October Sky

[MarkB.]

A couple of months ago, I talked about an R-7 build thread for the upcoming 50th anniversary of manned space flight. My ADHD kicked in and I got side tracked rebuilding a Maxi V-2, but now I'm running out of time to be ready by April, so here goes.

We're going to end up with a 1/63rd sport-scale, 24mm powered, R-7 that can be used to model Sputnik, Vostok and Soyuz.

I'm going to divide this build into two sections: the basic R-7 booster build and then the open framework/Vostok build which will be the nosecone section for our booster. I promise this will be a lot easier than you think and given the beautiful rockets displayed on this site, well within the capacity of all but the most novice builder. If you've made a paper boat tail, you can build this model

Generally, I'm going to follow Peter Alway's Art of Scale Model Rocketry plan with some "improvements". All of the shrouds and the custom ring are drawn using the Template Widget from the EMRR site.

For those scoring at home, here's what we're going to need for just the R-7 booster:

4 2.5" sections of BT-60;
4 9" sections of BT-20; (edit: make it 9.5 ")
4 Semroc BNC-20SU;
4 .375" sections of BT-60 coupler;
8 6020 adapter rings;
4 cardstock shrouds from BT20 to BT60 with a central length of 6.5 inches; (edit: make it at least 6.875" and 7" is better)
1 small piece of 1/16" bass or ply sheet to make fins;

The foregoing will be turned into the four strap-on boosters; if you're the fire-breathing, steely-eyed missileman type, you could add a motor mount to these, but I'm not going to . . . .

The core needs:

1 14.5" section of BT-55
1 3.5" section of BT-60
1 24mm BT-55 motor mount
2 6055 adapter rings
2 heavy cardboard adapter rings BT-55 to 1.82" outside diameter
1 cardstock shroud BT-55 to 1.82" diameter with a central length of 2.875"
1 cardstock shroud BT-60 to 1.82" diameter with a central length of 3.5"
4 1/16" x 1/8" x 7" balsa strips
1 1/4" x 1/8" x 18" balsa strip
1 1/16" square x 24" spruce strip (edit: make it 1/12 round dowel)
kevlar/elastic shock cord
sheet of Chrome Monokote Trim
20" parachute
1 can Testors European Gray spray

I got all the rocket parts from Semroc and the strip stock from Hobby Lobby. The Chrome Monokote trim (adhesive backed) is from Balsa Machining Service. I'll start with the strap-ons later today. This is going to be a real-time build thread so be patient . . . .

Unless you fly with Peter Alway or Chan Stevens, you'll be the only Vostok at the field come April.

On last thing, if you want a super-accurate R-7, order one of Sandman's kits; they are beautiful.

[Bill]

Are those plans currently available for download on the 'net somewhere?


Bill

[dlazarus6660]

I know they are in a Sport Rocketry mag somewhere(Mar/Apr'96).
Peter Alway Simplified Vostok 1/100 scale. Using a BT-50 and paper shrouds.

[MarkB.]

Actually, its a BT-55 based rocket at 1/63 scale. And I haven't forgotten . . . its just that life intervened.

I looked at NARTS and ARA Press, and as far as I know, the Art of Scale Rocketry Vostok plan isn't available right now. The book is listed every once in a while on eBay for about 20 bucks and in my opinion, must be part of any scale modeler's library. I don't know if Peter Alway checks this site but I know that there are guys that fly with him here. Maybe he can agree to have the plan published here while I do a build thread over the next few weeks that mostly follows his plan.

I promise to have the first of the build pictures up by Sunday night. We're going to start with the strap-on boosters.

[Bill]

Are those plans currently available for download on the 'net somewhere?



To answer my own question, http://www.rocketryonline.com/jimball/alway/plans.htm


Bill

[blackshire]

I know they are in a Sport Rocketry mag somewhere(Mar/Apr'96).
Peter Alway Simplified Vostok 1/100 scale. Using a BT-50 and paper shrouds.Peter Alway's Vostok plans (the simplified ones, I think) are also in his lesser-known but excellent book The Art of Scale Model Rocketry. If NARTS (NAR Technical Services, see: http://www.nar.org/NARTS/ ) doesn't have it in stock, copies may be available from used book sellers such as AbeBooks.com www.abebooks.com and Alibris.com www.alibris.com . Used books are also sold on eBay www.ebay.com , Half.com http://www.half.ebay.com/ , and Amazon.com www.amazon.com. If you'd like to get a copy of his "Magnum Opus" book Rockets of the World, these sources might also have it.

[MarkB.]

My apologies to Bill.

There are two different Peter Alway plans for a Vostok. The link above, which I assumed was the same as the one in The Art of Scale Model Rocletry, is in fact different. The link above will build into a 1/100 scale Vostok on a BT-50/T-25/#9 body tube. I have not built this one but I've never built one of Pete's plans that didn't fly.

Hopefully, Pete will put the larger plan on his site as well. I'm going to build based on the larger plan.

Again, my bad, Bill.

[Bill]

There are two different Peter Alway plans for a Vostok. The link above, which I assumed was the same as the one in The Art of Scale Model Rocletry, is in fact different. The link above will build into a 1/100 scale Vostok on a BT-50/T-25/#9 body tube. I have not built this one but I've never built one of Pete's plans that didn't fly.



I was so happy to find that page I posted the link before I had a chance to actually look at the plans. Because the other plans on that page are from his book, I naturally thought this was the same. The search continues. It would be nice if NARTS is able to reproduce that book like it does the Army Missiles of the Cold War.


Bill

[MarkB.]

As promised:

Picture 1 shows basic parts for the build up of the strap-on boosters. (technically, I believe them to be the first stage like on the contemporary Atlas, but I digress). It took about an hour to cut the lengths of BT-60 and coupler stock with my X-Acto saw, as well as cut out the shrouds from cardstock and trim and sand the nose cones.

Picture 2 shows the parts for one booster.

Picture 3 shows the initial assembly: one 2060 ring on the base of the BT-20 and the other under the coupler length in the BT-60. At this point, I set it aside to dry while I assembled the other three boosters to the same status. By the time I finished the other three, the glue had set well enough on the first to glue the BT-20 and ring through. Total time: 30 min.

Note: if you want to cluster simply add an engine block to the BT-20. I didn't.

I then took a deep breath and started on the tough part: Origami - making shrouds. I carefully glued the first shroud. Because I intended to hide the joint by attaching that side to the core, I didn't have to get nuts about a super smooth joint.

The first one didn't come out very well -- In fact, I threw it away. I took a breather, mowed the front lawn and came back. I cut out a replacement and glued them together and taped the joints using low-tack masking tape and a little help from my son. I set them aside to dry while I cut the back yard. Total time: 40 minutes.

Picture 4 shows the almost completed boosters. The nose cones are glued on at this point. Trimming and glueing the shrouds took about 30 minutes only 'cause I trimmed for as close a fit as possible to minimize the need for putty later.

All that they need at this point are the mounting strip and the little fins which we'll add at final assembly.

[MarkB.]

Alrighty,

Here's the next installment of my sport scale Vostok build. First a disclaimer: I suck at all things paper -- boat tails, shrouds, transitions and wraps. By golly if it's made out of paper, I'll screw it up.

In the last installlment I did the initial built up of the strap-ons. This time we're going to work on the core.

Before starting, make sure you mark six lines on the BT-55, one for each strap-on and then two opposite each other centered between the strap-on lines fro the lug and the big conduit.

Picture 1 shows the top section of the core: you are looking at the BT-55 core, the hand cut cardboard BT-55 to 1.82 shroud support and glued to the front of that is the BT-55 to BT-60 ring. At the very front is a second BT-55 to BT-60 ring. There is approximately 1.5 inches between the 5560 rings

Also in the picture is one of the strap-ons with the piece of 1/16 x 1/8 balsa standoff. This strip is glued immediately adjacent to the seam on the paper shroud and hids it very well .

Picture 2 shows the 3.5 inch piece of BT-60 glued over the rings with the shrouds in the background.

Disclosure - at this point "dry" fitting the core shrouds indicated more surface area was needed at the widest point so I cut another cardboard ring (out of a Priority Mail box) and stacked them.

Picture 3 shows the now shrouded top end of the core. This is THE finest work I have ever done with paper shrouds: seams line up, no fingerprints in the glue, no wrinkles .

Yaa-Hoo!

Also note that I have glued a paper disk to the bottom of the strap-ons.

Disclosure: I had to cut out a second set of shrouds 'cause I screwed the first set up gluing them on.

Note that I have not yet installed the engine mount, and good thing too. Dry fitting the strap-ons indicates that some trimming of the bottom end of the core will be necessary to get everything to look even. Also, it appears the the nose cones on the strap-ons which Peter had indicated to be 2.5 inches long are a little too long at that length. Although I have already filled and sealed the cones, I'm probably going to go back and trim them at least another 1/8 to 1/4 inch.

[MarkB.]

If anybody's actually reading this thread . . . .

FABULOUS NEWS!

SEMROC has come to my(our) rescue. As you know from the post above I was struggling with resizing the BNC-20Rs. After checking my documentation, the strap-on cones should be 2.3" from the shoulders, all other dimensions on the strap-ons are correct.

Carl has agreed to make the correct size nose cones and they are listed on the Semroc website as BNC-20SU to match the Semroc BNC-60SU Soyuz nose cone that fits our R-7 build! Hooray!

So go order 4 BNC-20SU and a BNC-60SU .

Thanks Carl!

[MarkB.]

OK guys,

I got the new strap-on cones from Semroc and they look absolutely perfect. I cut out the original nose cones and replaced them with the new ones. I'll post a picture today.

Next, a heads up. I noted in a earlier post some problems with the length of the strap-ons. Well, after crunching numbers, blowing-up three views and measuring the now-almost-completed rocket, two critical changes and one minor change from the original Alway plan need to be made:

1) the BT-20 core of the strap-ons needs to be changed to 9.5 inches long; and

2) the central length of the paper shroud of the strap-on needs to 7.0 inches long; if you happen to have the original Peter Alway plan, his shrouds are 6 7/8 which is close enough, provided your core BT-20 is long enough;

3) because the new Semroc strap-on nose cones are very accurately shaped, the thickness of the mounting strip can be reduced or eliminated.


I'm going to go ahead and start a second R-7 with the changes above so I can show-case Carl's Soyuz nose cone and the wonderful strap-on nose cones as a thank-you.

[jetlag]

pikturs, pleese! :)

[blackshire]

Fotos, comrade!

[MarkB.]

I'm thrilled anybody's reading this! As you requested, pictures:

Picture 1 is the completed central core (which by the way, is pretty darn scale according to my drawings and measurements) with the strap-ons behind and the shrouds for the second R-7 behnd that. The right-most strap-on has my original nose cone that I sanded from a BNC-20R on it and the other three have the new Semroc BNC-20SU cone.

Picture 2 shows a strap-on with the new cone and a one with the old cone and one with the old cone taken off. Note the thickness of the balsa mounting strips.

Tonight: Sanding Sealer

Tomorrow: I hope sand down the mounting strips, add the fins and prime the strap-ons after I mask off the mounting strips.

This weekend: add some paper details to the core and mask and prime it.

[jamjammer53150]

Hey most of us weenies will read any build thread , tha way we feel like we are a part of it

[PaulK]

I'm thrilled anybody's reading this! Quietly, but keenly, watching this thread. Keep up the good work, and keep posting your progress!

[MarkB.]

Thanks guys, I do appreciate the encouragement.

Here's the next set:

Picture 1 shows the fins which I cut out of 1/16 ply and sanded the leading edge. I cut an extra set for the second prototype. I must admit this is my first through-the-wall fin. I cut a slit for the fin opposite the now-much-thinner balsa mounting strip. I did not glue on the fins just yet.

Picture 2 shows a number of things:

1) it shows the strap-ons with their filled and sealed nose cones and their new fins;

2) the little arrowhead shaped balsa pieces are the vernier covers that are glued onto the central core; I pieced these together out of strip balsa but some 1" sections of 1/2 x 3/16 would be better; There is a short section of BT-55 tube with sand paper wrapped around it; before I shaped the exterior, I sanded the underside of the vernier covers to conform with the BT-55 by running the balsa back and forth (in the direction of flight) until the underside was concave.

3) my favor trick for a scale build: full size plans. In this case, I blew up one of Pete Alway's Vostok drawings to match my core diameter. This creates full size templates for vernier covers, conduits and little details soon-to-be-cutout of bond paper or balsa. I work for my company's CFO. If I bring my own 11 x 17 paper, I can use the copier at lunch so I love blowing the plans up.

[Bill]

Thanks guys, I do appreciate the encouragement.



Keep up the good work. I am accumulating the parts for mine. I really want the boosters to drop off, so that is going to take some serious prototyping.


Bill

[Bill]

If you want to detail the Vostok spacecraft, a ping pong ball at 40mm is the right size to depict the reentry module peeking out from the hole in the fairing.


Bill

[MarkB.]

Lest you think I've become so wrapped up in the Saturn rebuild, I've forgotten about the R-7, here's where we are:

The core is complete and ready for primer on the lower half (huh? trust me you'll see why later this week) The picture shows the conduit and the standoff/launch lug. The blue stripes are masking tape over the areas where the strap-ons will be glued. The strap-ons also have a similar blue stripe. The sticks on the bottom are a bad representation of the strap-on tie-downs. On the second prototype, I'll do a better, cleaner job out of 1/12 dowels.

[MarkB.]

Comrades,

Real progress! I primed the strap-ons and the lower section of the central core with Duplicolor. As I was test fitting the strap-ons, I realized that there was going to be no way to paint the lower ends of the core after the strap-ons were glued on. So I sprayed silver below the strap-on tiedowns and some Testors Euro 1 for a few inches above that. I also sprayed around the launch lug stand-off. The tiedowns were slightly over-length. I sanded an angle into the ends of the tiedowns until the mounting strips on the strap-ons were flush with the core.

Then the moment of truth, gluing on the strap-ons. I used Golfsmith long-set black epoxy on the mounting strips and on the ends of the tiedowns. I glued them on in two sessions gluing opposite sides on and rubber-banding them in place. Recall that the nose cones are not yet glued in and I removed them and pined the ends of the strap-ons in place.

After the epoxy set, I removed the pins and the rubber bands. Yahoo! I have an R-7!

Which is not to say mistakes were not made. I had not glued in the small fins anticipating that there might be a problem when the final gluing came and sure enough, one of the fins needed repositioning. I've now glued on the fins. The epoxy was probably a mistake as well, as this thing is starting to get heavy. Bill suggested a ping-pong ball for the Vostok capsule; I'm thinking I may need a golf ball for ballast. If I had to do it all over again, I'd probably spray everything the final color coat on all pieces before final assembly. I'd also leave off the core vernier covers to save a little weight. But hey, that's what the build thread is for -- you get to learn from my mistakes.

What's left? I'm going to add some cardstock details to the attachment areas of the strap-on nose cones and some small conduits. I still need to add a motor mount. Last will be to spray the whole thing Euro 1.

Finally, when this is done I'm going to write an assembly sequence and the definitive parts list. There are some little tricks I've noticed along the way that would make assembly easier. I am going to build a second R-7 using some of these tricks.

But first, I'll do a build thread for Vostok and Soyuz capsules with their all-important lattice bases. I'm shooting to have your April 12th rocket ready by New Year's.

[MarkB.]

Finally, a nice day for painting . . . .

Picture 1 shows the now completely assembled (and glued) R-7 on the paint stick outside getting primed. In case you missed it, the S-IVB is from a Centuri Saturn 1B I'm rebuilding in another thread.

Picture 2 shows a close up of some of my cardstock details. I can't thank Sandman enough for introducing me to this technique. It never ceases to amaze me how cool these paper details look under a coat of paint. The "butterfly" strap-on hold downs and the conduit above them are cardstock. The clamps are little pieces of 1/16 square sanded and sealed. The conduits are a little too wide. I'll narrow them on the next one. . . .

The next post should be the last of the R-7 build thread. I hope to have a comprehensive parts list and an assembly sequence. I'm going to do a separate thread for building Vostok and Soyuz capsules, including the open framework interstage. I already have all of the parts except to the dowels.

Only 127 days 'till the 50th Anniversary.

[MarkB.]

Comrades:

We're down to 105 days until April 12th!

Picture 1 shows the now complete R-7 8K72 Vostok s/n 10316 with the balsa nose cone base in place.

Picture 2, which I'm also going to post in the capsule build, shows the various lattice rings and the core shroud adapter ring and the strap-on "butterfly" holddown pattern.

I have revised the parts list in the first post of the thread so you can refer to that for your parts. I'm going to cover a few little time and effort saving pointers regarding build sequence:

1) Round-up, cut out and prepare all of the parts prior to beginning;

2) mark two lines 180 degrees apart on the BT-60 portion of the strap-on boosters - one is for the fin, the other is for the center of the mounting strip. This will keep you from messing up the way I did.

3) In marking the core, in addition to the four lines for the strap-ons, you'll need two more lines: one for the distinctive long conduit that runs the length of the core and the other for the launch lug; I placed these two lines opposite each other. The core shroud joint lines were lined up with the conduit mark and covered by the balsa conduit;

4) Omit the vernier covers at the bottom of the core section unless you're super detailing; this thing's very tail heavy as built. The final balance point is just below the tips of the strap-on nose cones.

5) completely paint everything before final assembly - there's just no way to paint everything once its assembled.

6) In lieu of the vernier covers mentioned above, cut a 1.125" strip of the Chrome Trim MonoKote and wrap it around the very bottom of your core tube after you paint it. unless you install engine mounts for cluster power, you should also cover the bottom of the strap-ons with this material -- I'll provide a template for cutting the heatshield for the strap-ons; all R-7s after Sputnik had these shiny heatshields.

7) If you are building an early '60s rocket, I couldn't find evidence that the lower 2/3s portions of the strap-ons were painted Russian Marker Red (sorta like International Orange) as they are on modern Soyuz launches.

8) My personal opinion is that the European Grey is a little on the dark side, I might go with Gunship Grey on the Soyuz I'm building. And if you wanted to paint it overall O.D. or Testors Russian Green, I think that'd be OK too.

Finally, while this is a sport scaler, it absolutely nails the look of the original from a foot or two away. I hope at least some of you build one before April. I'll be glad to answer questions, provide measurements, templates or advice any time. In all the time I've been building rockets, I have never felt the sense of accomplishment I did when I took the tape and rubber bands off the final assembly.

Now all we need is a capsule . . . .

[Bill]

Picture 1 shows the now complete R-7 8K72 Vostok s/n 10316 with the balsa nose cone base in place.




Hmm...looks almost olive drabbish in that picture. No wonder there is so much confusion on what the actual color is.


Bill