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Best time to install fuselage wiring harness?

bertschb

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I'm pretty much done with the first three kits and waiting for the Finish kit. I have not installed the interior yet and I haven't attached the tail pieces (HS, VS, rudder, etc.). I have the Stein fuselage wiring harness that I bought last summer sitting on a shelf. Is this a good time to install it?

Sorry for the rookie question. First time builder here.
 
I'm pretty much done with the first three kits and waiting for the Finish kit. I have not installed the interior yet and I haven't attached the tail pieces (HS, VS, rudder, etc.). I have the Stein fuselage wiring harness that I bought last summer sitting on a shelf. Is this a good time to install it?

Sorry for the rookie question. First time builder here.
In my humble opinion - yes, get your main wiring harness laid in and routed where it needs to go. The snap bushings can be a tad challenging down in the tunnel and aft. Just not room for 2 hands…. You can take a 2 inch long piece of 3/4” CPVC water pipe and cut
a section of it out long ways just big enough to allow it to slip over all the wires. Put the snap pushing on the very end of that opened up and it becomes a one hand job. Good luck
 
A bit off topic, but I don’t have the fuselage wiring harness. Is there much advantage in getting this from Stein (I guess Vans doesn’t sell this?) as opposed to wiring up everything myself?
 
A bit off topic, but I don’t have the fuselage wiring harness. Is there much advantage in getting this from Stein (I guess Vans doesn’t sell this?) as opposed to wiring up everything myself?
I guess it comes down to cost vs time. Wiring yourself is completely doable but it will take planning and tools. Having a wiring harness built by Stein is very satisfying but it comes with a cost. Ultimately you will want to modify things yourself so there’s that. The harness that Vans sells is built with some basic assumptions about equipment and tries to be agnostic to the avionics that you will use. The Stein harness is more of a custom job to whatever you will be ultimately using.
 
I guess it comes down to cost vs time. Wiring yourself is completely doable but it will take planning and tools. Having a wiring harness built by Stein is very satisfying but it comes with a cost. Ultimately you will want to modify things yourself so there’s that. The harness that Vans sells is built with some basic assumptions about equipment and tries to be agnostic to the avionics that you will use. The Stein harness is more of a custom job to whatever you will be ultimately using.
That’s all true. I figured avionics and lighting is so custom anyway, that a standard harness wouldn’t work in most cases. I don’t even think Vans sells the WH-0000125 (?) main harness anymore, do they?
 
That’s all true. I figured avionics and lighting is so custom anyway, that a standard harness wouldn’t work in most cases. I don’t even think Vans sells the WH-0000125 (?) main harness anymore, do they?
I just searched on the online Vans store for it and got no hits. I must admit that I am surprised.
 
A bit off topic, but I don’t have the fuselage wiring harness. Is there much advantage in getting this from Stein (I guess Vans doesn’t sell this?) as opposed to wiring up everything myself?
I had Stein build my fuselage harness last year when I first started my project. At that time I knew NOTHING about anything. Now that I know a teeny bit more I probably should have done my own harness. Here's why:

I ended up going with four CiES fuel senders. I didn't tell Stein about that when they built my harness because I barely understood what the harness was for and had no idea I'd be going with quad CiES senders. I have to wire the senders myself now. My fault, not Steins! I ended up getting AeroLED Vxi wingtip lights and Stein doesn't support them (long story) so I have to wire those myself as well.

Vans uses Molex connectors in the aft fuselage harness and Stein uses Molex connectors so their harness is compatible with Vans. There are a lot of people who don't like Molex connectors. I know I had trouble with the micro-Molex connector used for the elevator trim motor and replaced it with D-Sub pins. I may replace the Molex connectors in my harnesses with Deutsch connectors. I suspect Stein may have used Deutsch connectors if I had asked but I'm not sure.

There is some debate recently about the quality of CAN bus wires in the harnesses if you have a long Can Bus run. That's another topic but again, you can use whatever wire you want if you're building your own harness.

I'm not being critical of Stein. They do FANTASTIC work and I plan to use them to build my panel. But, if you deviate from the plans at all, you may be better off building your own harness.

As a new builder, my opinion isn't even worth $.02 but there ya go...
 
I think that the best time to install a wiring harness is as soon as you've made the final decisions what you're installing. The more that the fuselage is built-up, once the basic structure is complete, the harder it'll be. Things like the seat pan, the side panels, etc., all complicate the wiring installation. Also, the more you deviate from the plans, even in minor details, the more difficult it'll be, because that can lead to unexpected routing issues.

Dave
 
I had Stein build my fuselage harness last year when I first started my project. At that time I knew NOTHING about anything. Now that I know a teeny bit more I probably should have done my own harness. Here's why:

I ended up going with four CiES fuel senders. I didn't tell Stein about that when they built my harness because I barely understood what the harness was for and had no idea I'd be going with quad CiES senders. I have to wire the senders myself now. My fault, not Steins! I ended up getting AeroLED Vxi wingtip lights and Stein doesn't support them (long story) so I have to wire those myself as well.

Vans uses Molex connectors in the aft fuselage harness and Stein uses Molex connectors so their harness is compatible with Vans. There are a lot of people who don't like Molex connectors. I know I had trouble with the micro-Molex connector used for the elevator trim motor and replaced it with D-Sub pins. I may replace the Molex connectors in my harnesses with Deutsch connectors. I suspect Stein may have used Deutsch connectors if I had asked but I'm not sure.

There is some debate recently about the quality of CAN bus wires in the harnesses if you have a long Can Bus run. That's another topic but again, you can use whatever wire you want if you're building your own harness.

I'm not being critical of Stein. They do FANTASTIC work and I plan to use them to build my panel. But, if you deviate from the plans at all, you may be better off building your own harness.

As a new builder, my opinion isn't even worth $.02 but there ya go...
These are good points and essentially the reason why I have been working on my own wiring. I have all my avionics now and several spools of wire. I’m using a VPX as well so I figured with all these additions, there isn’t much left that is stock and that which is, should be pretty straightforward. Appreciate the advice.
 
OK, a new twist...

I decided to install the fuselage harness and of course none of the connectors will fit through the holes in the ribs/spar/etc. I assume I need to remove all of these connectors-including the LEMO/headphone/control stick connectors????

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Brian, I am a little suprised that you would have to remove any Molex connector to get the harness where it needs to be. The one that is a complete nightmare is where they branch off and go to the control sticks. If I had to do over again, I would cut those off and rewire them after they are in position. As far as the rest of it, I did not have to remove any connectors. FYI….
 
Deep breath Brian, Deep breath.
All electrical connectors come apart very easily with the proper tools. The hard part is putting them back in the proper positions afterwards.
You must have a diagram from Stein to work from.
 
Typically the harness does not go “through” the snap bushing or the snap bushing holder. The harness is pinched down gently until it can feed into the open side of the holder. Then the split snap bushing is put over the wire bundle and the bushing is pushed into place until it locks in. If you already knew this - disregard.
 
OK, I figured it out.

I went back out to the hangar and looked again at the route the fuselage harness wires take and I think they go through the tabs shown below rather than the typical holes in the ribs. If that is the case, I won't need to remove the Molex connectors from the harness.

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Typically the harness does not go “through” the snap bushing or the snap bushing holder. The harness is pinched down gently until it can feed into the open side of the holder...
Yep! That's what I just learned. I think the harness will go through the snap bushing tab (see photo in previous post) which has an open side. If so, problem solved. I'll confirm tomorrow when I'm thinking clearly.
 
FWIW I don't have a problem with the Molex connectors, either standard or micro-fit. If you use the correct tools I think they work fine. I you don't have the correct tools, any connector system becomes a nightmare. The tools you need are not expensive either. (BTW, I wouldn't have picked the Molex connectors myself if I were designing the harness; but since someone else did, I'm happy to live with them to reduce build time etc. My choice would have been CPCs...)

Also, I don't think modifying the Stein/Van's harnesses is a specially big chore. I've already had to change the WH-00057 to switch to a Artex 345 ELT and to replace the two white wires with correct length ones. Each mod required removing/replacing contacts, adding/changing/running wire, etc. Changing any harness is a PITA, but it's something you'll do a fair amount with experimental aircraft.

Just a contrarian opinion... Not saying the other folks are wrong.
 
I'm just finishing up my wiring in my -4. I did my own harness. Because the 4 has wing stub spars that plug in rather than a spar carry through structure the wiring has to be routed up and over. If I had to do it over again the one thing I would do different is to do detailed drawings - a map if you will. I just added each separate circuit as I went. I got it in the end, after considerable tail chasing and redoing. The other thing I would do if I did it again is to leave more slack in the wires instead of making them the precise length. Maybe this will help someone.
 
Got my system with fuselage harness from Advanced Flight Systems. Empennage was attached. Was worried about the molex connectors through the spar but they went fine. Just need to think about the L-R routing to keep them as organized as possible. Worked from rear forward when final securing them. Also forgot to route the headset jacks from front to back before doing snap bushings…cost about two hours. I used the optional console so I didn’t need to make a 90 turn up to the avionics bay. Made things much easier.
 

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I’m doing the same, but a little different. I’ve got tail done, fuse was a qb, and mostly done, and I’m doing everything I can before big join. So far it’s been easier to access, but as of this week with the avionics and harnesses laying about, and the learning curve is steep. On the 125 harness, only issue spot have had is the route to the sticks, those connectors don’t seem to fit holes, but I stopped and ran everything else today. I’ll come back to those.
 
I’m doing the same, but a little different. I’ve got tail done, fuse was a qb, and mostly done, and I’m doing everything I can before big join. So far it’s been easier to access, but as of this week with the avionics and harnesses laying about, and the learning curve is steep. On the 125 harness, only issue spot have had is the route to the sticks, those connectors don’t seem to fit holes, but I stopped and ran everything else today. I’ll come back to those.
Cut off the molex plugs, route the bare wires, then use dsubs to connect to the stick. I ended up removing the molex plugs on the pilot side stick due to intermittent molex pin faults. BTW -Stein hates molex plugs, too, but installs them at Van’s request.
 
Update:
I was able to route the rear harness wires through the snap bushing tabs that have an open side (post #14). That was easy! But, I had to remove the forward elevator push rod and idler arm bracket in order to get the main harness connector past the spar and into the tunnel.

View attachment 74799

I'm also now having to remove additional material from the holes in the cover ribs (see below) so the control stick connector will fit through.

For those just starting on the fuselage, when you get to the bulkhead assembly on page 25-05, I would recommend enlarging the holes shown below if you plan to use the Stein fuselage harness. If you don't, you won't be able to route the control stick connector through the "cover" ribs. I'm trying to enlarge these holes now and it's NOT FUN.


View attachment 74798
For the stick connector, my ribs have the notches, it looks like maybe the connector goes through sideways? I've not tried yet, I'll report back.

I ran mine before the pushrods, so glad that it worked out and didn't have to take out later.
 
For the stick connector, my ribs have the notches,
Mine have a notch as well but it's only on one side of the hole and the opening isn't wide enough even with the notch for the connector that was supplied with my harness.
 
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I'm pretty much done with the first three kits and waiting for the Finish kit. I have not installed the interior yet and I haven't attached the tail pieces (HS, VS, rudder, etc.). I have the Stein fuselage wiring harness that I bought last summer sitting on a shelf. Is this a good time to install it?

Sorry for the rookie question. First time builder here.
If you have the time,,,, build a rotisserie and do some painting while you wait , this was a game changer on my second rodeo !
 

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Mine have a notch as well but it's only on one side of the hole and the opening isn't wide enough even with the notch for the connector that was supplied with my harness.
I just tried, wires at the back of the connector in the notch, connector sideways, and it will get through. It’s tight, but does make it. I have the stein harness as well, and I don’t remember getting anything off norm for my control stick controls. It was hard to take a picture, this is the first and second hole from the center, the connector has to basically be parallel to the hole, and the wires are bending (like 87 degrees) through the notch. The middle picture is the connector in the hole about halfway.

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I just tried, wires at the back of the connector in the notch, connector sideways, and it will get through.
Good job Brian! I clearly have 2 dimensional thinking. Unlike me, I suspect you'll have no trouble getting the large right harness plug through the side fuselage skin.
 
Good job Brian! I clearly have 2 dimensional thinking. Unlike me, I suspect you'll have no trouble getting the large right harness plug through the side fuselage skin.
Haha no I didn’t have an issue with those, should I ask, or just let that be…

I am trying to figure out avionics box mounting and stacking, and that my go around and co monitor reset buttons don’t come off from the back, little pieces fall out and you have to get new ones!
 
Well, I am glad to find this thread! I have just about finished installing the wire harness, antenna wires, pitot-static tubing to the backup EFIS (a G5) and I’m routing the harness for the control sticks. What a bear. It is extremely difficult to get my hands where they need to be to manipulate the connector from the center tunnel through the ribs.

For those who see this later consider this approach: ROUTE THE WIRE HARNESS FOR THE CONTROL STICK FROM THE CENTER TUNNEL TO THE OUTER RIBS BEFORE YOU INSTALL THE CONTROLS OR THE FUEL SYSTEM, ETC. Basically do it as soon as you get the fuse assembled.

I am not confident I am going to get this done per plan. I may be calling the factory tomorrow.
 
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