Staging Estes motors: 18mm to 1/2 A 13mm

[mrichhcirm]

Hey guys. Building a Taser Twin but want to keep the flights low and slow for demo purposes.

I'm thinking of staging Estes b6-0 to a 1/2A3-4T (encased in a spent 18mm motor with the nozzle knocked out). The motor casings will be taped together per the Estes instructions.
Why, you ask?
1. upper stage engines hard to come by 'round these parts: I can get c6-7 but then I'll never see the upper stage again.
2. would like to keep all phases of flight within sight of ground.

Soooo....I know that the ideal choice for 13mm upper stage is the A10-3T (big nozzle, easier ignition). Any insight into whether a B6-0 can reliably light the 1/2A3 or A3 motors with their smaller nozzles? will the scotch-tape method for securing the motors together work well here?

Thanks,

mrichhcirm.

 

[sl98]

Check out the Estes Solar Flare. It is a 18mm to 13mm 2 stage.

 

[BDB]

I've never staged an 18 to 13 mm, but I've done it plenty of times with a 24 to 18 mm configuration with no issues. The motor cases should nest into each other, so feel free to overlap them by a mm or two. Should work like a charm.

 

[Cabernut]

There's an 18mm 1/2A, the 1/2A6-2. The delay may be a bit short though.

No need for stuffing a 13mm in an empty casing.

 

[cavecentral]

1. upper stage engines hard to come by 'round these parts: I can get c6-7 but then I'll never see the upper stage again.

Does saying "Upper Stage" actually matter? I though these were just the longer delays with a different color to minimize confusion?

Never heard of them being easier to get to light for staging.

 

[GlenP]

...
Soooo....I know that the ideal choice for 13mm upper stage is the A10-3T (big nozzle, easier ignition). Any insight into whether a B6-0 can reliably light the 1/2A3 or A3 motors with their smaller nozzles? will the scotch-tape method for securing the motors together work well here?

I have successfully gap-staged from a B6-0 to an A10-3T in my modified Centuri (SEMROC) Excalibur, kind of a 3 finned version of a Nike-Apache look-alike/inspired design. The booster tube is about 10 inches long and there are 3 vent holes around the bottom of the sustainer engine mount. I don't remember if I might have used a 1/2A3-4T in the sustainer or not.

OpenRocket will help you figure out staging altitudes for different engine combinations. I think the Upper Stage designation is usually just the longer delay times, since the rocket has a bigger impulse driving it, it has a longer way to go before it slows down to reach apogee.

 

[TangoJuliet]

30+ years ago, when I was a teenager, I flew plenty of model rockets, but I never did any staged rockets. I don't really know why, I just didn't. So now I'm a little uneducated on how it's done. Can someone point me to a discussion thread with images of the gap staging technique? End to end BP engine staging I get, that one is kind of a no-brainer if you ask me. But the gap staging and the venting... That's something I want to understand better.

 

[Gus]

... Can someone point me to a discussion thread with images of the gap staging technique?...

This should help you understand a bit about what is actually going on when black powder motors stage:

[video=youtube;1Nhe5Y78PRQ]https://www.youtube.com/watch?v=1Nhe5Y78PRQ"]https://www.youtube.com/watch?v=1Nhe5Y78PRQ[/video]

 

[TangoJuliet]

Arg! YouTube is blocked by the company server! I can watch it on my Kindle Fire using the Guestnet, but I need to know the title of the video to find it. Thanks Gus.

 

[Gus]

Arg! YouTube is blocked by the company server! I can watch it on my Kindle Fire using the Guestnet, but I need to know the title of the video to find it. Thanks Gus.

"Naram 55 06 R&D Emma Kristal's high-speed video analysis of staging"

 

[TangoJuliet]

Danke!

 

[KennB]

will the scotch-tape method for securing the motors together work well here?

Please remember to use clear cellophane tape and not the "Magic Transparent" style. Any time I've seen the motors not separate properly, the Magic Transparent tape had been used.

 

[TangoJuliet]

Emma Kristal's research video project was amazing! I would love to see it reworked with better high speed video cameras from a couple of angles and more motors. Still, very enlightening.

 

[mwtoelle]

Hey guys. Building a Taser Twin but want to keep the flights low and slow for demo purposes.

I'm thinking of staging Estes b6-0 to a 1/2A3-4T (encased in a spent 18mm motor with the nozzle knocked out). The motor casings will be taped together per the Estes instructions.
Why, you ask?
1. upper stage engines hard to come by 'round these parts: I can get c6-7 but then I'll never see the upper stage again.
2. would like to keep all phases of flight within sight of ground.

Soooo....I know that the ideal choice for 13mm upper stage is the A10-3T (big nozzle, easier ignition). Any insight into whether a B6-0 can reliably light the 1/2A3 or A3 motors with their smaller nozzles? will the scotch-tape method for securing the motors together work well here?

If you can obtain A8-0 and A8-5 motors, the Taser Twin should stay in sight. The rocket will stage at a fairly low altitude and you can actually see the upper stage really accelerate upwards. I have used this motor combo on the old Apogee II which is about the same size as the Taser Twin. A B6-0 will put the rocket quite a bit higher. Also second the use of cellophane tape instead of the more commonly available and stronger Magic Transparent tape. Unfortunately, cellophane tape would need to be special ordered these days. I haven't seen it at any of the common department or office supply stores in several years in the area where I live. YMMV.

 

[Micromeister]

Really guys?
We've been staging 18mm to 13mm motors for decades. It's the easiest way to stage BP motors. actually a 13mm motor slips into the aft end of an 18mm motor (NO TAPE needed). Likewise, an 18mm motor slips nicely into the aft end of 24mm motors.

I've been flying 2 & 3 stage UFO's for as long as I can remember just this way D12-0/C6-0 and/or 3rd stage A10-3T. If you set your 13mm second stage motor in an 18mm spent motor casing with a motor block making the 13mm motor extend about 1/4 - 3/8" into you first stage booster -0 motor you should have no trouble with ignition at all.
As mentioned this is the easiest way to Stage BP motors...NO TAPE reqired.