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!

__________________
NAR 79743
NARTrek Silver
I miss being SAM 062

Awaiting First Launch: Too numerous to count
Finishing: Zooch Saturn V; Alway/Nau BioArcas; Estes Expedition; TLP Standard
Repair/Rescue: Cherokee-D (2); Centuri Nike-Smoke; MX-774
On the Bench: 2650;
Dream Stage: 1/39.37 R-7

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.

__________________
NAR 79743
NARTrek Silver
I miss being SAM 062

Awaiting First Launch: Too numerous to count
Finishing: Zooch Saturn V; Alway/Nau BioArcas; Estes Expedition; TLP Standard
Repair/Rescue: Cherokee-D (2); Centuri Nike-Smoke; MX-774
On the Bench: 2650;
Dream Stage: 1/39.37 R-7

pikturs, pleese!

Fotos, comrade!

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

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.

Attached Thumbnails

   

__________________
NAR 79743
NARTrek Silver
I miss being SAM 062

Awaiting First Launch: Too numerous to count
Finishing: Zooch Saturn V; Alway/Nau BioArcas; Estes Expedition; TLP Standard
Repair/Rescue: Cherokee-D (2); Centuri Nike-Smoke; MX-774
On the Bench: 2650;
Dream Stage: 1/39.37 R-7

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

__________________
If it was easy , everyone would be doing it
www.jammer.com

Quietly, but keenly, watching this thread. Keep up the good work, and keep posting your progress!

__________________
Paul
If we weren't all crazy, we would go insane - Jimmy Buffett
NAR #87246 www.wooshrocketry.org

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.

Attached Thumbnails

   

__________________
NAR 79743
NARTrek Silver
I miss being SAM 062

Awaiting First Launch: Too numerous to count
Finishing: Zooch Saturn V; Alway/Nau BioArcas; Estes Expedition; TLP Standard
Repair/Rescue: Cherokee-D (2); Centuri Nike-Smoke; MX-774
On the Bench: 2650;
Dream Stage: 1/39.37 R-7

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

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