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Vostok finally done!

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vjp

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After taking some time off building over the holidays, I finally picked up pace again on the Vostok project, and here she is!

The core is based on Peter Alway's Vostok plans from the "Art of Scale Model Rocketry". The boosters were cardstock shrouds made to scale (I thought the BNC-20R nose cones, as specified in PA's plans, were a bit too small and I decided to go with a more scale-like set of strap-ons), and the spacecraft section was built-up completely from epoxy and cardstock shrouds, and misc. pieces of tubes (no balsa in this project at all).

She's just over 24" tall, and about 10 oz. with chutes (but no motor). Motor mount is 24mm, sized for "D"s. In addition, the booster base sections are BT-60 with BT-20 tubes in ply CR2060's, so it's possible to put 18mm motors in the strap-ons. I doubt very much I will ever do this (mostly because there's no plugged 18mm motors out there), but I <b>may</b> try flying her with A10-PT's in the strap-ons, in adapters.
 

vjp

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Here's another shot, next to my Estes Mercury Atlas, for comparison. She's about 1/2 oz. lighter than the Atlas, but much smaller, overall. Since the Atlas flys nicely on D12-3's, I am leaning towards a D12-5 for the Vostok's maiden flight.
 

rstaff3

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Vince, that looks fantastic, and I look forward to drooling over it at a launch :) Being that Sat. will be cold and it's Valentine's, I won't be at the launch. You going to try it then or wait 'til later?
 

sandman

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vjp,

Very very impressive!

I have a Das Modell kit I'd like to turn into a Soyuz launcher.

But yours is beautiful!

sandman
 

cls

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very very very nice!! and your atlas is nice too.



(... probably a lot of drag on the Vostok, I'd put a 3 second delay on it.)

now I am inspired to make a Vostok too.
 

Loki

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Originally posted by vjp
so it's possible to put 18mm motors in the strap-ons. I doubt very much I will ever do this (mostly because there's no plugged 18mm motors out there), but I <b>may</b> try flying her with A10-PT's in the strap-ons, in adapters.
Just get some B6-0s or C6-0s and pour a little epoxy in the end to make a plugged motor.
 

vjp

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Thanks for all the kind words, folks. Dick - I don't know if I'll make it to Saturday's launch either. Right now odds are looking < 50%.

I'll post a flight report and/or video when she flys.

I have also been working on the CAD drawings for my larger, 1/40 Vostok, which will have a cluster of 4 18mm MMT's. This first model is the test article, to find out where the CG should be, and to get an idea of the overall Cd, for simming the larger model(s).

Here's a photo of the tail end, FWIW. I'll probably apply chrome foil to the bottoms of the boosters, or maybe build some plug-in nozzle units for realism.
 

Quasar

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Very nice! The only thing I don't like about it is that it makes me want to build one and I already have a closetful of unbuilt kits!
 

jflis

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very sweet. that is NOT an easy model to build, even from a kit. scratch building it takes some real tallent.

very kewl :)
 

dtomko

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Vince,
Fantastic job! And a beautiful Atlas, too. I second the thought on using a 3 second delay, though. Did you use epoxy to attach the strap ons?
Drew Tomko
 

powderburner

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Very nice job on the scale model! (starts to sound like a broken record on this thread)

I would be afraid to fly such a nice model---these things look like they should be in a museum somewhere!
 

vjp

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Thanks again for all the kind comments. Drew - I didn't use epoxy, but actually yellow glue. The boosters have 1/8" wide by 1/16" thick spruce spars which were glued to them early on in the construction process. These act as spacers to keep the strap-ons 1/16" from the core. I masked the gluing surfaces on both the spacer planks and the core tube (after sanding the 'gloss' off the tube), so that when all painting and finishing was completed, I peeled off the tape to expose raw surfaces for gluing.

Still, I am concerned that the strap-ons may "twist" upon landing and overstress the glue joint, so I do plan on gluing scale-like braces between the core and the strap-ons. This should help resist torquing and greatly strengthen the assembly. I should have done this earlier, but CA should stick well enough even to the paint, for this purpose.
 

dtomko

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Vince,
I'm planning to use the spar approach with my Energia. I asked about epoxy because the strength of attachment could be an issue if you want to add motors to the strap ons.
DT
 

vjp

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Originally posted by dtomko
Vince,
I'm planning to use the spar approach with my Energia. I asked about epoxy because the strength of attachment could be an issue if you want to add motors to the strap ons.
DT
Drew -

If you use spars, the joint will not be quite as strong as a tube-to-tube glue joint, but - I think the strength would be very adequate, especially when combined with struts to prevent side-to-side flexing. The thrust is in line with the length of the glue joint too, which in shear should be very strong.

The Energia-Buran has loads of struts, between the strap-ons and the core stage, as well as between strap-on pairs themselves. This should make for a very rigid assembly. Their placement is not really obvious at first in the drawings I've seen, but they are there, and numerous (the small 1/288 kits I've seen don't include all of them).

I will let you know how the Vostok clustering goes, when I finally get a chance to fly it.
 

eugenefl

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Great job Vince! It's amazing what one can do with some paper and creativity!

Nice work...
 

graylensman

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vjp

Excellent Vostok! That thing will look beautiful heading skyward, I promise you. the smaller Alway Vostok is a good-looking bird, and it has none of the detailing that your larger version has. And I think that if you have an adequate parachute, you won't have to worry about strap-on damage at touchdown.
 

vjp

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Flight report time!

The Vostok had two very nice flights today at Middletown Park with the NARHAMS folks. Both flights were on D12-3's, which turned out to be the perfect delay. Flight weight was 362 grams (12.8 ounces) for the first launch, second may have been a few grams heavier (used lots more wadding 2nd flight).

I added a bit more nose weight last night, bringing the CG to 45mm behind the widest point on the Vostok core. This is just a little aft of the midpoint of the aft core shroud.

First flight: D12-3, in a moderate breeze - it weathercocked into the wind, the ejection was very strong, the heat just barely "tack welding" the 30" chute together, and the rear section streamered in hard. Fortunately, it impacted in snow and suffered no damage. The upper (spacecraft) section recovered on its own 12" chute perfectly.

Second flight: D12-3, in calm air. No weathercocking this time, nice and perfect straight boost. Then - KAPOW! A really "energetic" ejection, this time burning the main chute severely and again welding it together, even though I used twice as much wadding as the first launch. I have a feeling the D12-3's I used were from a "hot" batch - my Ferry Rocket from last year had the same issue. Once again, the main section streamered in hard, and landed in nearly the exact same patch of snow as before, and again I was spared any damage (except for some chipped paint near one fin, where it flexed the strap-on BT a little).

I am really happy with its flight performance, although altitude was only about 200 feet. I think there's enough of a stability margin to augment the launch with some A10-PT's, for which I've now added BT-5 motor mount tubes inside the strap-on's BT-20 tubes shown in the aft photo posted earlier. I'll try two A10-PT's in opposite strap-ons first, and then move up to four if that's successful.

I'll post a video of the launches a little bit later.
 

vjp

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O.k., video's up!

Head over to http://members.verizon.net/vpearman/
and click to download the "Vostok" zip file (lower left hand
side, under "Videos"). The ZIP contains Vostok1and2.wmv,
playable under Windows Media Player.

I missed the hard "landing" both times, as I instinctively put
the camcorder down just as it was about to streamer in. Sorry
'bout that, crash lovers. ;->
 

graylensman

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Originally posted by sandman
greylensman,

Gor here and look around.

http://www.spaceandtech.com/spacedata/elvs/soyuz_image4.shtml

sandman
Neat stuff - great ideas brewing, now... I notice though it looks like the paint scheme has changed from the classic green-and-white.

Vince: awesome video! Thanks for posting that. Now go suck down some more slurm, it'll make you feel better about your melted chutes.
 

n3tjm

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You know, if you want to enter a Vostok in a scale contest, you can put a cluster of 4 A10-PT's in all four strap-ons :D... drool....
 

vjp

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Originally posted by graylensman
Neat stuff - great ideas brewing, now... I notice though it looks like the paint scheme has changed from the classic green-and-white.

Vince: awesome video! Thanks for posting that. Now go suck down some more slurm, it'll make you feel better about your melted chutes.
Actually, the green is probably more like gray! The old Soviet film gave it an olive-drab look. I tried to mix some gray and green for mine, to make an olive drab, but it wound up way on the green side of the spectrum, and I simply wasn't about to bother repainting.

Thanks for the compliments on the video. I wish I'd have put it on "sports AE mode" Saturday (for a fast shutter), but I ded remember Sunday, which is why the video of the 3rd flight is so much crisper.
 

vjp

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Originally posted by n3tjm
You know, if you want to enter a Vostok in a scale contest, you can put a cluster of 4 A10-PT's in all four strap-ons :D... drool....
I do have MMT's for one A10-PT per strap-on, in the current Vostok.

I've given serious thought about making room for four A10-PT's in each strap-on, on the next Vostok. :D

Hmmm, (4) C6-3's, (16) A10-PT's, that works out to about $22.52 worth of motors per flight (after 5% tax).

That could get expensive...
 

vjp

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Make that $27.72 per flight!

(@ $4.95 per A10-PT 4-pack, and per C6-3 3-pack)
 

dtomko

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Vince,
Beautiful video! Those D ejections scare the crap out of me though!
Drew Tomko
 

Justin

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Those are probally my two favorite manned rockets and they both look amazing! I have a russian model of the Vostok I plan to use for my nartrek plastic model conversion level. I have been meaning to order the Nuebauer 1/100 Atlas, but it's still sold out (I don't think I'm good enough to scratch 'em yet). I took a million pics of it at Kennedy Space Center last week to add details.

What did you use for the aluminum finish on the Atlas?
 
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