Getting ready to re-wire the trailer

[JASinIL2006]

I'm getting ready to re-wire my single axle trailer. It is build with tube construction (2'x3" tube, I think) and one of my tasks is to drill holes in the side of the frame near the axles for my electric brake wires.

Currently the wires run inside the tubes from the tongue of the trailer all the way to the very back, where they exit. The wires then travel back to the axles in some thin tubing (hydraulic brake line tubing) that I clamped to the inside of the frame. I really don't like this set up, as the tubing takes a beating whenever I jack up the trailer or back it into an overgrown parking spot at out lake cabin.

I plan to drill holes into side of the frame, install rubber grommets to protect the wires, and to allow the wires to connect to the brakes.

My question: what do I need to drill through the frame? I've not tried drilling larger holes (I'm shooting for 1/4"-3/8" holes to give me clearance for the wires) into the frame. I'm assuming I start small (e.g., 1/8" drill bit) and work up, but is there any trick to it? Any special bits that make it easier? High speed drilling? Low speed? Is it better to drill dry or use some sort of cutting oil?

I'm assuming that one hole on each side of my trailer frame won't weaken it. Is that a safe assumption?

Thanks, as always, for your thoughts.

Jim

 

[ahicks]

1/8" pilot hole is a good plan. From there you can go directly to the size you want without further steps.

I would caution you though, regarding what the rust on the inside of steel tubing (frame and axle) is capable of doing to a wire harness. Have seen enough trouble where I would not recommend it. It's caused some of the worst erratic shorts you can imagine. -Al

 

[matt167]

Many hotrodders will weld steel tubes in place to chase the wire through 2x3 tubing. There are also bolt in chases where the tube is held in with nuts on each side

 

[ahicks]

You could do a lot worse than some type of plastic tubing clamped (not tie wrapped) to the inside of the frame.

 

[Captain Caveman]

I wouldn't be scared away from your plan. Use a standard metal drill bit, drill the hole, and then paint it. Make sure that you paint it inside and out to avoid rust. Put in your grommet and be happy.

 

[Scott Danforth]

Drill a 1/2" hole on the tube centerline and use a rubber grommet for the wires to come out of the frame tubing....... Just like factory runs on most trailers

 

[Grub54891]

And no matter what, run that ground wire directly to each light, don't depend in the trailer frame to do it for you.

 

[Scott Danforth]

And no matter what, run that ground wire directly to each light, don't depend in the trailer frame to do it for you.

This is great advice

 

[JASinIL2006]

Thanks for all the thoughts on this. I do plan to run ground wires to all fixtures, rather than using the frame as a ground. I'll be wiring using the 'star' patterns so that if something happens to the brake connections on one side, the other side's brakes still will work.

I've thought about installing tubing (e.g., PVC conduit) on the outside of the frame tubes, but I'm not particularly fond of how it looks. My trailer would have a lot of places where I'd have to transition from PVC conduit to some sort of ribbed sleeving to get around cross-members, etc., and I think those places would make the wiring more vulnerable than if it were inside the frame. I guess this is a long-winded way of saying I'm leaning toward still using the frame tube for the wiring. I'll use as boroscope camera to look inside the tubes and if they look really rough, I can always chase the wires thru corrugated sleeving inside the tubes. The current lights all have their wiring run inside the frame and they've been OK.

If I run the wires inside the frame and drill 1/2" holes as Scott Danforth suggests, do I really need to just drill a 1/8" hole and then jump up to a 1/2" bit?

I'm planning to make my electrical connections using waterproof solder-seal connectors. Any problems with using those for this application?

 

[gm280]

So many good ideas and I second the idea of running individual wires for ALL grounds. But you can also use the trailer frame as ground too.Then you will never ever have a ground issue with both ideas.

My only problem with my trailer is SQUIRRELS! Yes, those pesky critters love to chew through any exposed wire(s). They have even chewed the red lens plate on the trailer. So I now have to do some rewiring on my rewired trailer. And the only exposed wires I have are small exposed wires from the tubings to the lights themselves. A mere 6 inches or so. But they also chew through the chain-link fence straps at the top rail as well. The straps are aluminum and I have replace them three times now from them chewing trough them.

So I think you will not have any problems with the great advice given... Just make sure to use grommets to avoid rub through!

 

[JASinIL2006]

Grommets I have! I don't recall when I got them (maybe when I first contemplated this re-wiring project a couple years ago?), but I have big box of grommets of assorted sizes. No rub-through on my wires!

 

[Scott Danforth]

Only cure for squirrels is a 5mm pellet gun and a silencer.

Center punch the hole, drill the 1/8 pilot if you want, then a 1/2" drill bit

 

[gsh]

When I ran my electrical for my trailer I used wire that had all 4 conductors in one sheath then covered the whole thing with heat shrink. You can buy heat shrink in 10 foot rolls and this adds one more layer of insulation to prevent chafing problems.

Where the wire ran through the metal tube I used rubber grommets from Ace Hardware.

I didn't run a seperate ground wire and never have any problems.

Also, when I made my connections I got the cheap plastic coated crimp connectors, cut off the plastic and used them that way. Heat shrink over the wire, crimp the trailer wire to the wire from the light, then use a torch style lighter to heat the connector enough to take solder. After it cools, use liquid tape to coat the connection and let it set up for a minute. Once it's starting to dry but still soft, slide the heat shrink up and over using a slight twisting motion and use a heat gun to shrink it down.

The crimp creates a temporary connection to make the soldering easier. The solder provides a solid connection that won't come loose, The liquid tape under the heat shrink creates a watertight connection.

Finally, I used plastic zip ties to fasten the wire to something so it doesn't flop around. and break.

As for the brakes, I would strongly suggest you don't wire them so that one brake activates if the other one fails. This can cause a situation where the trailer pulls to one side and slides off the road or into oncoming traffic. Especially if you are on a slick road such as rain or frost.

Either have both brakes or none.

 

[guy48065]

Where do you plan to drill the holes?
I would suggest the bottom for drainage.
On one of my trailers I had intermittent electrical problems until I removed all lights & markers & found water inside the frame tubing that corroded wire splices. This particular frame had NO drainage anywhere so whatever got in just stayed there.

 

[JASinIL2006]

Where do you plan to drill the holes?
I would suggest the bottom for drainage.
On one of my trailers I had intermittent electrical problems until I removed all lights & markers & found water inside the frame tubing that corroded wire splices. This particular frame had NO drainage anywhere so whatever got in just stayed there.

Everything I’ve read said not to drill in the top or bottom because it will weaken the frame more than a hole centered on the side.

 

[dingbat]

I'm planning to make my electrical connections using waterproof solder-seal connectors. Any problems with using those for this application?

Junk....wouldn’t recommend them to a competitor.....

Not a fan of soldering in this application. Stripping the wires. Cleaning them, Apply resin, solder then clean connection with alcohol and apply a protective cover. Far too labor intensive for what it’s worth.

Easier to use the connectors below with quality crimpers.
https://www.ancorproducts.com/en/309125

Make sure to use tinned wires with PVC jackets. I ran 16/3 bilge cable down each rail of the trailer. The cheap wire used in the light kits is junk

 

[JASinIL2006]

I was referring to these connectors.

 

[dingbat]

I was referring to these connectors.

So was I...there are no short cuts to proper wire prep, wire wrap and soldering procedures.

Wires are to be stripped, cleaned (chemically) and tinned prior to final assembly. Upon assembly, the connection is heated to a temp to facilitate not only the flow of solder into the joint, but to allow the resin (acid) to do its job and float any contamination in the joint to the surface for cleaning.

These connectors accomplish neither....

https://m.youtube.com/watch?v=cSa-wDEdABc

Most specifications mandate crimp connections on high flex, high vibration environments anyhow

 

[guy48065]

Those solder rings are good enough for military and OEM marine use. What's the issue here?

 

[JASinIL2006]

I'm reading a bunch of stuff online re: the all-in-one connectors. Some of it (like the link posted by dingbat ) are not very positive, others talk about how those connectors have been in use in aeronautical and marine apps for decades. Seems the quality of the seal comes down, in part, to how focused the heat source is. Diffused heat sources, like a heat gun without a reducer, don't get the solder and wire hot enough to allow the solder to penetrate the wire. Sounds like a propane or butane torch might do better.

I've already got some of these connectors, so I'm going to experiment on some wires and cut them apart after using the connectors to see how well the solder penetrates. My current trailer has all kinds of even more hinky connectors that have held up for years, so I'm not super worried about this. But I am curious now....

FYI, the holes were drilled without any problem (other than having to work on a creeper under the trailer). I drilled a 1/8" hole, followed by a 1/2" bit, using titanium drill bits. Keeping the drill speed down and using plenty of cutting oil seemed to help. Easy peasy.