Catching up on my build updates, this will be about the av-bay, which I'm mostly done with. No launch for me tomorrow, partly because of a poor weather forecast, but mostly because I'm not done yet.
Here is the bottom of the chute cannon. I'm using a .1" header for the Raven electrical connections. I made a little bulkhead that fits inside the coupler, using the the new belt sander, and marked it with some ink on the header while everything was put together inside the coupler:
Here are some more views of the H-beam tray I made with some more 15-mil fiberglass:
The nuts are just epoxied onto the sled. I was thinking that I would need to put a layer of fiberglass over them to help hold them down, but then I found out how solidly they are attached. I sanded the nuts before installing
When I was test-fitted it together, I noticed something, see if you can spot the problem:
The Raven on the bottom needs to be able to slide backwards to get off of the header pins, but I didn't leave enough clearance behind the screw terminals. So, I started over on the H-tray since the nuts were glued on more strongly than the rest of the tray. This time I made another foamcore jig to hold the H together during curing.
Here's more detail on the cannon side of the bulkhead. I could tell that I wouldn't have room for axially oriented terminals like on a regular Featherweight av-bay, so I'm installing them radially. These are just brass nuts soldered to the header with short pieces of wire.
The white tube with the holes is how the parachute harness will be attached later.
Not that you can tell in the picture above, but I filled it in with epoxy and low-density filler so that the wiring and nuts are all potted into place. To prevent the threads from getting clogged, I put some grease on the screws and installed them during curing.
Here's how I decided what length to cut the chute cannon. I installed the parachute, piston, and left some space for the charge, and marked that depth with blue tape. I arranged each of the pieces to see how much I would be able to cut down the nosecone and/or airframe. It turns out, no length reduction looks likely at the moment:
Next I glued the bulkhead onto the new H tray, and got ready to do the critical alignment of the chute cannon so that it is perfectly centered inside the cone. I put an 18mm-29mm transition ring on the end of the cannon, and assembled everything inside the cone and the coupler, with the cannon moved forward until it couldn't go any farther.
The result is shown below, which also shows the wire whip antenna placement (in lieu of the SMA connector antenna) and replacing the battery terminal block with a battery connector:
Here is the bottom of the chute cannon. I'm using a .1" header for the Raven electrical connections. I made a little bulkhead that fits inside the coupler, using the the new belt sander, and marked it with some ink on the header while everything was put together inside the coupler:
Here are some more views of the H-beam tray I made with some more 15-mil fiberglass:
The nuts are just epoxied onto the sled. I was thinking that I would need to put a layer of fiberglass over them to help hold them down, but then I found out how solidly they are attached. I sanded the nuts before installing
When I was test-fitted it together, I noticed something, see if you can spot the problem:
The Raven on the bottom needs to be able to slide backwards to get off of the header pins, but I didn't leave enough clearance behind the screw terminals. So, I started over on the H-tray since the nuts were glued on more strongly than the rest of the tray. This time I made another foamcore jig to hold the H together during curing.
Here's more detail on the cannon side of the bulkhead. I could tell that I wouldn't have room for axially oriented terminals like on a regular Featherweight av-bay, so I'm installing them radially. These are just brass nuts soldered to the header with short pieces of wire.
The white tube with the holes is how the parachute harness will be attached later.
Not that you can tell in the picture above, but I filled it in with epoxy and low-density filler so that the wiring and nuts are all potted into place. To prevent the threads from getting clogged, I put some grease on the screws and installed them during curing.
Here's how I decided what length to cut the chute cannon. I installed the parachute, piston, and left some space for the charge, and marked that depth with blue tape. I arranged each of the pieces to see how much I would be able to cut down the nosecone and/or airframe. It turns out, no length reduction looks likely at the moment:
Next I glued the bulkhead onto the new H tray, and got ready to do the critical alignment of the chute cannon so that it is perfectly centered inside the cone. I put an 18mm-29mm transition ring on the end of the cannon, and assembled everything inside the cone and the coupler, with the cannon moved forward until it couldn't go any farther.
The result is shown below, which also shows the wire whip antenna placement (in lieu of the SMA connector antenna) and replacing the battery terminal block with a battery connector: