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Master Brian
01-07-2009, 10:29 AM
Out of curiousity, what is the main difference besided the material. Why do some prefer metal and others prefer plastic. Is there any safety issues or is it just a matter of personal preferance?? My understanding is the metal ones need to be grounded.

220/221
01-07-2009, 11:41 AM
Plastic boxes are far superior for NM cable wiring simply because the don't conduct electricity.

Plus they are less expensive and easier to install.

Some people think plastic = cheap.

jamiedolan
01-07-2009, 01:58 PM
Out of curiousity, what is the main difference besided the material. Why do some prefer metal and others prefer plastic. Is there any safety issues or is it just a matter of personal preferance?? My understanding is the metal ones need to be grounded.

Most plastic boxes are not rated for exposed work, i.e. concrete walls in the basement. So metal is much easier to use there.

I've had some bad luck with some styles of plastic boxes cracking and breaking when installing them. I am sure some of the plastic boxes are better than others, I would suggest getting the better quality plastic boxes if that is the direction your going.

Jamie

codeone
01-07-2009, 02:01 PM
Out of curiousity, what is the main difference besided the material.* Why do some prefer metal and others prefer plastic.* Is there any safety issues or is it just a matter of personal preferance??* My understanding is the metal ones need to be grounded.

Yes the metal ones do have to be bonded. (grounded)

frenchie
01-07-2009, 04:26 PM
The threaded holes for the screw that hold the device, strip out way more easily on plastic boxes.

220/221
01-07-2009, 05:07 PM
I have never seen or stripped a screw hole on a Carlon blue box.

I have seen some old grey Slater quick clip boxes circa 1980 where the little metal tabs broke completely out and I had to replace about a dozen of them. The Carlon boxes have a hole thru about 3/8" of pliable plastic. You can run drywall screws in ond out of them with ease if you need longer screws. They can't strip because they are not threaded.

codeone
01-07-2009, 07:16 PM
The threaded holes for the screw that hold the device, strip out way more easily on plastic boxes.

What size drill/driver are you using to run the screws in and at what torque setting to do this?

Have seen this complaint quite often. Suggest you use one of the smaller compact drill/drivers with th torqu setting just enough to bottom out the screws.

WV Hillbilly
01-08-2009, 09:08 AM
I have seen light fixture boxes used for & called junction boxes . If installing a box in a ceiling that might have a light fixture or ceiling fan hung on it I always use a metal box . If the box is to be used for a junction box only , either should be fine .

jamiedolan
01-08-2009, 11:22 AM
I have seen light fixture boxes used for & called junction boxes . If installing a box in a ceiling that might have a light fixture or ceiling fan hung on it I always use a metal box . If the box is to be used for a junction box only , either should be fine .


If a plastic box is UL listed as a fixture / junction box, then it is fine to use for either.

Use the correct box where necessary and it is all legal, metal or plastic.


Jamie
*I am pretty sure there are some schd 80 plastic rated for exposed work, but am not positive, I use metal.

WV Hillbilly
01-08-2009, 04:52 PM
I didn't say it wasn't legal to hang a fan or heavy light fixture on a plastic box . I just prefer a metal box for those applications .

hj
01-09-2009, 08:35 AM
quote; Some people think plastic = cheap

So you must be one of the three or four people who do not think that. Would you REALLY hang a fan on a plastic box, unless the mounting bolts were fastened to the structure and not the box?

220/221
01-09-2009, 03:59 PM
So you must be one of the three or four people who do not think that.


Yeah. Me and the other three guys made the decision to install platic boxes in 98% of the houses built since 1980.




Would you REALLY hang a fan on a plastic box, unless the mounting bolts were fastened to the structure and not the box?

Hey, I wasn't the one who changed this to a fan box thread. Try to keep up plumber.:rolleyes:

codeone
01-09-2009, 04:04 PM
is it UL listed for it. If it does it would pass for the weight rating of the box!

Scuba_Dave
01-09-2009, 05:17 PM
I installed one of the heavier duty plastic fan boxes with support in my sunroom. I still didn't like the feel, support
So I ran a 2x4 between the rafters & screwed the box to that
It doesn't budge at all now

I like the deeper plastic boxes - more room
The existing metal boxes in this house were way too small
My basement still has a few larger octagon metal boxes
I installed plastic boxes at the ceiling level or on partition walls
Unfinished basement, I didn't want any boxes down low
We are near a stream & possibility of flooding if heavy rain & the sump pump failed

frenchie
01-10-2009, 10:23 AM
I didn't know rated fan boxes came in plastic.

Huh. Learn something new every day.

chris8796
01-11-2009, 05:53 AM
I prefer metal boxes just for the drywall cutting aspect. The easiest way to install drywall is to cut it with a rotozip or similar while it is screwed to the wall over the boxes. Metal boxes I can cut around perfectly, plastic boxes are touch and go. Since I don't do it often enough to develop a feel for it, I like the metal boxes. I also like them for the other reasons stated too. I still use plastic, especially "old" work boxes, but in general I'd prefer metal.

hj
01-11-2009, 06:36 AM
Yeah. Me and the other three guys made the decision to install platic boxes in 98% of the houses built since 1980.

That was not the question. The question was, WHY did you do it if it was for some reason other than price. AND labor being one factor in the price.

220/221
01-12-2009, 04:30 PM
The question was, WHY did you do it if it was for some reason other than price

Ya lost me pal.

Why did I do what???

I thought the question was metal or plastic and I thought I answered it.




I didn't know rated fan boxes came in plastic

The plastic fan boxes straddle...stradle....straddel....go around the ceiling joist and you screw thru them into the joist.

thassler
01-16-2009, 05:46 AM
http://www.terrylove.com/forums/images/smilies/smile.gif
stradĚdle (strdl)
v. stradĚdled, stradĚdling, stradĚdles
v.tr.
1.
a. To stand or sit with a leg on each side of; bestride: straddle a horse.
b. To be on both sides of; extend over or across: a car straddling the centerline.
2. To appear to favor both sides of (an issue).
3. To fire shots behind and in front of (a target) in order to determine the range.
v.intr.
1. To walk, stand, or sit with the legs wide apart, especially to sit astride.
2. To spread out in a disorderly way; sprawl.
3. To appear to favor both sides of an issue.
n.
1. The act or posture of sitting astride.
2. An equivocal or a noncommittal position.
3. The option to buy or sell a specific asset, such as a block of stock, at a predetermined price before a certain date.
Idiom:
straddle the fence Informal
To be undecided or uncommitted.

Ian Gills
01-17-2009, 06:05 AM
I only use metal boxes because I am a craftsman. And I do not feel comfortable using plastic wall boxes with armored cable.

Make sure all your boxes are accessible. We don''t want to see these things behind drywall without an access panel.

One of the benefits of a suspended ceiling in a basement...

Chris75
01-17-2009, 06:12 AM
I only use metal boxes because I am a craftsman. ...

Whatever....

Chris75
01-17-2009, 06:17 AM
I didn't know rated fan boxes came in plastic.

Huh. Learn something new every day.

http://www.aifittings.com/new_images/FB417S-entire.jpg

frenchie
01-17-2009, 06:58 AM
I only use metal boxes because I am a craftsman. And I do not feel comfortable using plastic wall boxes with armored cable.

I'm pretty sure you can't use plastic boxes with armored cable.

rgsgww
01-17-2009, 04:14 PM
I use alot of metal...and plastic.

It depends.

Chris75
01-17-2009, 04:18 PM
I'm pretty sure you can't use plastic boxes with armored cable.

If you use a bonding bushing your good to go.

frenchie
01-17-2009, 10:30 PM
They make plastic boxes with normal round k/o's? I only ever seen them with those rectangular tabs.

...learning all kinds of stuff on his thread.




What's a bonding bushing look like?