Launch platform

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Rex Fynns
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Launch platform

Postby Rex Fynns » Sat Jul 08, 2017 11:45 am

G'day,

Would the following work and or what issues with this design for a launch pad for MD high speed light weight rocket (24mm x 650mm 35gm).

Steel plate base 10mm thick with 3 equal spaced 6mm rods positioned on the triangular points such that the 3 finned rocket slides neatly down between the rods. Possibly incorporate a centre hole on the base for the efflux to try and avoid inducing any vibration into the launch rods, not sure it will be necessary though.

I am chasing speed so trying to avoid any external body tube mounted guides.

Thoughts?

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Re: Launch platform

Postby Oldboy » Sat Jul 08, 2017 12:33 pm

Sounds fine.
Look up towers
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OverTheTop
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Re: Launch platform

Postby OverTheTop » Sat Jul 08, 2017 2:45 pm

Hi RF. As Oldboy said, search "launch towers".

One thing with the flat plate. Make sure the rocket does not sit down on the plate or you can end up with "Bernoulli Lock". There is a significant possibility the rocket will sit, with full thrust running, suctioned down to the plate.
http://www.rocketryforum.com/showthread ... alled-that

Most towers sit on the ground and are stabilised by guy wires. I guess a smaller one could still tripod mount (or similar).
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Re: Launch platform

Postby OverTheTop » Sat Jul 08, 2017 5:50 pm

Forgot to mention. You might also find something of interest if you search for "piston launcher" :)
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Rex Fynns
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Re: Launch platform

Postby Rex Fynns » Sat Jul 08, 2017 10:36 pm

Thanks Gents,

I did do a bit of lunch tower searching (lazy man style) looking for pics but could not find much other than the single rod/guide stuff.

Common dog would dictate not to sit the rockets bum on the plate for several reason but I hadn't considered Bernoulli as one of them, but now that you mention it I see how it could occur. I believe you can replicate this principal with a water hose against a flat surface.

Piston launcher ay.....where I'm from we call em a Spud Gun with Sabot, good for the first 500' but ignition sequencing is tricky :wink:

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Re: Launch platform

Postby OverTheTop » Sat Jul 08, 2017 11:29 pm

There are no problems with ignition (midair) with piston launchers. The rocket motor provides the gas and is lit on the launcher.
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Re: Launch platform

Postby Viking » Sun Jul 09, 2017 11:35 am

Simon
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