Winter 2006-2007 Rocket Projects
Level 3 Cert Project
Today was getting the basics of the electronics bay together. I made a template in Visio for the layout of the all-thread rods, terminals and u-bolt for the bulkheads. This made it much easier to get everything aligned just right. Then I drilled the holes through all four bulkheads as one operation. (You can see the Visio diagrams of this and the layout and wiring for the electronics sled here.)
I've been struggling with decent terminals for the inside of the bulkhead in recent projects. This time I found something that seems to work really well. I'm using these terminals that crimp, heat shrink and when shrinking have solder inside that melts around the wire creating a tremendously tough terminal connection. Given my horrible soldering this is a god send. They are McMaster part #9983K17.
Also used are thumb screws (McMaster part #92741A110) on the #6 brass screws that serve as terminals. The thumb screws are much easier to work with in the field. They then get capped off with high-temp plastic covers (McMaster part #84735K16)to protect the assembly from ejection gas.
Here you can see the access holes for arming the electronics. Two per side, one to connect the charges to the altimeter and one to power the altimeter with dual electronics installed.
Here's the sled for the electronics coming together. Due to issues with the G-Wiz DCS I've rigged the sled to use the Perfect Flight MAWD and the G-Wiz MC for this flight. I've now been using terminal blocks and quick disconnects for connecting charges to the sled. The switches are from www.digikey.com part number EG1018-ND DTDP switches wired to activate when in the out position. All wiring is shrink-wrapped and tacked down to the board.
