I’m going to fish cable (for cable TV) through the walls of a home built in the ’40s that doesn’t have drywall, it’s actual plaster. There is no access beneath the floor but the attic is unfinished. Any advice on the best way to fish the cable? I’ve read a few articles that suggest 1/2″ or 3/4″ polybutylene or PEX is better than a fish tape because it’s more rigid and won’t get snagged as easily as the tape. Also, any tips on mounting the boxes in plaster as opposed to drywall? Thanks in advance for any advice you can provide.
Darge
Replies
Sounds like an easy one..... Normally I would just use a 1/4" fish tape but a small chain may work real nice for a straight drop.
There is a box we use called "easy boxes" that have wings to hold the box to the plaster (between studs) usually I just use a regular box and mount it on a stud after careful cuttting.
bake
Bake,
Thanks for the tip. In your experience are there many obstructions behind the older pre-drywall plaster walls?
Darge
I suggest matching the box height with the rest of the house. But if you are doing baseboard height boxes, be prepared for the "rubble" of plaster bits at the bottom of the bay.
The chain technique works well. A wand magnet is a great way of hooking the chain.Jake Gulick
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CarriageHouse Design
Black Rock, CT
Do you have a stud finder? If not, don't get the panasonic as the one I bought doesn't work in plaster walls. The Zerco (sp?) one with "deep scan" at HD works pretty well. I like to center boxes between studs just to be safe. Once I locate a suitable spot, I also do a vertical scan to look for horizontal obstructions. These will be more common near windows and doors, but I found 3 spread out over a 3 ft section which were a pain in the butt. And while you are at it, why not drop some cat3 or Cat5 in case you ever want to put in a phone or computer jack. Wire is cheap. Also, drop a piece of twine with the coax so you can easily pull new wire into the box.
I hit a lot of fire blocking, and diagonal bracing more than once. Have fun
If the walls have no insulation, common to this time period, I would go with chain from the attic and a short hook from within. Chain, I like welded sash chain with something like a 1/2" by 1/4" links, flows well, doesn't hold a kink and is tremendously strong strong, something over 100 lbs break.
I would use a Caddy, a brand name. A galvanized steel plate with fold out wings that accepts a cover plate commonly used for low voltage and communications wiring. You cut a hole using the plate as a guide. This allows a hand hole that is still easily covered with a standard plate.
If there is insulation I would go with a short length of electrical fish tape. The man in the attic, using light tapping as a guide finds the plate over top of where the outlet will go. He, or she, then drills a hole. A cordless will work but I have found a good sharp auger in a brace to be as fast without the risk of running out of battery and having to climb out and back in.
Once the hole is drilled, if there is no insulation the person looking into the outlet should see sawdust come down but if they fell asleep and missed it stomp a bit to wake them and shine a light down the hole while they look. Failing to get into the same stud space can lead to frustration so get it right the first time.
If no insulation drop the chain and wiggle it slightly up and down. An hook bent into a piece of #12 that touches the moving chain will transmit a distinctive feel. Communicate. If you feel it contact sing out with a clear "touch". That way both sides know your getting close. Hook the chain. Sometimes inserting your hand and grabbing the chain is easiest, particularly in insulation.
In insulation the man below must listen and watch closely for signs of the tape. I use a 15' length cut from a longer tape. Shoving your hand in and pushing the insulation down the bay to clear an area can help. Hook of grab the tape when possible. Sometimes reinserting the tape is helpful. Rearrange the insulation before mounting the Caddy box.
If you hit fire blocking like Sphere then I would suggest getting a long flex bit, You can drill your way through. This company has a lot of tools for making wire fishing easier. http://www.lsdinc.com/
Edited to add this link that shows their method of doing it. You might have to copy and paste the text into your address bar.
http://www.lsdinc.com/lsdinccgi/search.cgi?user_id=77737&1_option=2&1=FIA&database=data/Dbase3.txt&template=templateapp.html&output_number=10
Edited 12/14/2003 11:06:12 AM ET by Gunner
Edited 12/14/2003 11:06:51 AM ET by Gunner
For a glass-fibre insulated bay, I've used a length of 5/8" dowel, sharpened and with a hole drilled at one end (like a needle). Fasten a piece of string line to the sharp end and push this down through a hole drilled in the top plate (working from the attic). Helper can attach coax or elect. wire to string, then you pull up. Works fine if you're alone: just push the dowel down a known distance and it will be waiting for you by the opening you've cut in the plaster.
I use a sectional fiberglass fish rod. Comes in 3 or 4 foot sections that screw together. Drill a hole, push in a section, screw on another, keep going until you get where you want. Insulated so you don't get zapped if you hit something live. Stiff enough so you can feel where you're going or push through insulation. Easy to tell how far you went so you can figure if you hit blocking. Even some of the home centers sell them now. Not super cheap, but worth it if you're going to do a couple jobs. Maybe $30.
sounds like a chimney cleaning rod...GREAT idea..to think I had 8 sections all these years and would never have thought to do that.
Basically the same thing, but the ones made for electrical work are thinner and have a selction of screw-on tips for stuff. Magnets, hooks, pointy ends. They bend around stuff easier. If you're just doing straight pulls, the chimney cleaning rods should work OK.
r e-
I use a sectional fiberglass fish rod. Comes in 3 or 4 foot sections that screw together.
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I agree 100%.
They are available at any good electrical supply house.
Home Dump or Lowes does not stock them in our area.
Invested in a set that cost around $80. (I am not an electrician.)
Has several different length of sections that can be screwed together - this helps when you need to feed the rods through spaces that cannot accomodate a full-length rod.
There is also a tip with a hole for looping a string or whatever.
In addition to fishtape, the electricians' fiberglass rods are a must-have that saves a lot of time.
As for actually cutting the hole in the plaster, I recomend using a 4 1/2" grinder with a diamond blade. Plaster is a form of white grinding wheel and steel doesn't last cutting thru it.
As for the blocking, fire stops [actually "electrician stops"], a .45 caliber automatic will quickly, easily make a nice, perfectly round hole for your cables. Use the special "slug punching" ammo.
~Peter
can't cha make a series of closly spaced holes with the same .45? then just kinda pry out the fiddly bits? This is like the thread I had about wireless receptacles..why not wire less CATV as well? Sparkies can have more free time for fishin' or what ever? <g>
Who would use a 45 to punch holes? Highly inefficient. It being deer season and all, most everybody carries a 12-gauge loaded with slugs. One shot gives a nice clean wireway from attic to cellar and then some. I know somebody who actually did that. Unfortunately it was through the middle of the dining room and bedroom floor. "I didn't think it was loaded." Probably the third most common southern phrase. Right after "Hey y'all, watch this" and "you want grits with that, hon?".
The guy I knew who did that had his head in the way..brains on the trailer cieling..Hell, I sold him the trailer. Above the MANSON/NIXON line tho'
Considering that it's only one hole, I don't think the .45 would be terribly inefficient. For jobs requiring a large number of holes, I automate and use my .50 cal. machine gun [the tool of many uses].
I was thinking of portability and the situation in the attic where you don't have much room between the top plate and the roof.
~Peter
Don't fight the attic space. Just go out onto the roof and fire straight down. The hole in the roof you can patch with a dab of tar.
Even with Bosch aggressor blades, expect about 3 boxes per blade. Such a shame too. The rest of the blade is perfect except for a 3/4" section in the middle which is honed flat. They should make blades like box knives where you can just snap off the dull part and keep going. ;-)
Actually that is exactly what I have been known to do with sawsall blades. For rough work I have been known to duct tape a piece of 2by to the saws foot at maximum extension. I saw into the scrap block so it stabilizes the blade a bit. Once the tip of the blade is shot I retract the foot an inch or so to get fresh teeth.
After a couple of times doing this, when the blade is now extended some distance past the work, I take off the block of wood and, using a pair of Kleins, I break of the first inches of the blade so it doesn't get in the way.
I find I can, make sure you only do this with the 2000 Klein models or other pliers with highly hardened knives, make a small groove with the cutters, don't try to go all the way through just a small indented groove perpendicular to the toothed edge, and snap the worn area off. Wear safety glasses as small splinters sometimes fly a considerable distance.
Repeating this you can get a lot more wear out of a long blade. often wearing all the teeth off. Of course you could also tell your boss to get off his cheap, lazy butt and buy more blades as if he knew what he was doing.
I am the boss, and I prefer mellow and thrifty to lazy and cheap. ;-) If I were smart, I'd make a holder so I could use the good 2" of blade for sawing trim and drywall.
As for Kleins, my neighbor was struggling tonight to get the license plate off a car he had just sold. Screw was stripped and the edges bent as well. But gripping it with a pair of heavy Kleins and two hands got enough grip where it could be twisted free. Sometimes a hard bolt just needs a harder plier.
I have always had exellent luck cutting plaster board with a carbide grit impregnated sawzall blade. The one that I recently bought was made by Remington. If cutting plaster with wood lath( not likely in 1940's) Do not use a sawzall, the vibration will break the keys and cause massive problems. Like someone else said use diamond blade in circ saw or grinder then cut lath with old circ saw blade or jig saw if your carefull. Good luck. Jay
I use a diamond blade hand grout saw to cut in for the boxes. For those little 2" x 4" holes, the energy required is so small that it's easier than messing with cords or batteries. And it lets you see what you're doing and get all the way into the square corners without overcutting. With a power tool, you burn the diamond blade against the lath, but with the hand saw, you can feel exactly where to stop. Break out the plaster and cut the wood with your recip or whatever. The wood cutting blades will last OK, especially if you wire brush the remaining plaster off first.
-- J.S.
Hi Darge
Think outside of the box! There are many WiFi i.e. wireless connections for TV, computers etc. Go to your local electronics store and check out the wireless connections. Had the same problem re a 35 foot wall and a light switch and now have a battery powered light switch. Couldn't find a 35 foot drill! LOL
Mac
"As for the blocking, fire stops [actually "electrician stops"], a .45 caliber automatic will quickly, easily make a nice, perfectly round hole for your cables. Use the special "slug punching" ammo."
"can't cha make a series of closly spaced holes with the same .45?"
"most everybody carries a 12-gauge loaded with slugs. One shot gives a nice clean wireway from attic to cellar and then some."
"Considering that it's only one hole, I don't think the .45 would be terribly inefficient. For jobs requiring a large number of holes, I automate and use my .50 cal. machine gun [the tool of many uses]."
"Don't fight the attic space. Just go out onto the roof and fire straight down. The hole in the roof you can patch with a dab of tar."
Geez, you guys trying to make the plumbers with their sawzalls look good??
Rich Beckman
Another day, another tool.
Re: "Geez, you guys trying to make the plumbers with their sawzalls look good??"
In the spirit of the season I was trying to give our friends with the world famous butt cracks a break. Saw a plumber the other day and neither his truck nor his boat were new so times must be hard. How the mighty have fallen. I was profoundly tempted to start a charity to help the fellows out. So lets all go out there and give our local plumbers a hug.