Are these multi-cable electrical staples goofy, or is it me?
I just tried to use one of the red Gardner Bender Multi-Cable Staples for the first time, and I’m puzzled. I had two 14-2 NM cables to secure, but the plastic slots on this product don’t grab the cable at all; it can slide up and down quite freely and side to side an inch or so. I did close it completely. I’m using plastic single-gang boxes that don’t include a clamp. My understanding was that one staples a cable snugly (without squashing it) to keep it from pulling on its connections inside the box. This product is labeled for 14-2 NM, but it seems to be designed for something thicker. I could put two 14-2 cables under one of the plastic staples with a nail on each side, but the resources I’ve read are quite mixed on whether this is okay. I don’t have room to “weave” multiple cables up the middle of a 2×4 so that each has its own staple. Am I missing something about the multi-cable staples, and how do you handle two 14-2 NM cables that have to be stapled onto a 2×4?
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> I had two 14-2 NM cables to secure, but the plastic slots on this product don’t grab the cable at all; it can slide up and down quite freely and side to side an inch or so.
Practically speaking this isn't really a big deal.
> I’m using plastic single-gang boxes that don’t include a clamp.
The boxes have an integral clamp, usually.
> I could put two 14-2 cables under one of the plastic staples with a nail on each side, but the resources I’ve read are quite mixed on whether this is okay.
The staples will say what they're rated for. Many are 100% fine holding two 14-2 or 12-2 cables.
Depending on exactly what I'm doing, I use staples (via my Dewalt stapler), those plastic stackers, or Colorado Jim metal straps (more common in metal stud/commercial framing, but I like them a lot). All have their place.
Thank you, Patrick.
Am I mistaken that the main purpose of staples is to keep the cable from pulling on its attachments inside the box?
The single-gang plastic boxes from Carlon don't have integrated clamps. The double-gang ones do.
The package says what size cables the staples can hold, but nothing about how many cables per staple.
With plastic boxes, the cable "clamps" leave a lot to be desired. Metal box cable clamps are far more secure. The cable staples aren't really there to keep the cable secured in the box, but they do keep at least some of the strain off of the box. I like to make a sharp bend in NM cable where it goes into a plastic box so that the sharp bend acts as a sort of cable stop so that the cable won't easily pull out of the box. You really don't want the individual wires in the cable exposed outside of the box -- the cable and it's outer jacket are supposed to enter the box.
There is nothing wrong with the multi-cable supports. The two nails and a plastic piece cable "staples" (which I much prefer over the metal staples) don't hold the cable tightly, either. Thing of the cable supports as devices intended to keep the cables in rough position, so that they don't get nailed by the drywall guys when they hang drywall. The cable supports aren't really there to completely stop all movement of the cable.
I wouldn't have a problem using the cable supports. You could put everything in with those and add something tighter if an inspector asks for anything extra, or just call the building department and ask ahead of time.
Bill
Thank you, Bill; "cable supports as devices intended to keep the cables in rough position" explains why those multi-cable staples don't seem to do anything more.
Technically, those multi-cable supports are supposed to "maintain spacing" too. The intent is that you don't want all the cables in a tight bundle where they will mutually heat each other up -- you need some air space around them to allow for cooling. In a typical residential electrical system, this isn't usually much of an issue as long as you don't intentially bundle cables together (tape, etc.).
Bill
Good point, Bill. I did note that they kept the cables separated, but forgot to credit them for that. I'm just surprised staples that don't reduce any direct pulling are just as acceptable as ones that do. I do see, per your previous comment, that keeping the cables roughly in position helps to prevent indirect pulling that would result from them flopping around side to side.