Good Morning all;
Working on my first avionics bay, utilizing the LOC EB-300 kit (3" diameter airframe) which includes a 'stiffy' coupler, and fear I have 'designed myself' into a corner (fortunately, apart from gluing the 'stiffy' tube into the coupler no holes have been drilled, etc.) Seeking the group's feedback in turn...
No switch band, and sampling ports would be mid-point of the coupler, right at the intersection of the airframe booster and payload bays.
Inside/comprising the bay; I had envisioned incorporating bulkhead mounted disposable charge wells like Justin featured here: https://www.rocketryforum.com/threa...hemed-build-thread.130046/page-2#post-1525111. ematches would be direct wired to the altimeter, which is a PerfectFlite Stratologger CF, powered by a 2S LiPo. LiPo has the 'factory' eFlite UMX/JST-PH connector on it, and I planned to attach a pigtail with a mating connector to the 'Batt' terminal on the Stratologger CF. Arming switch is one of the pull-pin assemblies from Lab Rat with an atmospheric sampling port doing double duty as the conduit for the arming pin; and it is this specific aspect (in concert with the absence of terminal blocks for the ematches) that has me scratching my head...
Sitting with the EB-300 on my lap, and going through the motions of how I would prep the bay for flight. I had originally thought I could insert the arming pin, connect the battery to the altimeter, and connect the ematches to the altimeter; then close up the bay. Then the 'ah ha' / 'oh sh_t!' moment; when it dawned on me that with the arming pin through the side of the coupler and into the switch, there was no way I could move the sled back and forth to terminate the ematch wires.
The only option I am coming up with (based on NO experience to date), would be to connect the ematch leads to the altimeter first (at least one set of leads would need to be long enough to allow the bay to be slid clear of the other end of the coupler) , then butt one bulkhead up to the end of the av-bay, leaving the other off, and slide the sled into final position. Insert the arming pin into the switch through the coupler wall and then reach into the open end of the coupler/bay to connect the battery to the altimeter. Lastly slip the other bulkhead over the threaded rods and secure it, closing up the bay.
I don't like the idea of needing to leave any more slack in the wires/undressed wire than I have to, especially with the wiring from the altimeter to the battery (is the ematch wiring a concern?), and I think I would need to find some way to secure the battery connector to the sled after the connection is made (to ensure they remain connected during flight), yet still be removable for post-flight disassembly.
Criticism/suggestions eagerly solicited. Is there anything I am failing to 'see' that would be a viable sequence of events? If what I am proposing is do-able, but perhaps a change to a different power connector is warranted (though I would prefer to retain the factory connectors for the balance charging it provides), what connectors would you recommend (something I can manipulate when reaching into the bay/coupler)?
Thanks as ever,
Dave
Working on my first avionics bay, utilizing the LOC EB-300 kit (3" diameter airframe) which includes a 'stiffy' coupler, and fear I have 'designed myself' into a corner (fortunately, apart from gluing the 'stiffy' tube into the coupler no holes have been drilled, etc.) Seeking the group's feedback in turn...
No switch band, and sampling ports would be mid-point of the coupler, right at the intersection of the airframe booster and payload bays.
Inside/comprising the bay; I had envisioned incorporating bulkhead mounted disposable charge wells like Justin featured here: https://www.rocketryforum.com/threa...hemed-build-thread.130046/page-2#post-1525111. ematches would be direct wired to the altimeter, which is a PerfectFlite Stratologger CF, powered by a 2S LiPo. LiPo has the 'factory' eFlite UMX/JST-PH connector on it, and I planned to attach a pigtail with a mating connector to the 'Batt' terminal on the Stratologger CF. Arming switch is one of the pull-pin assemblies from Lab Rat with an atmospheric sampling port doing double duty as the conduit for the arming pin; and it is this specific aspect (in concert with the absence of terminal blocks for the ematches) that has me scratching my head...
Sitting with the EB-300 on my lap, and going through the motions of how I would prep the bay for flight. I had originally thought I could insert the arming pin, connect the battery to the altimeter, and connect the ematches to the altimeter; then close up the bay. Then the 'ah ha' / 'oh sh_t!' moment; when it dawned on me that with the arming pin through the side of the coupler and into the switch, there was no way I could move the sled back and forth to terminate the ematch wires.
The only option I am coming up with (based on NO experience to date), would be to connect the ematch leads to the altimeter first (at least one set of leads would need to be long enough to allow the bay to be slid clear of the other end of the coupler) , then butt one bulkhead up to the end of the av-bay, leaving the other off, and slide the sled into final position. Insert the arming pin into the switch through the coupler wall and then reach into the open end of the coupler/bay to connect the battery to the altimeter. Lastly slip the other bulkhead over the threaded rods and secure it, closing up the bay.
I don't like the idea of needing to leave any more slack in the wires/undressed wire than I have to, especially with the wiring from the altimeter to the battery (is the ematch wiring a concern?), and I think I would need to find some way to secure the battery connector to the sled after the connection is made (to ensure they remain connected during flight), yet still be removable for post-flight disassembly.
Criticism/suggestions eagerly solicited. Is there anything I am failing to 'see' that would be a viable sequence of events? If what I am proposing is do-able, but perhaps a change to a different power connector is warranted (though I would prefer to retain the factory connectors for the balance charging it provides), what connectors would you recommend (something I can manipulate when reaching into the bay/coupler)?
Thanks as ever,
Dave