"Baby J, 29mm J500 in a 29mm case"

The Rocketry Forum

Help Support The Rocketry Forum:

mo2872

Well-Known Member
Joined
Jun 22, 2020
Messages
499
Reaction score
402
Location
NE OK
Ok you can't just tease us like this and not provide more information lol
Try here....but he must have upped it from an I90....

 

PayLoad

I don't do spirals
TRF Supporter
Joined
Aug 21, 2020
Messages
505
Reaction score
622
Location
Orefield, PA
Try here....but he must have upped it from an I90....

Same case, different grain & nozzle. My "film Crew" decided they had dates last night & could not film, doing this today, or everyone loses their iPads!
 

PayLoad

I don't do spirals
TRF Supporter
Joined
Aug 21, 2020
Messages
505
Reaction score
622
Location
Orefield, PA
Yeah, the motor itself blew out of the stand (200 feet away), leaving the grain on the ground. Poor upper bulkhead fastening which I will address.
 

3stoogesrocketry

Well-Known Member
Joined
Feb 26, 2012
Messages
1,451
Reaction score
265
What's the style of retention? Can you share your designs ( no recipes ) for both motors ? Do I see two independent fuel compositions?
 

eggplant

L3 | NAR 93664, TRA 17791
Joined
Jan 5, 2011
Messages
1,724
Reaction score
192
Yeah, the motor itself blew out of the stand (200 feet away), leaving the grain on the ground. Poor upper bulkhead fastening which I will address.
The person holding the camera is clearly well under 50' away.
 

PayLoad

I don't do spirals
TRF Supporter
Joined
Aug 21, 2020
Messages
505
Reaction score
622
Location
Orefield, PA
Retention is currently by snap ring- Looking at the motor tube, you can see where it ripped right thru it. There are multiple fuel comps per motor - I have something I want to try with the Baby J before I give up - It was a simple bulkhead failure.
 

3stoogesrocketry

Well-Known Member
Joined
Feb 26, 2012
Messages
1,451
Reaction score
265
Retention is currently by snap ring- Looking at the motor tube, you can see where it ripped right thru it. There are multiple fuel comps per motor - I have something I want to try with the Baby J before I give up - It was a simple bulkhead failure.

Simple failure at 2k+ Pc is not just a bulkhead failure . Its a design issue that open motor or burnsim will not flag. What was your Kn 350/375? Shearing a case at the snap ring grove takes serious pressure .
 

CPUTommy

Thrust cures All
Joined
Oct 26, 2011
Messages
1,136
Reaction score
157
Location
Massachusetts
Please.. DO NOT GIVE UP!!

I WANT !!!

after crashing $1,000 I layed in bed and watched Nova "RISE OF THE ROCKETS"

31:00 -34:00. Rocketry made simple..


I
 

PayLoad

I don't do spirals
TRF Supporter
Joined
Aug 21, 2020
Messages
505
Reaction score
622
Location
Orefield, PA
Hellfire Baby "J" 1600 coming up - will start new thread. 24mm J 1600
 

CalebJ

Well-Known Member
TRF Supporter
Joined
Jan 20, 2020
Messages
640
Reaction score
447
How long is the 24mm J case??
 

CalebJ

Well-Known Member
TRF Supporter
Joined
Jan 20, 2020
Messages
640
Reaction score
447
Not bad - shorter than I was expecting for sure.
 

Mach_Seven

Well-Known Member
Joined
Jan 30, 2021
Messages
182
Reaction score
153
I think I'll stick with the I90


Upper bulkhead fail - CATO
This is backyard rocketry at it's finest. A shed, a trampoline, and a motor test stand. An explosion rocks the neighborhood. Fiery propellent spews everywhere. But it's in the snow and who gives a ****. Certainly not the guy casually smoking a cigarette 20 feet away. 'Murica!!
 
Top