Estes suggests adding another 13 grams (1/2 ounce) weight to the nose. The current kit comes with 2 "butter pats" of clay for a total of about
13 grams and they are going to change that to 4 "butter pats" or 2 "cubes" for a total of just over 1 ounce of clay.
Postings on The Rocketry Forum have the c.p. location and the actual c.g. locations with and without motors.
Also - DO NOT add a ton of filler and paint since that is one of the things causing aft c.g. shift in some models.
Using a 4 foot rod will also help it build up air speed and be less affected by cross wind. The instructions say NOT to launch in wind, but you know how some folks read instructions (not).
Using a 12 foot rod will allow the motor to burn out prior to leaving the rod, which will shift the CG far enough forward to solve the stability issues....
Mine did as well. On the last flight I tried my best to 'tie' the streamer with the shock cord, hoping it would delay the opening of the streamer slightly, but even that didn't work.
I just got finished putting together my SS1 last eve with painting and finishing to follow today. First thing I did was to replace the clay with BB's epoxied into place. So now they're saying add an additional
1/2oz to the nose? Great, I was going to do that anyway to assure the Aerotech D motor I plan on putting in it wouldn't throw things off, now I have to wonder if it needs still more trim weight. They could have done better with that little cardboard stand to help with attaching/aligning the wings. A good idea that has inferior application. The stand needs to be markly wider to be effective. I started a 1.5x upscale while waiting for glues to set that should solve that problem because it'll be sorta kinda TTW. The two wings being one piece and fitting into slots cut in the body. Looks also to be a potentially good spot for electronics in a larger upscale (thinking a 6x that uses my HyperTEK!). Nice little kit though, even with the glitches.
Oh, and if it requires no wind to safely launch I guess they never intented the kit to ever fly, thus the trim weight issues never came up during R+D. I've seen only one no-wind launch day in 2 years.
Chuck
shreadvector wrote:
current kit comes with 2 "butter pats" of clay for a total of about 13 grams and they are going to change that to 4 "butter pats" or 2 "cubes" for a total of just over 1 ounce of clay.
locations with and without motors.
causing aft c.g. shift in some models.
cross wind. The instructions say NOT to launch in wind, but you know how some folks read instructions (not).
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