In this post, I talk about how I pulled an IR cable from my projector to my equipment close through conduit using a pull cord I had left for just such purposes.
Video link for the moving pictures fans:
This started because I bought a Logitech Harmony Companion remote to control my theater. I wrote up a more detailed review elsewhere but the important part to note here is that the Harmony Smart Hub controls devices via wi-fi, bluetooth, and IR. This was critical because my projector is a Panasonic PT-AE8000U which requires IR for control, since it predates any modern smart controls.
The Harmony supports IR out of the box and ships with a “mini blaster” to emit the IR signals. This blaster can control any number of IR capable devices as long as they are sight but I only cared about it supporting one, since my projector is my only device that requires IR.
The mini blaster has a chunky emitter on one end and an 8′ long cord with a jack that resembles a headphone jack that plugs into the Smart Hub. My conduit is 17′ long and when you factor in a few feet more to be usable on each end, well, that 8′ isn’t going to cut it. I was glad to see, then, that that jack that resembles a headphone jack is actually compatible with them and so I just bought a 12′ headphone extension cable and taped them together.
I already had a pull cord left in the conduit going to my projector from when I installed the HDMI cable in the first place. I have a video that describes how to use a vacuum to install that pull cord in the first place, if you care to see that. In any event, I attached one end of the IR cable to that pull cord using electrical tape and then added on a new length of pull cord to that bundle for good measure. I always do that when pulling cable so that there is always a length of pull cord left in each of my conduits in case I want to pull any more cables in the future. You know — like I’m doing right now! Yes, I’m glad that I left one there when I installed the HDMI cable in the first place.
I use a cable lubricant nearly every time I pull cable since I’ve found that it often makes a huge difference. That is, if you have a tiny cable going in a massive conduit than it might not be necessary at all, but in any more tight spaces, it can actually be a requirement. That’s because the conduit walls and any existing cables in the conduit can create a surprising amount of friction which also creates a notable amount of heat. This all will mess with the process of your cable pull quite a bit and if there are any extra impediments like corners and the like then that might be enough to stop the cable pull dead in the water. So yeah, cable lubricants make a big difference.
It had been over a year since I last used my bottle of lube, though, and I didn’t remember if it was supposed to be a liquid or a gel. I vaguely remembered it as a gel, but by this time is was definitely a thin liquid! In hindsight, I should have realized that it had gone bad and just thrown it away on the spot, but in the moment, I decided to at least give it a try.
So I put down a towel over the chairs under the projector conduit to stop any overflow and squirted some of the lube into a bowl. I then essentially soaked the cable and pull cord bundle in the bowl to coat it as best as I could. It felt a little bit slippery, but not as much as I remembered back when it was a gel. Still, I pressed forward.
I attempted to pull the cable through three times. The first was just me and that failed almost immediately. The cable hung up only a few feet in and wouldn’t go any farther. That wasn’t too much of a surprise on its own because I’ve had very sporadic success pulling cable on my own. I’ve found it to be extremely handy to have somebody essentially “pushing” the cable on the other end and agitating it a bit to loosen up any stopping points.
I made sure I had help the next two times. Specifically, my son pulled the cable from the equipment closet while I did the agitating and pushing from the projector end. I needed to be the one by the projector since my son was far too short.
Those attempts also completely failed as the cable got too hung up at some point and refused to budge, no matter what we did.
I suspected that there were three problems.
First, the HDMI cable is one of those “flat” ones which makes it very thin but also means that it’s very wide. I am guessing that the thinner cable bundle I was pulling through was getting wedged between the HDMI cable and the conduit.
Second, the conduit has several sharp turns and since it’s already a fairly tiny conduit, I think my possibly wedged cable bundle couldn’t make it past those corners.
And finally, that lubricant was clearly bad and was doing absolutely nothing to help at all.
A New Perspective
Since the HDMI cable was part of the problem, I decided to pull it entirely out of the conduit and leave only the original pull cord in there. My goal was to pull the HDMI cable and IR cable at the same time so there’s no possibility of them wedging.
I pitched the lube and went to Home Depot for a replacement. While there, I found a new alternative. It is a foam based product that is supposedly so much better than the gel. The gel works by you rubbing the lube on the wires by hand. With the foam, you just spray it inside of the conduit and it expands. You then pull the cable normally through the foam and it auto-lubricates. There’s no mess at all and it lubricates quite a bit of the cable. A very slick idea, if it works!
If we take a step back, though, we can see that there’s a bit of an issue. It starts with that IR cable. Yes, the jack end is very skinny but the blaster end (which needs to be in the theater, obviously) is notably chunkier. Indeed, it is roughly 1-1/2” wide
This is a problem because my projector conduit is only 1-1/4″. Oof. Yeah, the blaster head won’t fit through the conduit at all, thus meaning that I am required to pull from the projector to the equipment closet and not the other way.
As an aside, installing 1-1/4″ conduit to the projector was dumb. I consider 1-1/2″ conduit the absolute bare minimum for theater conduit and that’s literally only if you are only planning on having one cable in there. If there could potentially be more than one, then start at 2″ at a bare minimum and go up from there!
Anyway, so we need to pull from the theater. No big deal, right?
Well, let’s look at the attic just above the projector mount. Note how the conduit doesn’t go directly to the ceiling but actually goes to a backer box. I created this backer box to make sure there wasn’t any sound leakage around the projector mount area.
As a result of the way this was all constructed, though, the conduit only goes to the top of the box. That means there is a space of maybe 10 inches where there is no conduit at all!
No conduit means no place to spray the foam. But since I need to start from that side, how can I work around the lack of conduit to spray my lubricating foam?
What I did was get out a spare pipe to use as a surrogate conduit of sorts. The idea was to run the cable bundle through this pipe pretending that it’s part of the real conduit run. I would then fill this surrogate conduit with the foam and when the cable goes through, it should self lubricate just as well as if the pipe was in the wall or ceiling.
That’s the theory, anyway. I started by threading the pull cord through the surrogate pipe.
Next up, I gathered up the HDMI cable (remember I removed it earlier), IR cable, and new pull cord and attached them inline to the end of the original pull cord.
I shook the foam spray can well and then attached a flexible hose to it. The hose goes into the top of the pipe. There is a chart that says roughly how long you should let it go based on the pipe diameter so I sprayed for that long… but I don’t remember the actual time. A few seconds.
Now for the moment of truth — did it all work?
Yes! It worked fantastically well. The surrogate conduit worked far better than it had a right to and I could see how the cable was thoroughly coated the entire length of the run. The pull itself was the same “me in the theater; my son pulling in the equipment closet” but this time it was all smooth sailing.
The hard part done, I just needed to hook my projector back up. That was pretty straightforward.
I did make one more boneheaded assumption and that was that the IR receiver on the projector was in the translucent section on the side of the face. There are a set of little bulbs there which I somehow thought to be related to IR.
Had I thought about it for even a few more seconds I likely would have realized that an IR receiver doesn’t have any bulbs! Anyway, it turns out that those are emitters for the 3D and have nothing to do with IR. I checked after getting very spotty and inconsistent results in my initial testing. The IR receiver is actually a round circle in the middle of the projector face!
After the fact, then, I went back and just placed the blaster on top of the projector and the reflected IR signals work like a charm.
I do have some lessons learned after this turned out to be more of a pain than I anticipated it would be.
First, that foam lubricant is pretty awesome. The gel worked okay when it was new but it was still very messy and didn’t coat the entire cable. The foam is mess-free and coats everything. Sweet!
Second, 1-1/4″ conduit is simply too small. As I mentioned earlier, that should have been 1-1/2″ at a bare minimum and honestly probably even more than that. The cost difference is negligible and the additional room to maneuver is invaluable.
The Third, which I guess I already knew, is that having a helper when pulling cable makes a big difference. I tend to do most of my theater stuff entirely on my own but this is one area where help really matters.