Hangers into metal

[568B]

The current job has wood trusses, with metal U channels screwed to the bottom of the wood trusses at a 45 degree angle for the entire ceiling. So once the drywall is installed, we will only be able to reference the screw line where they attached to the metal U channel. We have no way to screw into wood.

Question - How to attach 300 hangers securely to thin metal U channel (similar to metal stud thickness). Maybe drywall or self tapping screws do work but just concerned about pulling out. We will have 70 cat5e cables at the heaviest point. Any advice on how you secured hangers to (basically) metal studs would be helpful.

 

[franklin97355]

At your heaviest point you need to spread your load among several hangers.

The answer is "42"

 

[Crowtalks]

If they have a lip on them, you can still use 1/4 inch beam clamps.

NCSS NCTS NCTE

 

[568B]

This is a drywall ceiling attached to metal studs. I need to go through the drywall to the metal stud.

 

[mikeydidit]

Just use a self tapping screw heavy enough that you don't worry about them pulling out. They would only need to be around 1 1/4" long. I would try to use the hex heads. They seem drive in better without stripping out the heads. Suck them up good against your j-hook without stripping them out of the metal. Place them close enough the disperse the weight.

The wireless telegraph is not difficult to understand. The ordinary telegraph is like a very long cat. You pull the tail in New York, and it meows in Los Angeles. The wireless is the same, only without the cat.

Albert Einstein


For the best response to a question, read faq690-6594

 

[oldtimerbob]

It all depends upon the thickness and the type of metal of the metal studs you are having to attach to and the amount of cables going to each.
For thinner metal:
I would use a hilti solution and shoot the wire to the studs.
For thicker metal:
The use of the self-tapping screws with a small ell bracket to attach the wire to for cable runs of 30 of less cables should work.
For runs with more cables, you will want to use all thread(then you can put multiple j-hooks on)and break up the large runs into a couple of smaller ones.

You may want to check with your electrical contractor on the job and see what they are using,or ask for suggestions from them also.
Good Luck,


Has been in the cabling business for about twenty years and is now the Sr PM for a cabling company located in the Los Angeles area.

http://www.globusinc.net

Also a General Class Amatuer Radio Operator.

 

[CablingContractor]

This sounds like what we call Hat Channel. I use a large self tapping screw. It you need additional strength, use a hole saw and a toggle bolt.

 

[1043]

Toggle bolts

 

[568B]

Thanks to all who replied. Again, we only have the light guage metal stud to attach to...NO WOOD.

I went to 3 of our local faster supply houses and got samples of all types of screws. I tested about 10 different screws/sizes into a spare piece of the u channel: self tapping, sharp point, #8, #10, #12, fine thread, drywall. I was VERY careful not to over tighten and strip the metal.

Of all tested I found the sharp point fine thread to have the best for holding strength. The sharp point left an oval type hole which gave it much more to grab. I could not pull these out.

The self tapping screws left a perfectly round hole with not much bite...I was able to pull these right out with minimal effort.

 

[dhnl]

Probalby overkill but we use a lot of these for all sorts of things:

http://www.toggler.com/products_hwh_installation.html

 

[mikeydidit]

Not sure ho hard they are to get to, but you could always drill them out 1/4" and just put in a 1/4" bolt and nut. Those are cheap and will not pull out. It only takes a minute drill out the j-hook to fit also.

The wireless telegraph is not difficult to understand. The ordinary telegraph is like a very long cat. You pull the tail in New York, and it meows in Los Angeles. The wireless is the same, only without the cat.

Albert Einstein


For the best response to a question, read faq690-6594

 

[LkEErie]

Erico has a new brand of Caddy Fastener (for Cat-6 and 7 specs) that have both the angle brackets, beam clamps and hammer-on fasteners as seperate pieces that snap on the basic J-hook. You now get parts like 16/32/48/64 for 1/2/3 and 4 inch hooks.

http://www.erico.com/public/library/Fixing/LT1434.pdf

gets you to the page of parts.

LkEErie

 

[dgyde]

The sheetmetal screws may pull out. For holding serious weight, check out the "Snap Toggle" from

http://www.toggler.com.

You can get them a Fastenal, or many other distributors.

We use snaptoggles to install LCD and Plasma TVs based on manufacturer's safety requirements in commercial situations where there are metal studs and no extra blocking. These are amazingly strong, and you can use 1/4-20 threaded bridle rings (4 in) to support your cabling. You'll drill a 1/2 in hole through the center of the metal stud (above the drywall) (make sure you hit close to center), and then insert the snaptoggle. Then you'll screw the bridle ring in through the hole. It should work like a champ.

- Dave

http://www.theinsidewire.net