Walt Disney's RM-1 Lunar Craft

For a long time I wanted to build a tube-fin model of Walt Disney's RM-1 Lunar Reconnaissance Craft. In fact there is a suggestion to this effect in the "Spaceship Handbook" by Jack Hagerty.



Also, some of you may know that there is a 1/33 scale paper model by Michael Vink, which can be found here:

View attachment RM-1.pdf

My first thought was to do my first card-stock using the paper model, but then I realized that the 1/33 scale is close to tube parts that are already available.

aerostadt said:

For a long time I wanted to build a tube-fin model of Walt Disney's RM-1 Lunar Reconnaissance Craft. In fact there is a suggestion to this effect in the "Spaceship Handbook" by Jack Hagerty.

View attachment 154731View attachment 154732

Also, some of you may know that there is a 1/33 scale paper model by Michael Vink, which can be found here:

View attachment 154733

My first thought was to do my first card-stock using the paper model, but then I realized that the 1/33 scale is close to tube parts that are already available.

Click to expand...

OK, I watching.

I apologize, Gordon. I just took a short break to watch the NBC Nightly News. Now back to business. I looked at the 1/33 scale paper model and saw that the tube diameters at this scale were close to LOC BT-2.14 tubing with has an OD = 2.26". So, I contacted Gordon The Sandman at Excelsior Rocketry to see if it could make the nose cone. Not only could Gordon make the nose cone, but he could also make the nuclear shield and other parts as shown below:



Gordon even included the round observation dome. I've laid the parts together loosely in the last photo as a dry fit trial of what things will finally look like. Actually, with Gordon's parts this model should be a piece of cake and it may still be, but I slowed down a little bit when the RocSim9 simulation showed that I had a stability problem.

I modeled this tube fin simulation on RocSim9 several different ways. Interestingly, enough if you look at the model closely with 7 external tanks, which are going to act like tube-fins, there is a stand-off distance from the main airframe and the tanks do not touch the main body. I ran the tube-fin calculator on Rocketry Reviews (formerly EMRR) and found that the inner diameter circumference for 7 tubes (OD=2.26") is 2.9488". There are least 3 ways to runs this model on RocSim9 as follows: 1) fins and tubes (no fin tubes), 2) 6 tube-fins that touch the main or center tube, 3) 7 tube-fins centered on a very short length of 2.9488" tube. The first model, although it looked nice, did not give me credible predictions for stability, so I am not using it. The second model may be the closest to being true, since it is a straight-forward application. However, the third method gives results similar to the second method, so it is probably not bad. Interestingly enough, both models predict stability problems, if all the tube-fins are heavy tubes. The 7 tube-fin model is worse than the 6 tube-fin model, probably because it has more tubes and, hence, more weight in the aft-end.

Examples for the RocSim9 6 tube-fin model and 7 tube-fin are attached here.

View attachment RM-1 Estes.rkt
View attachment RM-1 Recon Craft A-1.rkt

I found that there are 3 tubes from 3 different manufacturers that are all about the same diameter. The 2 heavy tubes are LOC BT-2.14 and the PML Quantum Tube QT-2.1 . The light tube is Estes BT-70. So, since I don't like spirals I am planning to use an 8.27" length of Quantum tube for the center tube and seven light BT-70 tubes of length of 3.125" each. Hopefully, the light BT-70's will hold up. I will need to roughen up the contact points of the Quantum tube in order to get a good bond between parts. The three different kind of tubes look this:

This is a very cool build! I'm watching

Thanks, Rocketgeek! With great care I hollowed out Sandman's nose cone with a 1/2 inch drill bit. This worked out pretty good. I have three 2 ounce weights from a fish tackle store that fit nicely into the nose cone. This should solve any stability issues.

rocketgeek101 said:

This is a very cool build! I'm watching

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I agree ,very different with many twists and turns.....I`ll be watching and learning !


Paul T

Thanks, Paul, for watching! I always appreciate your encouragement. I made some progress on the 24 mm engine mount today. I put a block of hard wood with a screw eye on the forward centering ring to tie in the shock cord to the airframe. I contoured this small wood block carefully on a scroll saw as to not cut any fingers and touched up the inner curved contour with a rat-tail file. I contoured the outer radius a little bit with a regular file. One time I had bad luck with 24 mm motor blowing out the aft end of a model during the ejection charge. So, I put in two motor clips for motor retention.

I eye-balled where the cockpit should go on the nose cone and glued it in place. I plan to paint some of the other parts separately and put them on the nose cone later. I put 2 coats of CA (fumes were bad) on the nose cone sanding with 400 sand paper in-between applications. So, far I have about 4 applications of MinWax water-based polycrylic finish (This stuff is my favorite. There are probably 20 other different ideas for this step.) sanding with 400 sand paper in between applications. So far this is working good. The Sandman (Gordon) made the radiation shield (the red part) out of hard wood, so it didn't need the CA, but I did apply about 4 applications of polycrylic followed with light sanding. The tip of the nose boom I masked and painted silver. I am painting the small observation dome silver, also. I may need to go back and do some sanding and re-painting on these silver parts.



Evidently, Von Braun and the producers of this concept envisioned that the silver tip out on the nose cone boom would be a nuclear reactor and the red radiation shield would protect the crew. It seems that somehow the nuclear reactor would supply heat to the rocket engine back at the rear of the vehicle. This was presented on the Walt Disney show back in about the 1954 to 1957 time frame. I may be off by a few years, but in any case back in those days nuclear power and spaceflight were so new that the general public assumed that anything was possible, so people didn't even begin to question such ideas.

Wait, what does Walt Disney have to do with the Rocket??? It's very cool by the way.

TopRamen said:

Wait, what does Walt Disney have to do with the Rocket??? It's very cool by the way.

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Check out 32:16.

[video=youtube;6eBoYB92nfI]https://www.youtube.com/watch?v=6eBoYB92nfI[/video]

Thanks Shrox, that was pretty cool.

Thanks, Shrox, I enjoyed the video immensely. I think Disney handled the special effects very well, especially considering that was about 57 years ago, long before the sophisticated computer animation that we have now. BTW I stand corrected. The nuclear reactor in the nose tip provided electrical power to the ship. The chemical rocket was powered by nitric acid and hydrazine.

COOL Build!!!
Colors?

Scotty Dog said:

COOL Build!!!
Colors?

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Thanks, Scotty! The predominant color will be white with red for the radiation shield and a few silver parts. Actually, the final model will be fairly small, short and stubby in my opinion. There are a lot of features that can be added for static display and are readily available from the paper model (or card stock), because the paper model is the same scale. One can add covers for the tanks (tube-fins), piping and bracing for the tanks, the aft rocket engine, the pod-suit, and the radar antenna.

Scotty Dog said:

COOL Build!!!
Colors?

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Actualy the color is light grey, look at the color description in the book. Oh, by the way....THE RACE IS ON !!!!! I'm building one too.

I,m liking this. What a great build subject!!!

hornet driver said:

I,m liking this. What a great build subject!!!

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I think it is a good subject, too. Watch the video that Shrox supplied, especially the latter half where von Braun picks up.

Actually the color is light grey, look at the color description in the book. Oh, by the way....THE RACE IS ON !!!!! I'm building one too.

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Scotty Dog, you might win, but you are spurring me on. I figured I better do something tonight. I looked at the fin template maker on Rocketry Reviews (EMRR) in the features section under tools (the old tools) and marked location for the 7 stand-off pieces made out of 3/32" plywood. My calculations put the stand-offs at 0.35" wide and I made them 2.25" long just a little bit shorter than the BT-70 tubes, which I cut at 3.125" each. I tacked 3 pairs of the tubes together lightly with wood glue with one tube left over. These BT-70 tubes are very light. I hope that the points of attachment will toughen them up for flight. I am sanding the Quantum Tube at the stand-off contact points to improve the epoxy bond.

Yes, I see now that the color is light grey in the book and it looks good in the photo. Nevertheless, I think I will go with white epoxy paint, since I have a can already and I like the results that it gives.

Here is my effort so far Our team of scientists are working on the problem of stability, MENTAL!!!

kpklein said:

Here is my effort so far Our team of scientists are working on the problem of stability, MENTAL!!!


View attachment 155266

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Looks great,kpklein! I like the position of the cockpit. I think that I put mine too far aft. How did you make the nose cone, radiation shield, and boom? How did you make the tanks?

The competition around here is getting tougher. I better work faster.

Thanks aerostadt, the nose cone and BT are from a box of odds-n-ends someone gave me a long time ago. The shield is formed from card stock (poster board), the boom is a bamboo squer and the tanks are made from card stock just rolled around a suitable size tube and lap joined. I am not intending to put too much into this one incase it does'nt work. If it flies okay, I might cover the ends of the tanks and see if the drag will be enugh to make it stable, although at an unnessecary expence of propellant. Shuld be fun.

Yours looks like it will be better made.

I made some more progress today putting on the struts for the attach points of the tube-fins (tanks). In between two struts is a hidden launch lug for a 3/16" rod.

That is exactly How I did my strut attachments, the stars must be in alignment. There are a few things I discovered with my project. First, the reactor boom is too long, in the Disney film it shows as shorter, also in the book Dream Machines it is depicted as shorter. I cut it off and replaced it with a shorter one and looks much better, except the redrilled hole is a little off center.
Second, there should be a window on top of the canopy. Third, The diameter of the radiation shield is greater than the diameter of the central tube, so the launch rod will not clear it without scraping or binding. I cut a notch in the shield but you could reposition the lug further out ,but that will put a binding motion on the rod maybe. There is RM-1 shown on the sides in the Disney film. The last observation is that the proportion looks a bit longer in the drawing than what the others appear in the film or Dream Machines book.

Carry on.

kpklein said:

That is exactly How I did my strut attachments, the stars must be in alignment. There are a few things I discovered with my project. First, the reactor boom is too long, in the Disney film it shows as shorter, also in the book Dream Machines it is depicted as shorter. I cut it off and replaced it with a shorter one and looks much better, except the redrilled hole is a little off center.
Second, there should be a window on top of the canopy. Third, The diameter of the radiation shield is greater than the diameter of the central tube, so the launch rod will not clear it without scraping or binding. I cut a notch in the shield but you could reposition the lug further out ,but that will put a binding motion on the rod maybe. There is RM-1 shown on the sides in the Disney film. The last observation is that the proportion looks a bit longer in the drawing than what the others appear in the film or Dream Machines book.

Carry on.

Click to expand...

Thanks, kpklein for the update! Yes, I checked the guide wire and it does interfere with the radiation shield as you said. I have glued the radiation shield in place with CA. I think I will probably put on a launch lug a little bit further out from the body. I think you may find different versions of the R-1 depending where you look on the internet. Some show a round observation dome on the cockpit. I noticed that the paper model shows a blue dot on the top of the cockpit. In the Walt Disney movie it looks like their is a clear observation dome on top. Sandman made me a small round dome which I have painted silver. I think I recall seeing a clear spotlight dome on the bottom of the nose cone. Some of my tube fins were not quite touching, so I tacked them in place by using paper clips and yellow carpenter's glue.

aerostadt said:

Thanks, kpklein for the update! Yes, I checked the guide wire and it does interfere with the radiation shield as you said. I have glued the radiation shield in place with CA. I think I will probably put on a launch lug a little bit further out from the body. I think you may find different versions of the R-1 depending where you look on the internet. Some show a round observation dome on the cockpit. I noticed that the paper model shows a blue dot on the top of the cockpit. In the Walt Disney movie it looks like their is a clear observation dome on top. Sandman made me a small round dome which I have painted silver. I think I recall seeing a clear spotlight dome on the bottom of the nose cone. Some of my tube fins were not quite touching, so I tacked them in place by using paper clips and yellow carpenter's glue.

View attachment 155405View attachment 155406View attachment 155407

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Actually, the dome I made you was sort of a Pattern. I thought maybe, I should have mentioned it, could be used to make a clear bubble using some clear plastic canopy material, heating it up and pulling the softened plastic over the part I made.

Just a thought I had. It wouldn't use much plastic.

Heck, I may have some.

Thanks, Gordon. I have masked off a location on the cockpit top where I plan to put the dome after painting the ship with white epoxy paint. Actually, I don't mind a silver dome. I just looked at Hagerty's book and it shows nothing on the right side, neither R-1 or RM-1. I have already ordered the decals from Sticker Shock, so I am going with R-1. I did not look at the movie close enough to pay attention to the RM-1. I still need to go back and strengthen all the tank joints with epoxy. That will take time.

I have the "Man in Space" on DVD.

In the show the navigator sticks his head up into the dome and checks their position with a sextant.

So...it's clear.

Look at this video,

https://video.search.yahoo.com/vide...sigr=11ac1a3a7&sigt=119c29hcf&age=0&b=61&tt=b

At about 1:26. The dome is clear.

And a ton of close up details of the model.

sandman said:

I have the "Man in Space" on DVD.

In the show the navigator sticks his head up into the dome and checks their position with a sextant.

So...it's clear.

Look at this video,

https://video.search.yahoo.com/vide...sigr=11ac1a3a7&sigt=119c29hcf&age=0&b=61&tt=b

At about 1:26. The dome is clear.

And a ton of close up details of the model.

Click to expand...

Gordon, There is no way that my model is going to look as good as Walt Disney's and von Braun's model. The detail on that model is gorgeous. I did find that I can cut off the end of a soft pipette to make a clear dome. Now I am torn between the clear dome and the silver dome and I am not sure which one to use.

I found another launch lug and I have move it further out on the inside of one of the tanks.

aerostadt said:

Gordon, There is no way that my model is going to look as good as Walt Disney's and von Braun's model. The detail on that model is gorgeous. I did find that I can cut off the end of a soft pipette to make a clear dome. Now I am torn between the clear dome and the silver dome and I am not sure which one to use.

I found another launch lug and I have move it further out on the inside of one of the tanks.

Click to expand...

The dome probably was envisioned as having a retractable cover or an internal sunshade.