Pass-Through Connector / Housing Q for Engineering and Fabrication Folk (1 Viewer)

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jaymar

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Best Way To Run Wires From Roof Rack Into Cabin

(^Alternate title for searches.)

And others who in general have forgotten more about this stuff than I'll ever know...

Can you think of a fitting that meets the following needs? I'm thinking aerospace or marine applications, maybe...

Pass-through from dry interior to exposed exterior (bringing roof rack wiring inside).
Waterproof seals inside and out.
Exterior portion waterproof when closed (probably screw-type closure).
Exterior portion is fat enough to house a large computer mouse cut in half.
The pass-through portion can (and probably should) be thinner than the fat portion just mentioned; maybe the width of a finger or two.
Maybe a gland nut on the interior--in addition to (and below) the sealing fastener.
Flat or domed top cap.

So the outside is basically a small cup with a screw-on lid, and a smaller hole in the bottom that goes through to the interior. Ideally it can take a hit without ripping out, tearing metal, or breaking the waterproof seal.

Anything come to mind?

SHORTCUT: Many workable approaches suggested in this thread (and thanks to all!). To my mind, this is looking like the best solution (for me; no hole in roof). Thanks to @TomH for the link. Those of you new to this thread might just take a look at that--and if it seems to fit your bill, then pick up at Post #35...


Then there's this guy...


Or just cruise through the whole thing for other ideas...
 
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I'm gonna run at least 7 lights on a rack. The wiring needs to get inside. I want to be able to remove the rack with the lights still mounted. So what I come up with is, the connectors all sit in that cup on the roof, which will have two caps: one with a water-tight wiring pass-through, one without. When I want to pull the rack, I remove the pass-through cap, disconnect the wires, put the solid cap on and that's it. The truck-side connectors remain inside the cup. Reverse it to put the rack back on.

I don't WANT to put a hole in the roof, but like other options less: running to snorkel is too exposed and tempting to hands and branches; running it in by the top of the side vent is also exposed, and will channel water directly to the pass-through hole; and running the wires over the rear hatch weatherseal just seems like a bad idea, mashing the wires every time it's used...
 
Alternatively, get a good weather tire grommet to handle passing through the wires. Then for when the rack is removed, have a duplicate rack side connector that acts as a cap to the plugs. This is what I did for a customer with 10 lights up top, each pair on separate controls
 
Alternatively, get a good weather tire grommet to handle passing through the wires. Then for when the rack is removed, have a duplicate rack side connector that acts as a cap to the plugs. This is what I did for a customer with 10 lights up top, each pair on separate controls
Jus looked up tire grommet. You can make that watertight? So you pull the wires inside when the rack is off and plug the hole, or you put the dead connectors on the ends and leave the wires on the roof? I'm not clear on this. Did you take pics of the setup, by any chance?
 
Jus looked up tire grommet. You can make that watertight? So you pull the wires inside when the rack is off and plug the hole, or you put the dead connectors on the ends and leave the wires on the roof? I'm not clear on this. Did you take pics of the setup, by any chance?
That was a typo, meant to say weather tite grommet. I didn't get great pics but I'd do something similar to the grommet where the engine harness goes through the firewall, how the grommet has a little tail. You can even overlap heat shrink on the end of the tail for a really tight fit. Then when the rack comes off, the connection is undone and the vehicle side wires stay in place. The pins are protected by the dummy connector that takes the place of the rack side connector
 
That was a typo, meant to say weather tite grommet. I didn't get great pics but I'd do something similar to the grommet where the engine harness goes through the firewall, how the grommet has a little tail. You can even overlap heat shrink on the end of the tail for a really tight fit. Then when the rack comes off, the connection is undone and the vehicle side wires stay in place. The pins are protected by the dummy connector that takes the place of the rack side connector
I love to see pics of what you have… Personally not fond of wires visible on the roof (if that’s what you’re saying?) as some jerk might just give them a jerk. Guess it depends on your neighborhood. But I wonder if there’s a middle ground. A tall weathertight grommet for example, that has enough room to stuff the plugged connector ends inside the donut. Still need some kind of with a tight seal on top, and also keep the wire ends from pulling away. You’re obviously more familiar with these things than I am. Does anything come to mind?
 
What would be wrong with leaving the connectors exposed when unplugged. Just squirt a little electro grease in the ends....

Batch-6-Funny-LED-Light-Bar-Memes-5_3f2c1a44-233e-468e-a85e-bcd74ec60a87.jpg
 
@leonard_nemoy said: "What would be wrong with leaving the connectors exposed when unplugged. Just squirt a little electro grease in the ends...."

I don't just want them protected; I want them out of sight. I kinda like this rack setup, but maybe with the lights tucked back under the rack for a lower profile... :cool:

JR Lights Off.jpg

JR Lighs On.jpg
 
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Roxtec makes a thing, they use it on submarines or something, maybe a bit overkill for what your doing
If I didn't want overkill, I'd drive something else. With better mileage. And faster. :steer:
 
Electrical Plugs

McMaster-Carr - https://www.mcmaster.com/electrical-plugs/mil-spec-screw-together-connectors-7

Would something like this work? They have caps to cover the plug when the rack is off.

Sorry missed the whole no hole in the roof part lol
Thanks for the link, but I really don't like those for this application. Makes the wiring useless for anything else, requires soldering which can be fragile; if water does get in, it'll hit every connection and not just one. I'm looking for some kind of housing that standard connectors can rest inside of, with wires going out both sides...
 
I was going to suggest Deutsch panel mounts in their DT or DTP series, but those aluminum body connectors from mcmaster are astonishingly cheap even though they have a cast aluminum body.
Edit: saw your response Jaymar, the tricky thing is there's no good way to seal the wires when going into a housing like that aside from the individual wire seals found on the panel mount connectors. At least the Deutsches are crimp connectors and more generic, but more holes in the roof is the last thing I'd want.
 
If you were willing to go with the Deutsch connectors, itd be a lengthy run of wire but from the rack all the way down to the undercarriage between the body and the tailgate seal (where the gas struts are) and have a flush mount plug running into the fuel filler area inside the cab. Out of sight, easy to seal, wouldn't know it's there with the rack off.
 
If you were willing to go with the Deutsch connectors, itd be a lengthy run of wire but from the rack all the way down to the undercarriage between the body and the tailgate seal (where the gas struts are) and have a flush mount plug running into the fuel filler area inside the cab. Out of sight, easy to seal, wouldn't know it's there with the rack off.
Help me out here--you're saying run the wires between the top edge of the hatch and the roof (so pretty much invisible unless you’re tall) then down the side of the hatch and tailgate--and then, where? Where's the flush-mount? So the ‘long tail’ is connected to the rack, right?

Also--I had discarded the notion of running over the hatch seal because it seems to me the hatch action pushing on those wires will eventually chafe the insulation off or break the wires (and deform the weatherstripping until water comes in. Do you think this concern unfounded?

I was thinking to bring the wires into a sPOD on Joey's QPM. As to the DS cubby by the fuel filler neck--what are the chances of fuel vapors escaping into that space?

Oh, lastly--why would I need the Deutsch connectors to make that work?
 
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Bro, your seriously over thinking this....... there are literally millions of vehicles driving around with aftermarket lights all over the vehicles and roof rack and none of them needed anything like what you are looking for.

The following is pretty much industry standard according to my sources.

1. Drill a hole in the roof.
2. Run the wires through and add high quality connectors.
3. Silicone the s*** out of the wires and the hole to seal it up.
4. Install the lights and connect them.
5. When you want to remove the rack disconnect the connectors and fill the ends with di-electric grease if your really worried about getting water in the connectors.

If your rig is so nice that you think a small hole in the roof will ruin it than you have no business adding a roof rack and or any other mods.

If your just worried about people seeing the ugly silicone splooged hole on the roof than you need more lift and bigger tires.

Just my .2 cents
 
If your just worried about people seeing the ugly silicone splooged hole on the roof than you need more lift and bigger tires.
:rofl: Funny. But...let's say Joey wanted to light up his life with a part-time roof rack. "Industry standard" would be right out the window...
 
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Help me out here--you're saying run the wires between the top edge of the hatch and the roof (so pretty much invisible unless you’re tall) then down the side of the hatch and tailgate--and then, where? Where's the flush-mount? So the ‘long tail’ is connected to the rack, right?

Also--I had discarded the notion of running over the hatch seal because it seems to me the hatch action pushing on those wires will eventually chafe the insulation off or break the wires. Do you think this concern unfounded?

I was thinking to bring the wires into a sPOD on Joey's QPM. As to the DS cubby by the fuel filler neck--what are the chances of fuel vapors escaping into that space?

Oh, lastly--why would I need the Deutsch connectors to make that work?
Yep, long tail to rack. So from the back of the rack the loom would run between the sheet metal of the body and the upper tailgate into the recess where the gas struts live, never passing into the cabin or over any seals. Keep going down, past the hinges for the lower tail gate so it's behind the rear bumper, and then down along the chassis and up to the bottom of the shell to a flush mount. Whichever side of the car you choose I guess, it's just the filler side interior panel has the access door for the jack and tools already. Exactly what leonard_nemoy said just drilled elsewhere.

Disconnect the harness, fish the harness up through the bumper and throw it up onto the rack, remove, happy days.

I ran my rack wiring the same way but drilled into the cab above the gas struts, never had an issue with the wires or insulation. Wrap em in some fabric tape if you're worried about the paint.

Doesn't have to be Deutsch I guess, anything like this:

When it's removed:
 
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Yep, long tail to rack. So from the back of the rack the loom would run between the sheet metal of the body and the upper tailgate into the recess where the gas struts live, never passing into the cabin or over any seals. Keep going down, past the hinges for the lower tail gate so it's behind the rear bumper, and then down along the chassis and up to the bottom of the shell to a flush mount. Whichever side of the car you choose I guess, it's just the filler side interior panel has the access door for the jack and tools already. Exactly what leonard_nemoy said just drilled elsewhere.

Disconnect the harness, fish the harness up through the bumper and throw it up onto the rack, remove, happy days.

I ran my rack wiring the same way but drilled into the cab above the gas struts, never had an issue with the wires or insulation. Wrap em in some fabric tape if you're worried about the paint.

Doesn't have to be Deutsch I guess, anything like this:

When it's removed:
Thanks! I'll have to take a look at that in daylight. Second link above is dead.
 

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