Doggonewild
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Hmm, that is not how I pictured you would look
Hmm, that is not how I pictured you would look
Here's a trick if you want a "quick-n-easy" fin placement guide without having to print and glue up and cut out templates...
Take a sheet of printer paper and wrap it around the body tube tightly, and make a mark where it overlaps the end of the paper sheet, with an arrow pointing back toward the overlapped edge (reference so you measure to the right end from then on). Remove the sheet of paper and lay it flat, measure from the overlapped edge to the mark. Measure the other side of the sheet and duplicate the mark on the opposite edge of the paper, and connect the marks with a ruler. This is the tube circumference.
Next, select a number that is an easy multiple of the number of fins you plan to use, that is also greater than the tube circumference. Say the tube circumference is 8.75 inches, and you want to use 4 fins. 10 would be a good choice (because 2.5x4=10). Line the ruler up with the corner of the paper, pivot the other end until the "10" mark lines up with the circumference line across the paper you made earlier, forming a long slender 'triangle' across the paper. Make the marks at the selected "multiple number" you chose earlier (2.5 in our example) so you'd put marks at 2.5, 5, and 7.5 inches. Flip the paper to the opposite edge and repeat. Connect the fin placement lines across the paper and extend them to the edge of the paper-- this ensures they're all square to each other and the paper edge. Wrap the sheet around the rocket again, tape it with a bit of tape, and transfer the fin placement lines to the tube.
Voila you're done! Quick and easy.
Course, your templates are nice too...
Later! OL JR
That's quite a different way to make a fin placement guide. Thanks for letting me know about it. I'll give it a try sometime in the future.
Very very nice...
Thank you for saying so. Besides me, now I know at least two people like the ASM.
Well....now you three
Paul
Very nice... good job! Looking forward to seeing her in paint...
Later! OL JR
Interesting.
A+ for your presentation !
I don`t remember ,what is the finished length of the rocket ?
Paul T
34" sounds like a good size.Me thinks I gots to make me one of those......if you son`t mind
Paul
That's an interesting baffle set-up... is/does the inner tube have holes drilled? Or is the idea to allow the gases to pass thru the outside tube/chamber?
Here's how the baffle works. ... The pressure wave from the ejection charge has to move up the motor tube. .... The path the pressure wave has to take is already full of cool air. As the pressure wave travels up the motor tube it's forcing the cool air up the motor tube, through the baffle and pushing out the parachute. The parachute is deployed by cool air and will be long gone before any hot gas from the ejection charge reaches the parachute compartment. Pretty cool!
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