Wednesday, October 4, 2017

Estes Curvilinear Background

When I first saw the Estes Curvilinear it reminded me of the old Sprite design.
Only 75 cents in 1969! 

It used the old Series III short engines, 18mm X 1.75" long.
The rocket was only 5.3" tall.
The tail ring was an RT-70 at .7" long.
Balsa sheet was BFS-40, 1/8" thick.

Semroc makes a BT-30 based Sprite kit using 13mm T engines.
The Tumbleweed from Fliskits also uses T engines but is BT-5 based.
This one used tumble recovery. Here's some recovery suggestions from the instructions.


In the original Estes Sprite kit, fins were cut out of 1/8" balsa, no laser cut parts here!
I remember that fin cap piece being hard to get right. The fin pattern layout didn't give much balsa if you screwed one up.






"Curvilinear". . . Where did that name come from?
I looked it up:
Curvilinear definition: "Consisting of or bounded by curved lines."
Well, it's bounded by the tail ring I guess.

I don't know if the Curvilinear design was based on the old Sprite or not. But, it sure reminded me of that little rocket.

2 comments:

  1. Don't think the Curvilinear was a Sprite based design, though they share a tail ring in common. The name implies an attempt to create a retro style sci-fi design. Almost impossible using straight cardboard body tubes. The Fliskits Tiberius comes close but it is a constant taper from the large nose cone down to the tail, not curvilinear. The only truly curvilinear rocket I've seen is the Klima Exa, which uses a vacu-formed plastic shell around standard components. Very expensive, way out of my budget. I've also seen some cardstock models that use a series of nested shrouds. More faceted, not curvilinear. If some genius can figure out a way to defy the laws of physics and geometry and come up with a true curvilinear rocket using cardboard tubes and cardstock, he would make a fortune.
    As far as Astron Sprite based designs, I would also include the Circulus series by 3D Rocketry. Uses standard parachute recovery, since I don't think a 20 oz., F powered rocket would do well with tumble recovery. Maybe just once.

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    Replies
    1. Hi BAR,
      You are probably right, but I did recall the Sprite when I saw this model. Thanks for reminding me, I didn't think of the Circulus from 3d Rocketry.
      The upscale Sprite tumbling in would be dangerous. Somebody built a huge Cyclone model, the blade on the upper part was 3 feet long. That would be like a spinning machete when it was mono-coptering in!

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