RockSim Ejection Baffle

[RocketNewb]

Wondering if anyone has created an Ejection Baffle sub-assembly in RockSim they would be willing to share, or can give me some tips on creating one.

I have a Dynastar Stonebreaker I'd like to put a Sunward Ejection Baffle (BT-70) in, but I'm not sure what to use for components to build one in RockSim. I believe I need to do this to determine if I need to add weight to the nose to compensate for the weight of the baffle.

Thanks for any assistance!

 

[SteveF]

i would just use a coupler & two bulkheads - override the weight of the bulkheads to get closer - I dont think it matters to the sim that the model is "plugged" as long as your masses are in the correct places

 

[gpoehlein]

i would just use a coupler & two bulkheads - override the weight of the bulkheads to get closer - I dont think it matters to the sim that the model is "plugged" as long as your masses are in the correct places

It doesn't matter if the bulkheads are solid - all Rocsim is looking for is a recovery system of some kind. Speaking of which, it doesn't like nose blow or featherweight recovery at all. To get around that, add a .01" x .01" streamer, with a thickness of .0001". The weight will show up as virtually nothing, but will satisfy Rocsim's need for a recovery system.

The problem with generic baffles is that there are so many different BT sizes, styles and bulkhead thicknesses and materials to consider.

 

[RocketNewb]

Thanks for the replies.

I went into RockSim to add the components but it's a bit overwhelming trying to figure out what to pick for the material for the bulkheads and to figure out the weight of each component. As a result, I think I'm just going to install the baffle forward of the CG then do the "swing test" to check for stability. Then, if I need to add weight to the nose, I'll do so until the rocket is stable.

Does that sound like an appropriate approach?

Thanks again.

 

[KHamel]

Thanks for the replies.

I went into RockSim to add the components but it's a bit overwhelming trying to figure out what to pick for the material for the bulkheads and to figure out the weight of each component. As a result, I think I'm just going to install the baffle forward of the CG then do the "swing test" to check for stability. Then, if I need to add weight to the nose, I'll do so until the rocket is stable.

Does that sound like an appropriate approach?

Thanks again.

If the baffle is installed forward of the CG you should be just fine, in fact that should increase the margin between the CP and CG. Make sure you leave enough room for your recovery device (chute or streamer).

 

[RocketNewb]

If the baffle is installed forward of the CG you should be just fine, in fact that should increase the margin between the CP and CG. Make sure you leave enough room for your recovery device (chute or streamer).

Excellent! Thanks!

 

[Woody's Workshop]

I had the same problem, and sent an Email to Tim at Apogee with my file. He returned it showing me how to do it so it estimates the weight unless you have the actual baffle and a scale to weigh it. I'd be glad to send you the file email upon request to show what he did for me. Just PM me.

 

[RocketNewb]

Thanks, Woody!

I sent a message from your profile but it's not showing up in my Sent box. Could you let me know if you got it or not?

Thanks again!

 

[Woody's Workshop]

Yes, I got it. Just replied to it.
Sorry, wasn't on the computer yesterday at all. In fact, my back was problematic again so I didn't even get out of bed all day except when needed.