Staging 18mm to 13mm

[dragon_rider10]

Anyone have any tips on how to stage with this configuration? 18mm booster to 13mm sustainer? I'm not considering any distance between the motors, but am curious if it's possible.

 

[The EGE]

If you push on it a bit, a 13mm motor will fit nicely into the top of an 18mm booster motor. It works better with 24mm -> 18mm but it works this way.

 

[MarkII]

Should be. I haven't done it myself, but I think that it's done all the time. The mini motor will even fit right into the top of the 18mm one. I don't think that you will want to push it in very far, though, because the fit is tight and it could get stuck. I'm sure that you can also gap-stage them with a tube that tapers from the diameter of the 18mm booster to the 13mm sustainer. I keep meaning to try it, but I haven't gotten around to it. Maybe next year.

I have also heard of staging 13mm to 18mm, too. 13mm booster motors are out of production and not certified, but you can find them (old stock) for sale here and there from time to time. One can hope that Estes resumes producing them again, as they indicated awhile ago.

MarkII

 

[powderburner]

dragon,

You will probably have a bit better success and consistency if you use upr stg 13mm motors that have a "large" nozzle diam

Check the difference in nozzle (I'm talking about the little orifice itself, not the entire piece of stamped clay) between A3T and A10T motors and you will see what I mean.

Not to say that you can't stage with the small nozzle diam, just that you will have better results with the larger one

 

[Chrisn]

https://www.geocities.com/rdh82000/13mmTwoStage/index.htm

 

[chrisudy]

The Estes Solar Flare uses 18mm boosters and 13mm sustainers. I haven't flown mine yet, but I assume that it just may work... ;-)

 

[foose4string]

The Estes Solar Flare uses 18mm boosters and 13mm sustainers. I haven't flown mine yet, but I assume that it just may work... ;-)

Yep, the Solar Flare does it. I have flown mine several times and it has staged successfully every flight. There is a gap between motors, maybe an inch or two, and there is a small vent hole in the booster to help with second stage ignition. The vent lets off some of the pressure so the the booster doesn't pop off too early without igniting the upper stage.

Solar Flare Staging pics!

 

[adrian]

Staging 18mm to 13mm is preferable, partly because of concerns about nozzle sizes already mentioned, also because generally you want the more powerful motor in the booster as it has to lift the heaviest load.

Gap staging is, in my experience at least, more reliable than having the motors jammed together.

There used to be a nice kit called MIRV Gryphon, which involved a cluster of 13mm boosters in a cluster, each staging a separate 13mm sustainer. The A10-0T went out of production; meanwhile, for entirely different reasons, I didn't get to fly anything for a while and went insane from BP deprivation. The result was MIRV Gatling - six 18mm boosters in a cluster, each staging a separate 13mm sustainer. Everything lit, the booster definitely came back down, and at least one of the sustainers definitely landed as well because it was found some weeks later.

 

[hcmbanjo]

You may have seen this at the Odd'l Rockets website on the Gallery Page.
It's a C6-0 to A10-3T. The rocket was built for the 2009 EMRR Challenge, 2 Stage Kitbash. It's name: Blackbird Baked in a Pie.
The A10 is pushed into the top of the C6 about 1/8".
I know that gap-staging with ports is more reliable giving the upper stage a little more time to ignite.
It's flown three times. Every time staging went perfectly.

 

[dragon_rider10]

The Estes Solar Flare uses 18mm boosters and 13mm sustainers. I haven't flown mine yet, but I assume that it just may work... ;-)

I knew I wanted a Solar Flare, I just didn't know why! Now it all makes perfect sense. 4 13mm sustainers for the price of 3 18mm...perfect! Oh Santa...do you read these forums?
:hohoho:

 

[dragon_rider10]

You may have seen this at the Odd'l Rockets website on the Gallery Page.
It's a C6-0 to A10-3T. The rocket was built for the 2009 EMRR Challenge, 2 Stage Kitbash. It's name: Blackbird Baked in a Pie.
The A10 is pushed into the top of the C6 about 1/8".
I know that gap-staging with ports is more reliable giving the upper stage a little more time to ignite.
It's flown three times. Every time staging went perfectly.

Chris, In fact I had seen that odd little rocket on your site. Strange looking, I'll say. But perhaps it's tasty.