Hi Jim,
many thanks for this. We who fly aeroplanes and not hydroplanes usually make our motor tubes from rolled paper with either PVA (Mike Stuart) or epoxy (me). I have never put in 'cooling slots, but then our motors are perhaps subject to a greater flow of cooling air ... until an early arrival with the motor still blazing away. So the mounting tubes can get scorched but (so far) I haven't had one fail.
Incidentally, here is a 'Hydrojet', one of Jim's marvelous models:
There is a video of one of Jim's models on you tube - has anyone got the link?
A further complication to flying with Rapiers is their storage. Last year I bought a large batch of really excellent L1's (100 mN 10 sec).
I now find they are difficult to light and need fairly extensive reaming out to get burning.
OK, I know how to do this, but what about for someone just starting out in rocketry?
Any thoughts on (a) storage of motors; (b) lighting those which are reluctant to start?
I have heard of guys using a drop or two of lighter fuel, or ground match heads - but I really hoped Dr Z had addressed these issues so that we could promulgate Rapier flying with a clear conscience. Oh dear!
Your thoughts on the present Rapier situation are needed!