Sunday, May 25, 2014

Weekend Update...and more to come

I have a few pictures for this week and probably a few more before the long memorial day weekend is over.  I have been busy with the wiring of the plane and it seems like a pretty daunting task but one wire at a time seems to work.  As the temps warm up around here I am spending a lot of my free computer time researching and studying the process of cutting and installing the canopy.  I am quite nervous about this aspect of the project because of the high failure rate among other builders.  I have heard it said that its almost a right of passage to crack your first canopy and spend over a $1000 to buy a new one.  Harry even suggested (in jest I hope) that I should just order a new one now.  :-)  Anyway I hope that does not come to pass.

One more exciting piece of news, my avionics have shipped!  I should have them by the end of the week.  I am really looking forward to getting them installed since that's the last major task required before I button up the forward deck.  The final big riveting job is coming up!

On to the pictures...

Speaking of the canopy, here it is ready for marking and cutting.  Travis came over and helped me bring it back upstairs so I could be ready when the temps come up a bit.

More and more wires every day.  Starting to look like a cob web in there.  Eventually I will tighten down the tie wraps and probably add a few to make it much neater and tighter.

Before picture of the wire mess I was working on Saturday.

I added a home-made ground buss bar to the mid-ship under the seat pan.  This way I only have to run one main ground wire up to the "forest of tabs" for some smaller grounds.

I also wired up the flap motor and the flap position indicator using db9 connectors.

Here is the same flap housing from the right side.
I also got around to installing the db9 connector boards I made a month or two ago.  The top on in the picture is the control stick aggregator.  I routes the various switch outputs on both sticks to the trim controller (VPX).  The bottom one does the same thing for the comm radio inputs.

2 comments:

  1. Hi Darin! Now I'm not an EE, but you may need to isolate your secondary ground busbar from the airframe aluminum. If you were connecting all grounds directly to the aluminum and using the airplane as the ground bus, I think you'd be okay if all pieces are bonded together well. It would also be okay to "home run" all grounds back to the primary bus, but I understand why you would want to avoid that. You may be creating a ground loop and causing interference via a difference of potential by essentially bonding the secondary ground bus to the aluminum, then running a ground wire back to the primary bus. I'm not completely sure if this will cause a problem, but something you may want to look into if this hasn't been brought up in design consideration.

    It's looking good man!!

    "I added a home-made ground buss bar to the mid-ship under the seat pan. This way I only have to run one main ground wire up to the "forest of tabs" for some smaller grounds."

    ReplyDelete
  2. You are probably right Shane. I don't plan on having any comm equipment grounded here and from what I understand that is the only time a ground loop is problematic. However, as I finish up my wiring I am finding that I don't have that many grounds to terminate here and it might just be wise to run them back to the ground tabs on the firewall. Thanks for pointing this out.

    ReplyDelete