Rocketarium Aster 15

[Desert-rat82]

Has anyone here built this kit? My first gap staged kit. The booster and sustainer slip together approximately 2”. Seems like a lot to me. Would be easy to shorten. Also no instructions on a hole/holes to allow cool air to be pushed out to aid staging. Any suggestions on coupling and venting would be appreciated. Thanks,Ryan

 

[Donnager]

I haven't built that kit, but I have built two gap-staged rocketarium rockets. Both of mine worked/staged perfectly. I also made a boosted estes NikeX with the same style of porting. I can give you the venting I've allowed for, BUT....

Yours looks to have very little if any annular space between the motor tube and the airframe on the second stage. I'm not sure if basic venting works the same way on yours. Can you post up instructions?

 

[Desert-rat82]

I haven't built that kit, but I have built two gap-staged rocketarium rockets. Both of mine worked/staged perfectly. I also made a boosted estes NikeX with the same style of porting. I can give you the venting I've allowed for, BUT....

Yours looks to have very little if any annular space between the motor tube and the airframe on the second stage. I'm not sure if basic venting works the same way on yours. Can you post up instructions?

Thanks. Yes the two do mesh together pretty far. The sustainer motor actually extends to about the middle of the transition. The transition isn’t glued yet. I’m thinking about venting to sustainer motor tube under the transition and drilling holes in the centering rings to exhaust it out the bottom

 

[Donnager]

It looks like both my Daedalus and the Super chief have a pair of 3/32 holes at the top of the bottom stage. I had a smaller annular space in an Estes Nike X booster I built and that one vented fine with a pair of holes between 1/16 and 3/32.

The way these are vented is to have a gap between the booster/sustainer motor tubes, and the holes keep the booster from being "blown" off when the lower stage burns through, allowing enough heat to light the top stage before separation.

Based on your picture, I'm not sure how you'd vent things to prevent this from happening. If you have instructions, It would help. I'm trying to figure out how the top stage motor is mounted, if there's an annular gap to work with, etc....

 

[Desert-rat82]

It looks like both my Daedalus and the Super chief have a pair of 3/32 holes at the top of the bottom stage. I had a smaller annular space in an Estes Nike X booster I built and that one vented fine with a pair of holes between 1/16 and 3/32.

The way these are vented is to have a gap between the booster/sustainer motor tubes, and the holes keep the booster from being "blown" off when the lower stage burns through, allowing enough heat to light the top stage before separation.

Based on your picture, I'm not sure how you'd vent things to prevent this from happening. If you have instructions, It would help. I'm trying to figure out how the top stage motor is mounted, if there's an annular gap to work with, etc....

Thanks for the info on hole sizes. I’ll include 2 pictures. Hopefully they help. There is a little room around the sustainer motor mount. I may be able to drill holes between sustainer fins and through booster motor tube. Or under the booster transition and out through holes in the centering rings