Thinking about making a Sputnik

[Kelley]

I just got back into rockets, over here in Germany. I got to thinking about rockets I wanted to build in my childhood. I have been poking around the internet looking at the old Estes plan for the Sputnik-too. Also seen someone made a kit. I got to thinking I could scrounge up some 3 mm dowels (got 'em), a 70 mm Styrofoam ball, (on the way) and some 13mm tubes.

Now here is where I need to talk to you guys with slide rules and rocket simulator programs and whatnot. Instead of just poking and gluing 4 sticks in the back, do you think it would be feasible to make some paper (or balsa) fairings, and mount the sticks on the outside of the ball, slightly forward of the middle line? Kind of make it semi semi scale and not just sticks stuck in a ball?

I would not have a clue on how to crunch the numbers on the CG/CP, and how unstable it would be making this thing at least the closer to the look of the original.
Thanks!

 

[Kelley]

Oh I seen where I can get 2mm sticks online. It would look even snazzier!

 

[hcmbanjo]

I think as long as your engine is far forward and the sticks are long enough, it should fly fine.
My company, Odd'l Rockets makes the kit:
https://oddlrockets.blogspot.com/p/kits-page-2.html

The antenna placement on the Moonnik-1 is closer to the Sputnik.
Just food for thought - This one uses 18mm engines and side ejects a parachute:
https://www.spacemodeling.org/jimz/eirp_14.htm

 

[rstaff3]

I have seen several through the years including a really big HPR version that used PVC pipes for the legs. It seems you could come up with a near scale version based on a styrofoam ball pretty easily. I would mount them on the outside and accept the chance that they could pop on landing. Should be easy to fix up.

On my MicroMaxx Sputnik-like thing, I just slapped it together and flew it. On a 13mm with a styrofoam ball, I'd say that is not unreasonable. On my stick-stabilized rocket (shown below), I put it in RockSim and swung it to make sure. On a Sputnik, I have less faith in either method.

 

[Kelley]

I think as long as your engine is far forward and the sticks are long enough, it should fly fine.
My company, Odd'l Rockets makes the kit:
https://oddlrockets.blogspot.com/p/kits-page-2.html

Thanks! I read your blog on making these. I feel your pain and do not want to take away from your kits! I just want to see what I can come up with with playing with it. reading what a pain it is to find undamaged balls and cutting them, I ordered 10.

 

[Kelley]

If my memory serves me right, there was a tiny rocket that I want to say was from Century that used minimotors and it was pretty much an engine mount with a nose cone and some paper fairings holding sticks. I remember something that also had sticks and tiny paper fins on the tips. If I poke around long enough I will find it online.

 

[rstaff3]

If my memory serves me right, there was a tiny rocket that I want to say was from Century that used minimotors and it was pretty much an engine mount with a nose cone and some paper fairings holding sticks. I remember something that also had sticks and tiny paper fins on the tips. If I poke around long enough I will find it online.

https://semroc.com/Store/Scripts/RocketKits.asp?SKU=KV-72

 

[Kelley]

Oh I see there are a couple of threads here on Sputniks. I seen where someone had an ejection pod with a streamer for use with bigger motors. That was going though my head too. Ill build the mini one first and go from there. Thanks everyone for their feedback. As a born again born again rocketeer, I will say that the people in THIS hobby is way way way more open with info and are willing to share, than some other modeling hobbies I won't name.

 

[Kelley]

https://semroc.com/Store/Scripts/RocketKits.asp?SKU=KV-72[/QUOTE
Found the Century one [h=3]Centuri Satellite 62SL[/h]

 

[Kelley]

So doing some calculating and fudging numbers. Sputnik was 58cm with two antennae 240cm and two 290cm. Playing around with a scale converter and rounding things, if I use a 7 cm ball, I can get close to 1/8.25 scale. Putting in the other numbers I get 29cm and 35 cm so to make things even I will say 30cm. Angle of antennae is 70 degrees from each other. Once the balls and the smaller wood come in the mail I will take pictures. of the work in progress.

 

[Nytrunner]

Putting in the other numbers I get 29cm and 35 cm so to make things even I will say 30cm. Angle of antennae is 70 degrees from each other.

70 degrees along what orientation?

 

[GregGleason]

70 degrees along what orientation?

It may be he means along the axis of travel.

Greg

 

[Kelley]

70 degrees from each other, I guess that would make them 35 degrees from its center axis? Oh thanks for the plans, They will come in handy.

 

[K'Tesh]

Funny you should be thinking about this... I was working on a sim of the Sputnik not all that long ago. However, I couldn't source a dimensional drawing (that I could understand) to save my behind.

 

[OverTheTop]

Carbon fiber rods from a kite shop or model shop for the antenna?

 

[OverTheTop]

This flew successfully at Thunda Downunder in 2015 (J450 Black Ligntning):

 

[Kelley]

I can get 1 mm carbon fiber rods. I was thinking if they are too thin and too light they would not do the job of stabilizing. I am also looking at these 2 piece acrylic balls. Might be a smoother finish to paint, real Sputnik was kind of 2 half balls. Just have to see how paint and glue takes to it all, and if it could last though more than one landing.

 

[Forever_Metal]

love the red-eye

fm

 

[Kelley]

Monster eyeball spider robot thing from Johnny Quest would be pretty awesome. If any red blooded American kid was around building rockets in the 60s and 70s, they had to have been watching Johnny Quest.

 

[OverTheTop]

You could make the rods easily replacable then it doesn't hurt so much if you break one or two.

You might be able to blow the motor out the bottom and drag a chute out that way. Then it would land head first and be a bit easier on the legs.

 

[Micromeister]

Been flying all kinds of Sputnik type rockets for decades. Mostly using styrofoam balls as the heads and 3/16" hardwood dowels for the antenna's. I've even downscaled a couple to 1" head Micro Maxx powered. D versions do use a ejectable pod with streamer. By adding a Stiffened cheesecloth fabric a Sputnik model can easily be turned into a fine flying Ghost.

 

[dpower]

...I got to thinking I could scrounge up some 3 mm dowels (got 'em), a 70 mm Styrofoam ball, (on the way) and some 13mm tubes.

I use an 18mm mount for my 70mm Sputnik, and fly it on C6-0 motors, probably does about 250' A 13mm A motor will go about 75', you may want to consider 18mm.

 

[Kelley]

I found some real Carpenter Wood Filler somehow online over here in Germany. I want to try and see if i can smooth out the Styrofoam ball. (If it wont work then please chime in!). Still waiting for the 2mm dowls and the CWF to show up, which will be any day. I have a buddy over here that is an Ex-Sea Bee, and he is supposed to make me a measuring/cutting jig for the 70mm balls (Sea Bees can build ANYTHING). I think I might just put an 18mm mount as suggested. Can't wait to see how it would fly with a Klima D engine OH! another side note, I talked my buddy into getting some rockets. He is starting out with the Micro Maxx ones but it is a start.

 

[Incongruent]

I've read that spackling will work for filling the foam.