WonderBoy Posted February 23, 2011 Posted February 23, 2011 I've been testing some 1lb nozzle less spindles recently. This particular motor took an interesting path. http://www.youtube.com/watch?v=f77V4WadYRY It had a bottled water weighing a pound strapping taped on top, plus a little safety powder to burst the bottle. I know that this motor can lift this pretty easily, so my theory is that the upward thrust made the bottle crumple a little and lean over, shifting the CG significantly enough to cause the rocket to veer off course like it did.What do you think happened?
nater Posted February 23, 2011 Posted February 23, 2011 Was the water in a vacuum or was it able to move around inside the container?
dagabu Posted February 23, 2011 Posted February 23, 2011 IMHO-The stick broke, I have had that happen several times before testing each stick by hand, bending it to one side and then the other to see if it would snap. Heavy headings are more prone to this due to the weight that sits on the stick side. If it were just the motor the stick may not have broken.
Blackthumb Posted February 23, 2011 Posted February 23, 2011 If you launched from the ground.....weight on the stick....could be the problem. I launch all my heavier rockets, especially those with headers, from an angle iron or go to a carpet store and get a long core to use as a launch tube....will alleviate the problem. Keep posted with results... I split the heavens with the thunder of man…I vanquish the night with the stars of my hand…BlackthumbBook 75 Chapter 15 Verse 10
WonderBoy Posted February 24, 2011 Author Posted February 24, 2011 (edited) The water was able to move around, I just refilled one of these to weigh exactly 1 pound:http://www.triplepundit.com/wordpress/wp-content/uploads/2009/11/bottled-water.jpgThat, plus the flimsyness of the bottle was what led me to my conclusion. I hadn't thought much about the stick breaking because I've never broken one before. It was bamboo, and I usually do check the sticks strength before using it, but I may have forgotten to this particular time. Unfortunately the launch site is covered in waist-chest high weeds right now, so I was unable to recover the rocket. And I launch from ~3'long by 3/4" pvc pipe mounted to a saw horse. P.S. How do I make pictures smaller? Edited February 24, 2011 by WonderBoy
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