Fishing Wires/Cables through Walls

[Gooserider]

Sorry for the hijack, but why low voltage box only? I used a metal box and it has openings top and bottom with tons of room for wire/coax to go through.

I understand the kinking issue but is there a problem I need to know about for using a metal box? I am about to close it up and now would be the time.

I don't know of a specific reason NOT to use a metal box, except that the box should NOT be connected to an AC ground (and it is ABSOLUTELY prohibited for AC and Low voltage to be in the same box unless it's divided by a solid partition) Code doesn't (that I know of) absolutely prohibit use of AC boxes, conduit, etc. with low voltage equipment, but it is frowned upon. Part of this is color coding to tell anyone working on the stuff whether it's AC or low voltage, which is why low voltage boxes, etc. are normally orange, while AC stuff is blue.

The problem with any solid back box is clearance for the bend radius, especially on coax type cables - there is BARELY enough room for a proper bend in the full width of standard 2 x 4 wall construction. Bending coax to sharply can cause the inner dielectric to be distorted, and allow the center conductor to get to close to the shield, even though it doesn't short, this will still have a negative impact on the higher frequency transmission characteristics of the line - iow, you get subtle reception problems on the TV...

Kinking and tight bends on CAT5 aren't as catastrophic, but they still aren't good - again that is a wire which has critical design parameters that depend on the exact spacing of the conductors, the differing twist rates of the pairs, and so on. Doing computer grade cabling is fussy if you want to do it properly, as the designs are pushing the limits of the laws of physics in order to get the performance out of the equipment, and deviations from the standards will cause performance issues even though low frequency / DC continuity checks may pass....

Gooserider

 

[johnn]

I love metal boxes, especially for electrical, despite the fact you need to ground them. However the orange boxes with open back are such a "breeze" to work with. All my coax outlet plates have the splice (or what we used to call 81) attached to the plate. No wires hanging out. This set up will cause sharp bends to the coax in an enclosed box. When using open boxes, or at any box for that matter, I use the foam pads you purchase in the wiring dept which creates a decent seal between your face plate and wall. Also I put non setting putty around the pulled wires where they penetrate the header. Tighten her up a little at a time while your opening her up,,,my thoughts anyway. Heck, when you get your house sealed to a certain point, you`ll feel air coming in through the electrical plug, unless you plug it with one of those cheap child proof plastic thingys. (keeps kids from sticking things into outlet)ouch.
3/4 would be my preferred bit size,,,didnt know those wall bits had a hole in the end, (nice),,,
FWIW: Plaster has its own issues,,,one blade for plaster that doesnt dull,,but nor does it cut wood. Instead it wants to burn through the lathe boards, and then you need a spray bottle or a fine tooth blade in a jig saw or sawzall which will want to knock your boards loose from the plaster. Hard to cut a tight hole in any case without taking your time and metal boxes are unforgiving in plaster walls if hole is small.

 

[Gooserider]

Our walls are sheet rock, so mostly no problem, but I did get a Roto-zip tool, which definitely makes life easier... One technique that I did find useful is if you can prop the suction hose for your shop vac next to where you are cutting it minimizes the dust, and makes cleanup easier... If you have an assistant then it really works nice to have one cut while the other follows the tool with the vac.

Gooserider

 

[burntime]

Do you have a chimney or plumbing chase? Easier tehn fishing

 

[Gooserider]

I agree, it is far easier to follow a "stink pipe" or chimney up and down since it's a path that's already established. However note that it is important to keep your cables at least 6" away from a prefab type chimney, or put them in a conduit - I used a couple sections of orange flex conduit to run all my connections from the home node in the basement to the uppermost of my FIVE different attic spaces, and then back down to the outlets in the master bedroom and bath, as well as out to the garage for those outlets and the demarc point connections. (Remember if pulling low voltage through conduit, you are not supposed to pull through more than 90* worth of bends, not counting anything within 6" of the start of the pull...)

Just for fun, I'm attaching a picture of my home node panel in the basement...

The top horizontal item is the 48 port ethernet patch panel, with short cables running to the router-hub (white box) and a second expansion hub (black box next to it.) I also stuck a spare phone up there, mostly used for testing.

The big white square in the center is a 300 pair patch panel for the telephone connections above it are the two local jacks for the two lines I have wired at the panel (All pairs going to the other jacks are punched down on the panel, but aren't necessarily tied to anything) The black box next to the telephone patch panel is the cable modem from Commiecast. It connects to the telephone patch panel, and to the input port on the router-hub.

The two horizontal bars on the bottom are the keystone jack plates for all the cable tv outlets - just out of the picture below is a splitter that sends the comcast connection to one of the jacks for the one TV that we actually use, and the cable modem.

The big bundle coming down the left side of the panel is about 5" in diameter, and contains all the cables running to the different jacks.

Gooserider

 

[johnn]

wow! Thats kinda what I emagined when reading your responses.You really got a handle on that stuff,,,way out of my learning curve.
And yes,,,the shop vac works wonders.

 

[d.n.f.]

I was a fan of plastic boxes until I found one in the house I am in now where the previous owner had somehow stripped out the plastic electrical outlet threads. ??
Pain in the ass to fix.
I figured you can't put high and low voltage in the same box (cable/ethernet). Good to know.

That is quite the picture. Nice set up. Wish my wiring and plumbing was home run. Noice.

 

[Gooserider]

I was a fan of plastic boxes until I found one in the house I am in now where the previous owner had somehow stripped out the plastic electrical outlet threads. ??
Pain in the ass to fix.

I don't know, I've encountered those as well, and didn't find them a big issue - just go with a sheet metal or wood screw the next size up... Actually IMHO metal boxes are harder since you have to get the threads cut for the replacement screw...

I figured you can't put high and low voltage in the same box (cable/ethernet). Good to know.

It's both a safety issue and a signal degradation problem - obviously you don't want to risk putting AC on the low voltage wiring, and you also don't want the low voltage wiring picking up the 60 cycle AC signal either.

It's considered acceptable to have a deep multi-section box with a partition in it that has the AC in one section and the low voltage in the other (you can get the partitions from one of the box makers), or you can get low voltage "extension" boxes that will snap onto the side of an existing box, but really it is better if you can keep everything well separated. A while back I helped a friend run AC and low voltage out to a gazebo in his back yard, we laid two 3/4" NMT plastic conduits underground (one trench, but stayed on the opposite sides of it as much as we could) and ran the AC through one, and the low voltage through the other...

That is quite the picture. Nice set up. Wish my wiring and plumbing was home run. Noice.

Thanks...

Gooserider