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LeeR
03-30-2016, 06:41 PM
I was recently looking at information on plastic model conversion for flight (PMC). I ran across a build thread on the old MPC Vostok plastic model. I've had one for maybe 25 years, but never started it.

FYI:
The build thread I found is documented in Chris Michielssen's Model Rocket Building blog. A link in Rocket Reviews lists all the individual posts:
http://www.rocket reviews.com/model-rocket-building-mpc-vostok-build-part-1-parts.html

I pulled my MPC Vostok out of storage, I had thought about building this kit. Finding an article on it convinced me to start. A childhood friend and fellow model rocket enthusiast had one of these when it was first released around 1969-70. I absolutely loved that model. I recall that he had flown it successfully. Not everyone has had the same experience. This kit actually had the parts needed for conversion for flying, and the box art highlights the flying version. I never saw one in the hobby shop back when my friend found his, so when I found it advertised via mail order in the early 90s, I bought it. (and I paid a fortune for what was then kind of a collector's item-- $79.95!)

Here is a picture of the box and its contents. The supplied conversion parts are a motor tube, a slightly larger tube that it slides into, and a motor block and hook. A parachute and piece of fiberglass wadding are included, as are things like nose weight, and enlarged flight fins. The kit also has molded launch lugs. You can see the difference in size between the display version fins and the flight fins, at the left of the picture.

http://i265.photobucket.com/albums/ii220/hobbes_pics/Vostok/th_85D6C6F9-D7AC-43BB-B64C-13E53F8CC0D5_zpsvx6fv9lb.jpg (http://s265.photobucket.com/user/hobbes_pics/media/Vostok/85D6C6F9-D7AC-43BB-B64C-13E53F8CC0D5_zpsvx6fv9lb.jpg.html)

mojo1986
03-30-2016, 08:20 PM
Lee, did MPC re-issue that kit? I see one on Ebay right now.................

http://www.ebay.com/itm/Vintage-MPC-Russian-Vostok-RD-107-Build-To-Fly-or-Display-Model-Rocket-Kit-NEW-/131766081714?hash=item1eadded8b2:g:~XMAAOSwa-dWtS80

the mole
03-30-2016, 08:50 PM
This kit has been re-released with all the flying plastic parts.
http://www.hobbylinc.com/mpc-vostok-rocket-plastic-model-space-craft-1:100-scale-792

LeeR
03-30-2016, 09:40 PM
Lee, did MPC re-issue that kit? I see one on Ebay right now.................

http://www.ebay.com/itm/Vintage-MPC-Russian-Vostok-RD-107-Build-To-Fly-or-Display-Model-Rocket-Kit-NEW-/131766081714?hash=item1eadded8b2:g:~XMAAOSwa-dWtS80

Yes, and I just ordered one for something like $28.88 (plus $5 shipping). They left out the cardboard tubes and parachute and other "add-ons". And as "the mole" mentions, the plastic parts needed for flight are included. The plastic flight items are pretty much the enlarged fins. But a less detailed plastic aft end piece (nozzles) is included and does have a launch lug. The upper lug can be cut off if you just want a display model.

LeeR
03-30-2016, 09:53 PM
My first step is the assembly of the four booster strap-ons. Reviewers complain about fit. After building rockets, you are accustomed to gaps here and there! I have not built a plastic model in a long time, so I found the fit to be pretty decent. With the booster halves pressed together, the fit at top and bottom is pretty good, with slight gap in the center. Squeezing them closed the gap.

The last time I built a plastic model, I mostly used tube cement. I had a bottle of Model Masters liquid cement, but chose to use Plastruct Plastic Weld, which I bought a couple of weeks ago in anticipation of building the new Estes Little Joe II.

While holding the halves together, I used a tiny paint brush to paint a line of the solvent along the seam. I only used the bottle cap brush to paint the seams on the inside, at the bottom of the booster. I then wrapped rubber bands around the booster and allowed them to dry. This first booster has a pretty noticeable seam since I probably over brushed the seam. The remaining boosters look better. A bit of fine sanding or scraping before painting will fix the blemishes.

NOTE: The wooden block in the picture is my bottle stand. For small, narrow bottles, I make a holder so I do not tip them over. I also drill holes in it for things like brushes. I've got a large set of Forstner bits so I can make them fit pretty closely.

http://i265.photobucket.com/albums/ii220/hobbes_pics/Vostok/th_18971A10-FFBE-4329-8BCF-994878D2D204_zpswxnizltp.jpg (http://s265.photobucket.com/user/hobbes_pics/media/Vostok/18971A10-FFBE-4329-8BCF-994878D2D204_zpswxnizltp.jpg.html)

Daddyisabar
03-31-2016, 03:29 PM
Green Squadron putty is your friend!

LeeR
03-31-2016, 08:27 PM
Green Squadron putty is your friend!
I may luck out and not require a bit of it. I was able to apply enough pressure to close the long, relatively even gaps on the 4 boosters. The main tube, which was the core motor on the rocket, had a much better fit. I lightly sanded on a flat surface to close the minor gap some, and then glued them. Oddly, this part has no male and female alignment pins, like the four boosters. Holding them registered evenly while the solvent welds dried was a bit difficult. Here is a picture of the central tube, with some rubber bands for insurance while the styrene re-solidified. I used a lot of Plastic Weld on this assembly to guarantee that it is now effectively one piece of plastic!

http://i265.photobucket.com/albums/ii220/hobbes_pics/Vostok/th_8867E647-5B33-49A2-A2A7-001818D02764_zpskeob6slw.jpg (http://s265.photobucket.com/user/hobbes_pics/media/Vostok/8867E647-5B33-49A2-A2A7-001818D02764_zpskeob6slw.jpg.html)

Brent
04-01-2016, 04:22 PM
Here is the one I converted. I think I used 20mm tubing from Balsa Machining to center the 18mm motor mount. The tube fit perfect inside the plastic body. I have been working on converting the MPC Titan III but have been getting frustrated with the paint not sticking between masking on the 2 SRBs.

LeeR
04-01-2016, 10:11 PM
The new MPC Vostok kit I ordered right after starting this build arrived today. Not sure if I'll save it as a backup for flying, or consider it for a display model. I unwrapped it since I was curious if all the plastic parts needed for flight were present. I was surprised that some of the pieces were there, like the second amotor nozzle plate, which has the molded launch lug on it.

I found the Euro Gray paint recommended in a plastic model review I saw recently. It is Model Masters 1988, if anyone is so inclined to build one and paint it in gray. Old references claim the Vostok was olive drab, but later described as medium gray. Apparently old photos gave the rocket a greenish hue. I think this is also true of the N-1.

The old kit was shown in white, with red markings. This was how the Russians finished the rocket they displayed at the 1967 Paris Air Show. Actual Vostok rockets were all gray, with no markings. The white on the central area of the boosters is condensation from cryogenic fuel in the tanks. I'll likely leave the white off on mine, at least for now. I struggle with detailing too much until I fly it. It will be flown on an Aerotech 18mm RMS using a D13 reload. Stories of flying these on C6-3s scare me!

LeeR
04-01-2016, 10:20 PM
Here is the one I converted. I think I used 20mm tubing from Balsa Machining to center the 18mm motor mount. The tube fit perfect inside the plastic body. I have been working on converting the MPC Titan III but have been getting frustrated with the paint not sticking between masking on the 2 SRBs.

Brent, have you flown yours yet?

Brent
04-01-2016, 10:31 PM
Brent, have you flown yours yet?
No it has been setting in my display cabinet. I have a few D21s to fly it on but haven't got around to it. I usually just fly what low power is in the trailer. If I crash something I put something else in.

LeeR
04-03-2016, 06:41 PM
Building the model rocket (paper/cardboard) part of the kit:

(Note: I received my new MPC Vostok kit, partially shown in the pictures. It has everything the old kit had, minus the model rocket parts needed for flight conversion. But the few plastic items needed for flight conversion, like bigger fins, are still included, meaning it will still be pretty easy to do the PMC.)

The paper body tube for the Vostok is roughly 20 mm in diameter. An 18 mm motor tube has an engine block installed at the top, and a hook is added for motor retention. This was a very tight fit into the 20 mm body tube, so a slit was made in it to allow easier installation of the motor tube. The motor tube is pushed about 1/2 way in, a glue ring is added around the motor tube, and then it is pushed in until 1/4" hangs out the end of the body tube. The slit receives a bit of white glue to hold it together, and allowed to dry.

http://i265.photobucket.com/albums/ii220/hobbes_pics/Vostok/th_20E1CBD6-5D21-4AEE-B329-506C98458B79_zpshynbclsp.jpg (http://s265.photobucket.com/user/hobbes_pics/media/Vostok/20E1CBD6-5D21-4AEE-B329-506C98458B79_zpshynbclsp.jpg.html)


Next, a shock cord anchor is installed on the outside of the tube, so that parachute packing is easier. I replaced the pre-made anchor, which had larger holes punched in it, for the supplied elastic. I used a piece of notecard, with smaller holes punched for the Kevlar anchor cord (not supplied, I added this). This rocket is heavy, and it will be a challenge to pack the supplied 20 inch chute into the 20 mm body tube. The top of of tube got a small notch cut in it to allow the Kevlar anchor cord to pass back into the tube for recovery gear packing. The shock cord anchor and notch will not show when the 20 mm body tube is installed into the core booster plastic tube. The top part of the booster has a plastic transition piece added to the top of the plastic tube. You can see the Kevlar cord pass thru the notch, and into the body tube, in the 2nd picture below.

http://i265.photobucket.com/albums/ii220/hobbes_pics/Vostok/th_3ADD06D6-3C1E-4CD2-BA92-AD4CAEDAA9A5_zps6vmr18rh.jpg (http://s265.photobucket.com/user/hobbes_pics/media/Vostok/3ADD06D6-3C1E-4CD2-BA92-AD4CAEDAA9A5_zps6vmr18rh.jpg.html)

http://i265.photobucket.com/albums/ii220/hobbes_pics/Vostok/th_87BA9698-F22C-4C0B-BC59-EBACB15FE7C4_zpsakrf97f1.jpg (http://s265.photobucket.com/user/hobbes_pics/media/Vostok/87BA9698-F22C-4C0B-BC59-EBACB15FE7C4_zpsakrf97f1.jpg.html)

The next picture shows the engine tube sticking out of the end of the plastic booster motor tube. The aft nozzle assembly will be glued onto the end of the tube, after the 4 strap-on boosters are added.

http://i265.photobucket.com/albums/ii220/hobbes_pics/Vostok/th_BB14EA76-61A7-4974-82A1-AA051C8BC81B_zpsvenewuvc.jpg (http://s265.photobucket.com/user/hobbes_pics/media/Vostok/BB14EA76-61A7-4974-82A1-AA051C8BC81B_zpsvenewuvc.jpg.html)

In the picture below, the nozzle is test fit to the end of the rocket, to make sure everything lines up. On the real Vostok, the aft end and nozzles are bare metal, so these will be painted silver, before being glued onto the core motor tube, which will be medium gray. The strap-on boosters will also get painted medium gray, with asmall areas at the base painted silver to represent bare metal.

http://i265.photobucket.com/albums/ii220/hobbes_pics/Vostok/th_EF5F1A77-EBC7-4E26-8DD6-630052296968_zpstc1jbmqb.jpg (http://s265.photobucket.com/user/hobbes_pics/media/Vostok/EF5F1A77-EBC7-4E26-8DD6-630052296968_zpstc1jbmqb.jpg.html)

The capsule construction and strap-on booster construction and painting will be covered next.

the mole
10-13-2016, 06:10 PM
LeeR......Have you did any work lately on Vostok? Have you had a chance to do any flight test?

LeeR
10-13-2016, 06:25 PM
I haven't done anything rocketry-related in months! We started s big house remodeling project, which could go on another month or so. Hopefully some time this winter to do some work on it.

Sadly, looks like I missed all chances to fly anything over the summer, although there have been some cancelled launches due to dryness and fire bans.

Thanks for the reminder. I bought paint for the Vostok and really want to get it finished!