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Show a picture of BEHIND your panel

bobmarkert

Well Known Member
I spent an enjoyable hour searching the thread ?Show us your Panel?, but what I really need is ?show us behind your panel?. Stein will build my harness but I need to locate the remote boxes so the connectors don?t conflict and the remote transponder is high enough to be removed through the access door I built into the baggage compartment of my RV8. I assume the area on the left of the pane is off limits due to the GX pilot, GTN 650 and PAR100EX taking up all the real estate. An suggestions and/or pictures on how to place/orient the following on the right side? Criteria are harness connections, access and removal of remote transponder through Baggage access. Thank you.
GTX 23ES remote transponder
GDL 39 ADS-B
GSU73 ADAHARS
Batter back up for G3X (I don?t know what this looks like or size
PARA100EX remote radio

And if it makes sense to do a panel mount transponder instead of the remote is there a GTX23EX comparable unit?

Sorry for pic quality, pic of PDF from computer screen

Thanks
Bob Markert
303 882-7410
 
Here's mine.
Rigging156.jpg

Rigging157.jpg
 
Randy, that's beautiful.

I spent 2 hours on my back in the footwell of the RV-6 cleaning things up from 12 years of changes "under the hood". It looks better now, but never, ever looked that neat and clean.
 
We're Not Worthy....

Geez Randy, that's an incredible job. Like the others, I thought mine was good but while tidy, it's a rat's nest in comparison.
 
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Randy's wiring is nice. I'd say it's new GA aircraft certificated standard. If you bought a new Cirrus it would be just as neat, if not better.

To get wiring like Randy's you need to have comprehensive drawings and plan ahead...you need know what you're doing in advance. You can't get that quality by having a plan that involves simply installing one wire and then thinking about the next one. You have to have a "big picture".

The fact that so many posters are saying "wow" to Randy's workmanship is a fair indication that the "behind the scenes" wiring on the average Experimental aircraft is pretty woeful.

I think we should have a new permanent thread called "Show us BEHIND your panel". Instead of getting photos of a whole lot of cheque book front panels done by Steinair we might then get some idea of what builders themselves are actually doing back behind the panel. ;)
 
Randy's wiring is nice. I'd say it's new GA aircraft certificated standard. If you bought a new Cirrus it would be just as neat, if not better.

Bob,
Are your serious about the Cirrus? I've never seen behind a certified aircraft panel that was remotely close to Randy's.
Someone snap a photo under the panel of a Cirrus for us.

Mark
 
Footwell looking up...

Randy,

That's amazing! Just starting to wire my 9A. Is that picture taken from the footwell looking up, or is it looking down from an access panel, or maybe before you closed up the front top skins. Just curious as I try to determine how to mount various electrical devices behind the panel for best access later on.

I agree this should be a permanent thread. I've looked for behind panel pictures before without much luck.

Thanks,
Michael-
 
Back of similar panel

This is in my RV8a

back.jpg


Here's the back looking from the right, bare wire for the GDL-39 can be seen going into the MFD. I'm mounting the GDL on the back of the far right side of the panel. This way I can reach under and sync with an ipad if I want and also remove it if I want it in another plane

backside.jpg


Here is looking from the left. GX pilot/GTN/audio panel and radio stack. Tight fit but it works

remotegtx.jpg


This is looking towards the tail and shows the remote mounted transponder, as well and the magnetometer position

panelpower.jpg


Here's the panel powered up for the first time this evening

Kai
 
Bob,
Are your serious about the Cirrus? I've never seen behind a certified aircraft panel that was remotely close to Randy's.
Someone snap a photo under the panel of a Cirrus for us.

Mark
No need to snap a picture behind a Cirrus panel. I own one and work on many. They are NOT even remotely close to that beautiful wiring job. In fact compared that picture I would say they look positively slovenly.
 
Bob,
Are your serious about the Cirrus? I've never seen behind a certified aircraft panel that was remotely close to Randy's.
Someone snap a photo under the panel of a Cirrus for us.

Mark

Well, Roger Whittier says the Cirrus wiring is not as good but I took a long look at a brand new SR22 a few months back and the wiring harness was VERY slick. Maybe they've improved. ;)

Randy's wiring is lovely, but if you get Stein or Stark, or any good professional, to fully wire your aircraft you'll get pretty much the same thing.

I've attached a photo I've posted before of the wiring on a radio stack for a Cessna 206. It's nice too. It's a good standard, but no more than might be expected from a professional who knows what the final product is going to look like before he starts.


photo sharing websites
 
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This is in my RV8a

back.jpg


Kai,

A heads up for you and anyone else using the GSU 73 mount from Avionics Systems in an RV8 panel.

I have found that when using that mount, the bottom of the instrument panel needs to be "tied" to something forward. Otherwise, the weight of the GSU 73 causes the panel to flex. This manifests itself in the GSU 73 unable to calibrate the magnetometer, or pass the engine run up test. Or, if you happen to get past those steps, you might lose your attitude while flying formation with another G3X equipped RV8 when you both hit the same bump!:D Both planes had the GSU 73 mounted to an "unstiffened" panel.
 
Geez guys, thanks for the comments. It's not that hard, really. Here's a couple of tips that I've learned over the years.

1. As it was said before, have a plan. Know where everything is and will be.
2. Start separating wires into major bundles early down in the tunnel like Radio, Power, Ground, etc. Within those groups, have sub-bundles like Nav, Comm, GPS, etc. I like to keep the power wires away from the radio wires as early as possible to cut down on interference.
3. I wire from the back to the front. I leave behind the panel to last. Leave all the tales long so you can route wires where you want to, not where you have to.
4. Once everything is behind the panel, wire up one device at a time and secure the bundles appropriately.

I'm sure I'm leaving out a few things, but that's the big picture. You can do it just like I've done it. It doesn't take any extraordinary skill or anything, just some patience.
 
Awesome

Randy, Your wiring is AWESOME.

I worked on F-4j's as a "behind the panel" avionics/missile guidance and fire control tech in VMFA-334. You would think that my behind the panel looks like yours. However, it does not!! My behind panel looks a lot more like Van's demo aircraft panels. If you have ever taken a photo "under and behind" a Van's panel you will see it is a more typical "spaghetti wiring" job than most would think. (Sorry, I can't find a photo I took under a Van's panel)

YMMV but Just info for those that are intimidated by Randy's awesome wiring job. Make it neat as you can so that you can trace problems. You don't have to make it looks like Randy's, especially for those that are "electrically challenged". :D

ps... and yes, those are big service loops that can be pulled thru my easily removable front access panels. The panel is a beautifully sculptured piece from Laird Owens and no, I don't know if he still makes them. :)

dyajwl.jpg


b4dd0k.jpg
 
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Panel flex

Jon,

Good to get this feed back, how did you go about fixing this? Would tying the back end of the bracket to the forward baggage bulkhead be sufficient?

Kai
 
Like Gary says, behind the panel does not have to look like Randy's work to be safe and functional. The typical rental fleet sure does not look anywhere near Randy's example of fine work.

It is much easier when you have wide open access to everything to make it more like Randy's example. Closed up airplanes and many upgrades can leave it looking messy.

I for one went thru several upgrades and I vowed to basically start over with this new upgrade. I don't however have the access that I had the first go round so while it won't end up looking like Randy's, it will be functional and safe and better than it was after all the prior upgrades.

The important things for me are:

  • Overcurrent Protection is Priority #1!
  • Keep the power wire groups separate from the data lines
  • Leave service loops
  • Label everything
  • Provide strain relief
  • Properly secure wire bundles
  • Protect wires from rubbing against edges or corners
 
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Wiring

After 20 years in Air Force, most recently working F16's, I don't think I would run wires any different. Now the RV will not pull as many G's as the 16, but if you think about doing any aerobatics and pulling some, you will seriously think about binding wires together as well as to bulkhear, stringer, or some other solid point. Although not heavy wire will move under stress (G's) and this can lead to chaffing as well as breaking. Just my two cents
 
Randy,

That's amazing! Just starting to wire my 9A. Is that picture taken from the footwell looking up, or is it looking down from an access panel, or maybe before you closed up the front top skins. Just curious as I try to determine how to mount various electrical devices behind the panel for best access later on.

I agree this should be a permanent thread. I've looked for behind panel pictures before without much luck.

Thanks,
Michael-

It's from above with the access panel removed. On the Rockets, the boot cowl (as it's called) is removable.
 
Quick view

OK, not many are courageous enough to show their panel - let me throw mine out there so that the rest of you will step up.


Here's me trying to find a bad ground:





:)
 
I would suggest that showing any pictures before you have installed your skins does not give you the true "picture". The only picture you care about is the one you have to look at when you are on your back or looking through any access panels you may have.
If everyone was forced to wire under thier panels after skins where put on, you would see things very differently. Sure, your radio stack, and some other things should be prewired harnesses, but the point to point power wiring, ignition switch, master, and other switch wiring.... I do not care how good your imagination is, you just can not get a feel for what access will be like unless you are staring at it from the position you will have to maintain it from. Oh, if I only knew then....and I thought I nailed it!

I am doing an "upgrade" to my buss and fuse wiring. I wish I would have forced myself to do the original work while crawling on my back with the panel and all instruments, avionics, and devices installed.
 
Jon,

Good to get this feed back, how did you go about fixing this? Would tying the back end of the bracket to the forward baggage bulkhead be sufficient?

Kai

Kai,
Mine is a tail dragger, so I tied the panel under the MFD back to a cross brace on the gear tower aft side. I just used a piece of .063 about 6 inches wide. Not sure what you can do on the A model. Probably just a piece of .125 angle secured below the left side of the MFD and tied all the way to the fwd baggage aft wall/fwd baggage floor intersection would do it.
Good luck,
 
Jon - an RV-8 panel upgrade is an excercise in creative yoga. I'm almost done with mine and when I finally get around to the write-up I think it will amuse a lot of people. More important is that I hope it helps people think about how they build their "second" panel :)
 
Kai, that was exactly what I was hoping for.. Thanks for the pics. They will help me plan behind my panel.
Bob
 
Here's the front of my HR-II panel. An iPOD is mounted on the right-most blank 3" cutout and connects to the audio signals brought out on the 15-pin connector below it.

IMG_1435.JPG



Here's the back of my panel. There is a bunch of custom avionics that I built, including audio mixer, wig-wag controller, annunciator controller a 25-pin wiring hub and a 9-pin wiring hub (SkyView Network). Note that Dynon's SkyView network hub is a direct copy of mine. Still waiting for royalty check....

IMG_1436.JPG


IMG_1439.JPG


IMG_1467.JPG


IMG_1468.JPG
 
Nice Vern. I've used your products before. Very innovative stuff.

I tried to stay away from cable ties as much as possible. Those things always tear up my hands when I try to reach in for something. I guess I never invested in a pair of snips that would cut the end of the tie wrap without leaving a sharp point.
 
Nice Vern. I've used your products before. Very innovative stuff.

I tried to stay away from cable ties as much as possible. Those things always tear up my hands when I try to reach in for something. I guess I never invested in a pair of snips that would cut the end of the tie wrap without leaving a sharp point.

Thanks Randy. Your Rocket site has been very valuable to me. The HR-II kit is so primitive, with no instructions. To compound the problem, I've made many modifications, such as adding the F1 slider.
 
Jonathan, I know this is a "back of the panel" thread but it looks like you and I are doing the exact same plan. I'd really like to see the front of your panel. Is it posted anywhere ?
 
I'm not against connectors, we all know they are required to make things work.
I'm opposed to excess connectors. Each connection is 3 potential faults (as Bob N said in his book) Each wire-to-terminal, and the connection. That increases the number of fault points when troubleshooting.
So I wired directly from the switch to the wing tip nav lights, if I must remove the wing, cut the wires. I can add connectors when I put it back together.
The same with any other system where this applies.
Later I may regret it, but right now it's easier, and lighter.
 
My panel is on the Show Us Your Panel thread on the RV8 area (next to last page). My goal is a mini-fighter plane look with ease of use as a goal.

I agree with the point relating to reliability. This has to be balanced with ease of maintenance. The RV8 has a small panel and not easily accessed. Though not a trivial effort, the entire main panel can be removed for upgrade and repair.

One point is to pay attention to is connector ampere ratings. I chose 13 amp rated units. Many are only rated for 5 amps.
 
I wired the sub-panel, then used Molex and DB connectors to make easily removable.

The Molex/AMP Mate-N-Lock type connectors are relatively cheap devices and were probably initially designed for less demanding applications (disk drives). I have boxes of them and I'm happy to use them but I wont use them for critical applications and I know that a lot of people feel the same.

For my subpanel disconnect of power wiring I used Mil-C-26482 circular connectors (Series 2 crimped contacts) with M 39029 gold plated copper alloy pins and sockets. See photo.

I agree with Scott Emery in that minimising connections is advantageous but service access is also very important and can be a safety factor in itself. There's a lot to be said for being able to easily remove an instrument panel, particularly in a 2 seat slider.

 
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Am I the only one brave enough to show a normal wiring job ? This was done by the builder, not me. I added most of the string ties to clean it up and provide some support.

i5xc77.jpg

2ui9115.jpg
 
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