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Estes astro sprite

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ScrapDaddy

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I have had a fasination with the sprite since I was a kid but I lost it in a CATO a year ago so I was wondering If anyone has one or has any leads please email idontknow12804@hotmail.com
 

Slickwilly

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Try Jim Z's rocket plans or Ye Olde plans for plans to scratch build one.
 

WillMarchant

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I believe that fliskits.com is selling one. And Hawks Hobby was selling a very cool Mega-Sprite.
 

ScrapDaddy

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It has to fly on standard 18mm motors and ust utilize tumble recovery
 

BEC

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The Fliskits Tumbleweed is a downscale for 13mm motors.

Get the plans from JimZ (http://www.spacemodeling.org/JimZ/estes/k-15.pdf). Then you can get all the parts except the guaze to hold the engine holder on from Semroc (collected here: http://www.semroc.com/Store/scripts/ClassicParts.asp?ID=16). This includes laser cut fins. While you're at Semroc, get some of these short engine casings (http://www.semroc.com/Store/scripts/prodView.asp?idproduct=311) so you can stick a 13mm motor inside to simulate the Sprite's original 18mm diameter 1.75 inch long motors.

Based on experience from building and flying my own Sprite clone you'll probably want to cut another vent hole or two in the body tube similar to the one that is there because ejection charges on Estes engines are rather stronger than "back in the day" and the WILL blow out past the end of the motor hook instead of just sliding back like they're supposed to.
 
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MarkII

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The Fliskits Tumbleweed is a downscale for 13mm motors.
The Tumble Weed is obviously inspired by the Astron Sprite, but it is not an exact downscale. The nose cone and body tube of the TW are both shorter in relation to the overall size of the rocket than the same components are in the Sprite. The motor also has a much tighter fit in the body tube of the Tumble Weed than was the case with the motors in the Sprite. I did a fair amount of sanding of the inside of my TW's body tube in order to loosen the fit somewhat, based on the hypothesis that a tight fit translates into a greater build-up of pressure when the ejection charge fires. My thinking was that this would cause the motor to be pushed backwards with so much force that the motor hook could not retain it. If the motor was allowed to move more easily, the ejection gas pressure would be vented more quickly and consequently the force acting on the motor would not be as great. The ejection charge in 13mm motors produces much more force than is necessary to move them rearward to the recovery position in the Tumble Weed.

The Astron Sprite was the second model rocket that I ever built and it was my favorite rocket in the fleet that I had in my youth. I had the somewhat dubious fortune of ordering my FlisKits Tumble Weed right before Jim switched to using laser-cut fins in the kit. Cutting out the template, using it to trace out the patterns on balsa and then cutting out and shaping those microscopic fin tip caps was a character-building experience... :rolleyes: After several frustrating attempts to execute the shape in soft balsa, I ended up making them out of sheet styrene. I was able to make much more precise cuts in that material, and fabricating those caps absolutely required a high degree of precision. Also, the template was simply too small to hold in place with my fingers; it was even too small to hold in place with a pin. I ended up using the small cardstock sheet that I had cut the template out of, employing the fin cap-shaped hole that was left in it as a stencil to trace the pattern onto the styrene.

MarkII
 
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