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Posted: Wed Aug 22, 2007 5:26 am
by Novacastrian
Allows quick destruction of the enemy cost effectively, lol :twisted:

Posted: Wed Aug 22, 2007 8:43 pm
by Dornep
Very nice! I've had an idea similar to yours for about a week now. I'm planning on trying to make this and if anyone else has the materials on hand feel free to try your hand at it.

It's basically a FFR (Folding Fin Rocket) like yours only made of sleeved PVC pipe. If anyone knows what types of pipe could be sleeved together to give an OD the same as the ID of 2" SCH40 I would really like to know so I can get started on this. You wouldn't want to fire it at a sheet of plywood but I think it would be good for distance shots with the right nose cone.

Posted: Wed Aug 22, 2007 9:12 pm
by MisterSteve124
Well to make it easy you could just get a piece of pipe and cut a small section out of it lengthwise and just squeeze it inside the other pipe.

Posted: Wed Aug 22, 2007 9:38 pm
by sjog
Very nice! I like the bevel cuts to the finlets.
edit: I was on page 2. First projectile , nice w/springs!

Posted: Wed Aug 22, 2007 9:40 pm
by thespeedycicada
for the spring mechanism you could use very thin gauge sheet metal or spring steel from an old wood saw ive made a powerful crossbow using that stuff :twisted:

Posted: Wed Aug 22, 2007 10:23 pm
by Dornep
I like the spring steel for the springs idea, it would make it more damage resistant and it would be alot simpler then a complex spring setup. You could also cut up the spring band in an old lawn mower pull starter and make several rockets.

Posted: Thu Aug 23, 2007 1:19 pm
by Rock
I just made 3 more test shots (pneumatic) and it works quite well. Made a video but you can't see anything at all, crappy camera.
This prototype is not very damage resistant. I shot it with a pressure of 120psi. It hit the target with the brass cap first but the fins got bent an i had to fix it. I think that is to much work for a thing that is meant to be shot at hard targets with the violent force of a hybrid launcher. If i try a hybrid shot at a 2x mix it will probably be useless. Unless i find a better way to build such a projectile it is not worth the time.

Posted: Thu Aug 23, 2007 1:24 pm
by paaiyan
What it would be useful for is distance shots. You could devise a remote firing mechanism to release a parachute.

Posted: Thu Aug 23, 2007 1:33 pm
by jackssmirkingrevenge
Rock wrote:Unless i don't find a better way to build such a projectile it is not worth the time.
In reality you can achieve the same stabilising effects as fins by having a hollow base or lightweight tail, it must be admitted that the key appeal of fold-out fins is that they're really cool :D

Posted: Thu Aug 23, 2007 2:59 pm
by dewey-1
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Posted: Thu Aug 23, 2007 4:49 pm
by Dornep
Those spring loaded hinges would do the trick I think. You could bend them to shape and use a dremel to carve out the pvc pipe and fins so they sit flush with the pipe when the fins are closed. There is a big selection of pipe were I work and the boss told me today to take what I like so this maybe a job for this weekend. :D

Posted: Fri Aug 31, 2007 6:41 am
by Rock
Maybe another mechanism is easier to make.
Found some rocket with a simple folding fin construction.
http://www.stormbirds.net/tech_r4m_rocket.htm
and
http://www.vietnamgear.com/kit.aspx?kit=501
Maybe it's time for a new prototype...

Image

Posted: Fri Aug 31, 2007 4:50 pm
by Dornep
Awesome!

If the fins could be made to lay down backwards as it passed through something it might survive better then the other design. I'm in the process of building a large combustion with interchangable barrels to fire things like these, so it will be a couple of weeks before I start on anything like this.

What would really be cool is if you could get a hold of one of these disarmed as a replica or maybe at a military surplus store (unlikely). I found some 25mm PGU-23 HEI casings this way and got about 15 of them for 5 dollars. They fit almost perfectly into 1.5" pvc. If you could find one you could reverse engineer it find out how to make them in mass.

Very nice find!

Posted: Wed Sep 12, 2007 2:31 pm
by dewey-1
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Posted: Sun Oct 21, 2007 10:49 am
by Dornep
So you can buy the fin assembly separate from the whole rocket?

The whole deal is priced at $35.00, but if you can get the fins by themselves for $12.00 I think that's a pretty good deal. Especially if you can figure out how to reverse engineer them.

On their site it says "Vehicle is 1.385 inches diameter x 28.5 inches long".

Maybe saboted in a 2" barrel or wadded in a 1.5" barrel would work well.