Loc Precision released the 4" Cyclotron.

[Rocketjunkie]

Tube fin rockets do not weather cock. Found out the hard way with the 3" tube fin on a J90 and a windy day. Went the direction the rod was pointed.

 

[cls]

3" Cyclotron was my 3rd HPR rocket. Park flier on G40 or G80. Blasted it a few times with I284, J350... always ready for more. I gotta get that one out of storage.

 

[Rocketjunkie]

I had a Cyclotron but it had couplers for fins. A pop sickle stick between the fins fixed the problem. Lost it on a 54 mm Rx K160 (before CTI made them).

 

[bibbster]

Here is an .ork that I created. Tweak to fit your needs, of course.