is 3.25 inches in metric nations. Meaningfulness in a metric nation is a different topic :)

Did you know that they have the 4th of July in England, too? :)

Don't worry David, we understand " = Inch and ' = Foot , but we don't understand why you still using english units :D ... just kidding !!!

About Systems of measurement somebody know which system was used in the ISS design ?

DavidQ
10th January 2012, 08:29 PM
but we don't understand why you still using english units ... just kidding !!!
I suspect its because we've got enough people that are afraid to try out the future until its already been proven to work here. And that takes time. So go ahead and finish your phase one trials on your based-ten approach to measurements. Let us know how that works after you've had a little time - like nearly 200 years - to see if it works better than our highly refined mixture of base 12, base 2, base 60, base double-it-and-add-thirty, and some base 10.

Montaro
10th January 2012, 10:27 PM
I suspect its because we've got enough people that are afraid to try out the future until its already been proven to work here. And that takes time. So go ahead and finish your phase one trials on your based-ten approach to measurements. Let us know how that works after you've had a little time - like nearly 200 years - to see if it works better than our highly refined mixture of base 12, base 2, base 60, base double-it-and-add-thirty, and some base 10.

all the countries have a mixture, here in mexico we use PSI, nobody use pascals, and we use kilos for weight and should be kilos for mass and newtons for wieght. and is almost impossible to change!

but some country are to complicated like Puerto Rico, the distance are in Kilometers and the Speed in MPH, if you want to buy a house the land is in sq yds and the building is in sq meters. :y:

DavidQ
23rd January 2012, 08:26 AM
I've made progress on the 2001 Discovery card model I'm upscaling and assembling to be flyable (I hope).

This time, the engine section has been added.

The Discovery has six engines, so I made it hold six 18mm engines. As is seen in the photos, the six engines are grouped into three clusters of two, as per the model design. I made the outer pairs of engines into blunt tubes, so that at ejection, those four engines will just pop out the back. These tubes are coupled to some BT20s that extend into the engine compartment to more easily transfer the force to the spine. The central two engines are coupled to the BT20 that runs up the length of the spine. The exhaust coupling is hidden inside of the hexagonal engine fairing. The exhaust from those two 18mm engines is routed up the spine, so that it will eject the nose way, way up top. That's over 8 feet away, it turns out.

Each of the three fairings for the engines are mounted to the engine section with a 16" section of BT20. This BT20 is then coupled to some internal reinforcing that I used to strengthen the engine section. It is visible in the photo under the flap which is not yet glued down. Each of these three BT20 tubes are attached to internal balsa via some CR2060 centering rings, so as to provide more strength, and to better transfer the thrust up the spine.

I am, however, getting worrid that the spine will be too flexible, and with the mass on each end, might fold under thrust. I'll think about that more.

dlazarus6660
23rd January 2012, 09:15 PM
You might want to consider using CFR's for strength. Think 'dowel'.

DavidQ
24th January 2012, 02:02 AM
OK, so I just got back from the hobby store with two pieces of 4' x 0.35" hollow carbon fiber rod. That is pretty stiff stuff.

I'll put a spine inside of the spine. My earlier thought had been to mount BT5 inside of the BT20, although I didn't expect a lot of added strength. But, it would have left about 3/4 sq in cross section for the exhaust to flow, down from about 1.5 sq in. This way, I've got over 1 sq in cross section for the exhaust, so I'm happier.

Thanks for the idea, dlazarus.

Bazookadale
24th January 2012, 02:43 AM
Don't worry David, we understand " = Inch and ' = Foot , but we don't understand why you still using english units :D ... just kidding !!!


Be a cold day in hell when we change to the French system!:kill:

plano-doug
24th January 2012, 02:57 AM
I suspect its because we've got enough people that are afraid to try out the future until its already been proven to work here. And that takes time. It's more an issue of demand than fear. If I don't need to speak French, I won't learn it. Someday, if things keep going the way they are, I may need to speak Spanish. But for now, there's so little demand on me for that, I haven't bothered to learn it.

Same for learning the metric system. I had to learn it to get thru engineering school. And can convert back and forth between the metric and imperial systems with ease.

But as long as your mom is able to buy hamburger by the pound, as she's done for many years, she's not compelled to learn anything about mass/weights using metric units.

Folks learn what they have to. And as long as the old, comfortable imperial system remains in use here, folks won't be in a rush to go metric.


Doug

.

foamy
25th January 2012, 04:52 PM
A big discovery will provide us a lot of creativity so we will get a best resources and be happy in all matters so getting a best role and be cooperative for promotional aspects.
Somebody found my magic eight-ball. Either that or you're reading a lot of fortune cookies.

Cosmotiger
25th January 2012, 05:25 PM
Somebody found my magic eight-ball. Either that or you're reading a lot of fortune cookies.

The future is unclear. Ask again later. :rolleyes:

PhlAsh
25th January 2012, 10:42 PM
Folks learn what they have to. And as long as the old, comfortable imperial system remains in use here, folks won't be in a rush to go metric.

.

Living in Wales in '93, I remember watching Sky's version of CSPAN. Someone in the House of Commons suggested that it was time for butter to be sold by the half-KG and beer be sold in pubs in half-Litres. They nearly ran that guy out of the place!

hornet driver
1st February 2012, 05:04 AM
That's a very GUTSY and great looking build. Buddy , that took a lot of time and work. Hope it flys straight with no issues. Just lookin at it , Id say-you got no problem except--you might want to "open the pod bay doors Hal"

DavidQ
4th February 2012, 11:48 AM
Id say-you got no problem except--you might want to "open the pod bay doors Hal"
But.... My name's Dave. He can't do that for me!

I'm almost done with the front section. That's taking a lot of time too. Pictures to come in a couple days, I hope.

JPVegh
5th February 2012, 10:47 PM
(If you are in a metric nation, that's 3.25 inches and 0.75 inches.)



Yeah, but what is that in AUs?

DavidQ
7th February 2012, 06:36 AM
Australian Units? Do Aussies measure everything in terms of how long earth will survive once the sun explodes, about 8 light minutes? ;)

I prefer to measure in the MITS system, i.e. the system based on Smoots (http://en.wikipedia.org/wiki/Smoot). The rocket is almost 1.6 smoots tall already.

------
Progress update.

I'm getting the front ball assembled. In the original plan, its essentially a ball made from stacks of frustums. Really low strength when it is upscaled as large as I've made it. In fact, it's about a foot across (about 0.1 nano light-second), made from presentation paper.

To add some strength, and some mass, to the structure, I cut large rings for each of the strips, from matte paper. I put a 4" hole in the middle to eventually couple each of the rings together with a 4" body tube. In the picture, the tube is still long, since I don't yet know how long it should be.

dlazarus6660
22nd April 2012, 12:52 PM
It's been almost three months since you did a pot on this Dave.
Dave, are you angry with me?
Dave.
Dave, what are you doing?
I'm losing my memory, Dave.
Dave.

DavidQ
23rd April 2012, 10:41 PM
Three months! Man, I got distracted.

It's still sitting in the living room, head detached from the rocket but nearby.

I've been waiting for the rains to stop - finally I think we're there - so I can take it outside and mount the carbon fiber rod into the spine. I also need to test out a side-eject system I think I'll put in the head. Testing it in flight would be a bad idea.

dlazarus6660
11th May 2012, 11:13 PM
http://www.youtube.com/watch?v=ukeHdiszZmE

Rocketbuilder
12th May 2012, 04:29 AM
If the problem is structural issues with the spine, maybe you should make a big Leonov and tie them together for structural reinforcement. :p