Hold your igniters in place with 1/4" masking Tape... They will stay put and the tape will rip easily. This method is tried and true.
See message #3 for this thread.
https://www.rocketryforum.com/threa...rocket-that-spins-project.169137/post-2196985
Tangled the ignition leads, that got wrapped up around the body.
That was the last time I used any tape. This model is very unique. I needs for the ignitor to leave the engine as soon as possible, gently, with no yanking.
The putty/clay/gum (when cold) method works pretty well for that. The drawback is that effect I described, which now that I'm aware of it, I can actually use as an advantage, by pressing the wiring the other way, to cause the ignition side-thrust to help start the spinning sooner than normal.
Funkworks, a ring fin for stability and minimal effect on roll is a nice idea. It still would have to be mounted by some stub-fins, though those would have a lot less area, so far less of an effect on "roll drag". A cardboard tube would have a problem of squashing out-of-round when laying on its side, and this model is so big I do not even have a box for it, I just lay it in the car on top of other stuff. A ring out of plastic could solve a bit of that, though still an issue, then adding some problems of adequately glueing strongly enough. For the physics of spinning I like that idea. Though for the aesthetics, I've not cared too much for that design approach.
A way to address the roll drag would be to either cant the fins a few degrees in the direction of the spin, or to do it more simply by gluing the fins straight but adding spin tabs.
But I like the spin rate this has, at least when flown single stage. Since when staging, it does have a problem of the spin slowing down, that would be the biggest reason to cant the fins or add spin tabs.