DoublSShot Boiler Plate Static sugar motor Test Sept 10, 2011 video cams 1 & 5

First test of the 160+ pound 12-6" STAR grain sugar propellant DoubleSShot rocket motor.

Category:

Science & Technology

Tags:

• SS2S
• Sugar Shot to Space
• Sugar Shot
• DoubleSShot
• suagr motor
• sugar rocket
• R-candy
• sorbitol
• KNO3
• rocket motor
• solid rocket
• solid rocket motor

[LIONMAN11111]

Why you are using a star grain geometry and not simply a core grain geometry ? the thrust curve profile are very similar to each other, but the star grain geometry is much more difficult to made...

Also have you ever though the possibility of the negative erosive burning ?

[mojaverockets]

@LIONMAN11111 We will be using a light weight composite motor casing for the flight and the 'Bates' core grain heat from between the grains weakens the casing. By using a full length neutral burning STAR core in a long single grain we eliminate those places.

[donperry1]

I know you guy's are pro-amateurs but here are my thoughts.

I'm wondering if the casing swelled under pressure, separating the grain inhibitors in the process, creating more burn surface area.

I'm guessing you are running the KN ratios at the limit :D

Hope you find the cause of the "anomaly"

[mojaverockets]

@donperry1 That would be a very good possibility if we case bonded the propellant. We actually cast it in casting tubes that 'free float' in the casing allowing the combustion gases to pressurize both the inside and outside of the propellant to eliminate swelling/cracking/separating of the propellant. Thanks for the thought.

[david1513]

@mojaverockets can i ask you another guestion? what size core burn are you useing, give me inches if you can ok? i beleave your caseing is ok, your core might be to large building pressure far to fast. plus the longer the motor and core the more power it develops the biger the core the faster the pressure, fat rocket motors have less power then a long motor has, fat motors only give more run time,

[david1513]

@seleneteam i grind my kno3 fine like face powder with a blinder not a coffee grinder like most do, when i cook it it always desolves frist then my confection sugar desolves next, i use only domenos pure cain sugar ive only had two catos in 55 years, im 62 now, the two cato's was caused by a bad cardboard linner, wrong cardboard used for linner...!

[seleneteam]

@david1513 Sorbitol dissolves in pure methanol above 50 degrees very good, but try to dissolve the according amount of KNO3 in methanol!!

[mojaverockets]

@david1513 Lower density means less propellant in the rocket and if there was a lot of alcohol that evaporates it could cause many voids that would cause the propellant to burn faster and maybe lead to overpressurization and you see the results in our video of what overpressurization can lead to.

[david1513]

@mojaverockets ok is that good or bad sounds bad?