I spent a lot of time in the aft fuselage the week before last, running and securing the wires for the electric trim. It sure is a pain to get all the way back in there. You need both hands above your head to do some of the work, but it is so tight that your elbows hit the bulkhead and won't let you put your arms up there. So, you have to get your arms above your head before moving into the last bay.
I mounted the trim servo in the elevator and puzzled out how to secure the wires as they went from the elevator, into the horizontal stab and then to the aft fuselage. I hooked up the front end of the trim wire and did a complete functional test - front seat trim switch, rear seat trim switch, trim disable switch on stick, rear seat trim disable switch on side console. It all worked.
I had hoped to get the roll trim hooked up that week too, but I ran out of butt splices to hook up the wires. I was going to finish the mechanical installation, but I couldn't find the long piece of 5/16 aluminum tube used to go between the servo and stick. I found two pieces half as long as I needed, but the long guy was missing. I finally remembered what happened - I had screwed up the flap pushrods, and had to use that long piece of tube to make them from. I had planned on replacing it and then forgot about it. Coincidentally I had purchased a long piece of the same tubing a few weeks ago to make some spacers from. I had just made a few spacers earlier that day - I measured how much remained of the tubing and it was a half-inch too short. If I had only noticed that I had those two shorter pieces of tubing I could have used them for the spacers instead. Oh well. One more thing to order from Van's.
I've spent a lot of time over the last two weeks messing around with dimmers for the GNS-430 GPS, GTX-327 transponder, Microair com, Garmin CDI, Van's engine instruments, etc. There are several different types of light technologies involved, and each one has its own curve of light intensity vs input voltage. And the GNS-430 and GTX-327 each has several variables that you can set to customize the intensity vs input voltage. I don't want a separate dimmer knob for each unit, so I need to figure out how to set them up to allow me to use as few dimmer knobs as possible, yet have the lighting on all units remain in balance no matter what intensity I want. I'll have a lot more empathy for the poor designer next time I do a night lighting evaluation of an avionics mod, and note a problem with the lighting balance.
I think I am zeroing in on a solution. The GNS-430 and GTX-327 will get their own separate rheostat, as the solid state dimmer I have for the LED flood lights won't go to a low enough voltage to work with the logic built into those units. They are designed to stop following the dimmer and set the intensity based on a photocell for daylight operations. The Microair com backlighting will work nicely if I feed it from the solid state dimmer for the LEDs. And the CDI, engine instruments, etc will have to be on their own solid state dimmer, as they are all incandescent lights they should have roughly the same curve of intensity vs voltage (I hope - I haven't proven this yet)
I had originally planned to just have the LED flood lights, so many of my instruments do not have internal lighting. But some of them do, and I've decided to use the internal lighting on the CDI and engine instruments. The EFIS is lit, and it has attitude, heading, airspeed and altitude. The CDI and engine instruments will be internally lit. The round dial airspeed and altimeter are of lower importance, so I can accept a bit lower light level from the LED floods.
I also pulled out the avionics rack for a while so I could reroute part of the wiring harness that was too close to some structure.
