Need Build Advice

I'm rebuilding my Mirage (see the thread about using a spacer between a S/U motor and a Slimline retainer to see why). I've salvaged the motor/fin section and put 4.5' of 2.5" quantum tube above that. Rather than add the payload section of the same diameter, I put an inverted PML urethane tail cone as a transition and put 1.5' of 1.5" phenolic tubing into that. It's topped with a PML urethane conical nose.

Now, whether I use the regular Mirage two piece recovery, or hook them together to come down in one piece, it's going to come down on the nose. From what I hear, phenolic tubing won't handle this. I want to strengthen it. The problem is (1) it's already glued into the transition and (2) even if it weren't the tube barely fits into the transition as it is as so glassing the tube (or buying it preglassed) wasn't an option.

So, I'm stuck with either:
(a) trying to glass the part of the tube sticking out and taking the chance on gumming up the transition with epoxy, or
(b) finding something strong yet thin that'll slip fairly tightly over the 1.65" OD.

I tried to go with (a) with some Aerosleeve, but I can't get it to fold double at the bottom to give a good edge against the transition, and still pull tight against the tube.

I think (b) would be better cosmetically, because although the payload tube fits tightly in the transition, the "base" of the tail cone has quite a lip on it. A tube over the payload tube would help fill this. Trouble is it'd have to be fairly thin walled since the nose cone doesn't have much lip beyond the 38mm tube.

I did try putting some 38mm coupler down the payload section. There's drips of epoxy stuck to the inside of the tube about halfway down. I chipped off what I could with a piece of pipe but it wasn't enough.

So, any ideas of what to slip over or wrap around the tube without making a mess of the transition?

If glassing is out of the question I would keep the two sections attached to one chute for recovery. Size the chute for < 15 ft./sec. decent rate, 12-10 ft./sec. would be best. Use 20 feet or more of shock cord with the chute attached around 3 feet from the upper section. The lower section should hit first allowing the upper section to decend the last 10 ft. or so at even a slower decent rate. Sounds like an intresting mod.

steve

Originally posted by DumasBro2
If glassing is out of the question I would keep the two sections attached to one chute for recovery. Size the chute for < 15 ft./sec. decent rate, 12-10 ft./sec. would be best. Use 20 feet or more of shock cord with the chute attached around 3 feet from the upper section. The lower section should hit first allowing the upper section to decend the last 10 ft. or so at even a slower decent rate. Sounds like an intresting mod.

steve

Click to expand...

That sounds like the most workable solution. If half the weight is taken off the chute a second before the nose hits, it may just slow down enough and start to drift a bit more enough to reduce the shock.

I may still try to beef up the payload tube with something resilient (I'm thinking of trying clear silicone caulking) covered with a wrap of some sort. And I can plan ahead this time and preglass another section if thisone cracks.