dual deploy, patchwork on Zephyr

[Ron Soto]

so the last flight the BT got a crumple just above the fins. so... sanded out the crumple, used putty, and repainted. NOT perfect, but i'd have to remove all the decals, repaint the BT, and then (buy and) re-apply the zephyr decals. well maybe later for painting the whole BT.

i purchased the dual conversion kit from Apogee, and previously purchased an RRC2 mini. i've been playing with the RRC2 mini.. and have it setup for deployment of the drogue chute at apogee, and main chute deployment at 500'.

as for the ebay, i have that put together, and it's ready to be painted. the 18" BT... i used 400 grit sandpaper to roughen up the glassene, and have filled in the spirals.

i'm still unsure of what next.. i have ordered the Terminal blocks, and 22 gauge red/blk wire, both at Amazon. i have capsules for deployment charges.

all this.. i'm not sure i'll be ready next saturday for a dual-deployment flight. we'll see..

side note: i've been studying.. and gonna go for my L2 this saturday with the Zephyr.

ron

 

[David Schwantz]

Not really sure what your questions are. But, You will need to ground test to get BP charges correct, probably need to rebalance with an added 18" of length, Need to attach another shock cord, make sure new ebay does not jam in airframe, wire battery, add switch, vent new tube, add vent holes to ebay.

 

[waltr]

And, I am concerned about the section of BT you repaired. Sanding out bumps further weakens the tube which is added to the structural damage of the buckled cardboard.

The added weight of the ebay also increases the force on the lower BT.

If tube seems stiff and you don't fly High Thrust motors it can be fine and good for many flights.

 

[Ron Soto]

And, I am concerned about the section of BT you repaired. Sanding out bumps further weakens the tube which is added to the structural damage of the buckled cardboard.

The added weight of the ebay also increases the force on the lower BT.

If tube seems stiff and you don't fly High Thrust motors it can be fine and good for many flights.

bought a dual conversion kit for the zephyr.. and i may redo the BT now.

ron

 

[kswing]

Depending on where your centering rings and fin tabs fit, you might be able to slide a portion of coupler tube in to reinforce where the BT crumpled.

 

[Ron Soto]

Depending on where your centering rings and fin tabs fit, you might be able to slide a portion of coupler tube in to reinforce where the BT crumpled.

great thought... unfortunately this crumple is 'just' at the top of the fins, therefore a coupler will not work. (i thought of this exact repair). So.. since we'll be pushed back a couple 'o weeks due to rain:

. remove all decals from BT.
. sand entire BT getting ready for another couple of coats of white, and 2 to 3 shots of clear coat.
. at areas of crumple sand down to BT, and install fiberglass sheeting about 1.5 inches wide with epoxy to beef up the BT where crumple exists. (thinking i'll just wrap the entire rocket at the fins though).
. re-apply decals.
. get ready for a J.

the base zephyr will be going up on J on her next flight for my L2. after that, she'll be used for getting me started in dual-deploy as i'll be getting another rocket for me, and an Athena for my wife (a mid to high power vehicle, that if she wants to.. can get her L1.

r-

 

[Handeman]

I agree with @waltr, just sanding down and painting wrinkled cardboard BT just makes it weaker, and obviously it wasn't strong enough to begin with. This is a problem you'll come across a lot if you use shipping tubes to scratch build rockets with.

You can always split a piece of BT, put some fin slots in it and glue it on the outside about 1 caliber above and below the wrinkle to reenforce the BT. It' won't look the best, but it will works. Also a wrap or two of 4 or 6 oz fiberglass clothe will also work.

Good Luck and I hope if flies well.

 

[Ron Soto]

I agree with @waltr, just sanding down and painting wrinkled cardboard BT just makes it weaker, and obviously it wasn't strong enough to begin with. This is a problem you'll come across a lot if you use shipping tubes to scratch build rockets with.

You can always split a piece of BT, put some fin slots in it and glue it on the outside about 1 caliber above and below the wrinkle to reenforce the BT. It' won't look the best, but it will works. Also a wrap or two of 4 or 6 oz fiberglass clothe will also work.

Good Luck and I hope if flies well.

Thanks for the info on the fiber- glass weight.

As I mentioned, i'm going to strip the body tube of paint in the area where the crumple was, and rap with fiber glass. Obviously the repaired area will look like poop, but the vehicle is going to serve as my DD tester now, as I'm researching a new fiberglass buy/build. (Maybe Darkstar Jr as my first FG kit).

R-

 

[Aeva]

If there is space inside the rocket in the damaged section, I would put a fiberglassed coupler tube in there. Fiberglass it using UPScaler's method, then epoxy it to the damaged section on the inside. That way you're not adding anything to the outside of the rocket that might affect its shape.

 

[thzero]

If there is space inside the rocket in the damaged section, I would put a fiberglassed coupler tube in there. Fiberglass it using UPScaler's method, then epoxy it to the damaged section on the inside. That way you're not adding anything to the outside of the rocket that might affect its shape.

I did this to create custom coupler on 5.5" rocket.