Last night I ordered a blackhawk 38 kit from wild man for my big winter build. As such I want to go pretty all out with it and try a bunch of stuff. Before buying parts though I wanted to lay out my plan and get advice on anything that might be a bad idea or not work.
Goal:
* experience building a HP minimum diameter rocket
* optimized av bay setup, possibly redundant
* build with minimal use of metallic hardware, eliminate all-thread
* tip to tip practice (maybe)
* try out another avionics package (i have used an rrc3 in the past)
For the altimeter I want to use the Eggtimer TRS. I have some concerns about it working inside the airframe since the kit uses some graphite in the tube layup instead of just straight fiberglass. Does anyone have any experience with either an egg finder in this airframe or the egg timer wifi switch? To protect the whip antenna I will likely use a small bit of bt2 with a layer of kevlar on it. this would be affixed to the avbay bulk plate.
The biggest design challenge I think will be removing the all thread from the construction of the avbay. I don't think it is particularly complicated, however it is non standard setup. I have two ideas on how to accomplish this. The first would be to 3d print a custom sled using a high strength plastic like nylon or polycarb and gluing in some nuts in the structure. Then I could use machine screws to close everything up, kind of similar to a normal avbay. In this case the forces would all be carried through the 3d printed sled. That is my major concern with this design, though it would probably result in the best packaging of the electronics. Obviously tensile testing would be needed to confirm the part design. What would a reasonably safe tensile strength be to carry the forces at deployment (using either stock parachute or large streamer)?
The other idea I had was to do something similar to the apogee components e-bay kits except using fiberglass or kevlar. This would allow me to put a couple layers of uni fiber in the layup schedule which should help with the tensile strength. This is likely the more straightforward option, though it doesn't lead to as clean of a setup.
For motor retention I will use a slimline retainer. I fly at MMMSC which requires active retention. I know this will diminish performance some, but I might make some of it up by eliminating rail buttons and using fly away guides.
I also plan on using some carbon to reenforce the shock cord anchor.
Goal:
* experience building a HP minimum diameter rocket
* optimized av bay setup, possibly redundant
* build with minimal use of metallic hardware, eliminate all-thread
* tip to tip practice (maybe)
* try out another avionics package (i have used an rrc3 in the past)
For the altimeter I want to use the Eggtimer TRS. I have some concerns about it working inside the airframe since the kit uses some graphite in the tube layup instead of just straight fiberglass. Does anyone have any experience with either an egg finder in this airframe or the egg timer wifi switch? To protect the whip antenna I will likely use a small bit of bt2 with a layer of kevlar on it. this would be affixed to the avbay bulk plate.
The biggest design challenge I think will be removing the all thread from the construction of the avbay. I don't think it is particularly complicated, however it is non standard setup. I have two ideas on how to accomplish this. The first would be to 3d print a custom sled using a high strength plastic like nylon or polycarb and gluing in some nuts in the structure. Then I could use machine screws to close everything up, kind of similar to a normal avbay. In this case the forces would all be carried through the 3d printed sled. That is my major concern with this design, though it would probably result in the best packaging of the electronics. Obviously tensile testing would be needed to confirm the part design. What would a reasonably safe tensile strength be to carry the forces at deployment (using either stock parachute or large streamer)?
The other idea I had was to do something similar to the apogee components e-bay kits except using fiberglass or kevlar. This would allow me to put a couple layers of uni fiber in the layup schedule which should help with the tensile strength. This is likely the more straightforward option, though it doesn't lead to as clean of a setup.
For motor retention I will use a slimline retainer. I fly at MMMSC which requires active retention. I know this will diminish performance some, but I might make some of it up by eliminating rail buttons and using fly away guides.
I also plan on using some carbon to reenforce the shock cord anchor.