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On the subject of sonotubes, does anyone know how much they weigh per inch? And what are their accurate dimensions? For example, what would a 6-inch length of 12" sonotube weigh, and what are the inside and outside diameters?

If anyone can provide that info, I'd appreciate it. Thanks!

The trouble with sonotube, is that they're not made to be precise. You can see a good deal of variance tube to tube in some cases.
 
Have you considered a funnel rocket? These add a lot of drag, but the construction is similar to a regular rocket. Here is an example.
jihgolopad2-emrr.jpg
 
Polecat Thumper on a M1297 should do the trick

That or what about a Wildman Gizmo XL on the M1297 ?
 
Three of the 3' sections of 7.5" LOC Precision BT glassed with 1 wrap of 8oz. fiberglass and LOC plastic N/C. Anti-zipper design. 3FNC about 9.5' long. 45# liftoff weight with M1297 goes to about 5,200' feet. Nice and low, easy to find. M1315 goes another 1,000' or so.

HTH, --Lance.
 
The trouble with sonotube, is that they're not made to be precise. You can see a good deal of variance tube to tube in some cases.

I have the pdf on sono tube and it's weight just have to find it on 10" it's a l.5 per foot
 
Its sad indeed:sad:....but it would still be way cool:cheers:
Skip the fancy stuff until after you get an L3 - keep it simple for the cert itself.

Some one did a really cool long burn N in a saucer for a night launch. There is a great video of it that I cannot find at the moment.
Any possibility it was the launch at 00:37 in this video? Looks like a saucer-type rocket on a big-a** sparky motor...
[video=youtube;6IiBJB0_01E]https://www.youtube.com/watch?v=6IiBJB0_01E[/video]

Be wary of thrust to weight ratios. An 800' flight based on a heavy rocket is likely under the allowable threshold.

Old-school East Coast L3's used to be in the 5,000'-6,000' range using M1315's or M1939's to stay under waivers.
Yeah, if my memory serves there was a bit of friction between Bryce's L3 and "the guys on TRF" as to whether his thrust-to-weight ratio was high enough for a cert flight.

I've got a M4770. Don't forget the M6400!
You guys are nuts... :wink:
 
Any possibility it was the launch at 00:37 in this video? Looks like a saucer-type rocket on a big-a** sparky motor...
[video=youtube;6IiBJB0_01E]https://www.youtube.com/watch?v=6IiBJB0_01E[/video]
Nope, that was an incarnation of one of Mr. Cayemberg's Pyro-Pumkins. Thanks for watching my videos though!
 
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Nope, that was an incarnation of one of Mr. Cayemberg's Pyro-Pumkins. Thanks for watching my videos though!
Ah ha! I thought it looked like it could have been a saucer in the video. And I didn't realize that video was yours until just now!

If Eric is listening I'd love to know what motor he flew in that thing.
 
Also consider the smaller 75mm high-thrust motors, such as the M1830, M2250 (both C*) or M3100/M3700 (WT). They would result in a bit higher acceleration of the pad.

Jeroen

I bought a M2250 for my L3 attempt..still on the hunt for Hardware.

Thrustcurve is saying about 4200 ft ..so time to build it fly it and get it done.

Kenny
 
I have the pdf on sono tube and it's weight just have to find it on 10" it's a l.5 per foot

The 10" sonotube is 1.5 pounds (24 oz) per foot? Did I get that right? Thanks!

Assuming the 12" and other sizes are about the same density and thickness, I can work from there.
 
To expand on Claude's funnel fin idea, Andy Schecter from the MARS group did a really innovative funnel/ring fin rocket called "The Grim Reaper" back in the late 90s:
GrimReaperLiftoff.jpg
It would easily stay below 2000 feet on an M1419W. Here's a scanned copy of the HPR article detailing its design philosophy and construction. The ringtail was added to fix the damping issue caused by having only a funnel fin.

It's not a kit but it's a cool way to solve the problem!
 
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To expand on Claude's funnel fin idea, Andy Schecter from the MARS group did a really innovative funnel/ring fin rocket called "The Grim Reaper" back in the late 90s:
View attachment 247345
It would easily stay below 2000 feet on an M1419W. Here's a scanned copy of the HPR article detailing its design philosophy and construction. The ringtail was added to fix the damping issue caused by having only a funnel fin.

It's not a kit but it's a cool way to solve the problem!

Very cool. Thanks for sharing.
 
Three of the 3' sections of 7.5" LOC Precision BT glassed with 1 wrap of 8oz. fiberglass and LOC plastic N/C. Anti-zipper design. 3FNC about 9.5' long. 45# liftoff weight with M1297 goes to about 5,200' feet. Nice and low, easy to find. M1315 goes another 1,000' or so.

HTH, --Lance.

I did the same rocket for my L3 without the Fiberglass wrap. 40# and 5600' on the M1297. Fun to watch this kind of flight and land an M flight back on the field you left from.
 
Any 10' -12' rocket with the smallest M you can get should do the trick. If you are worried, add some nose weight. Build everything extra heavy. Foam the fin can, use extra heavy parachutes and shock cords ETC. Just make sure you sim it and its still stable. it should not be hard to reach those altitudes.
 
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