I don't understand how some people sleep.

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iwire

iwire

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I was surveying site lighting at a store, in the picture below please not the 400 watt fixture above the dumpster.

FallingLight_zpse13db53b.jpg


It looked OK from a distance but ...

FallingLight1_zpsceff249a.jpg


When I actually get up to it ...

FallingLight7_zpsd6cbc5e6.jpg


FallingLight8_zps55cf1a8f.jpg


So someone used a pair of 3/16" toggle bolts, installed wrong, to support a 400 watt light on an 8' lever of 2".

The only thing holding it when I got there was the bottom strut and the fact it was a malleable steel LB threaded onto 1/2" RMC through the wall and into a 1/2" x 2" reducer in the coupling.

FallingLight11_zps022eccc5.jpg


I took the head off, it was an older heavy duty fixture with a 1" thick Lexon vandal guard on it. I have no doubt it was all of 75 pounds or more. (My foot for scale.)

FallingLight17_zps2ead8766.jpg


Here is my repair, yeah the struts are long but I needed lots of options, these red bricks have hollow spots in them that will not take a drop in anchor. Ended up with four and five 3/8" anchors in each strut plus a 1 hole strap lagged into the wood under the copper flashing. I did go back and fill the old holes with brown caulk.

FallingLight39_zps6965b718.jpg


Job done, fixture working and I can sleep well knowing it is not going to fall and crush someones skull.

FallingLight41_zps2d4e96ca.jpg
 
That's a tough one. Drop in anchors scare me in brick because if the brick cracks the anchor looses all it's holding power. Something like that I might try to get a threaded rod thru the wall if I had access on the inside.
 
HackElectric said:
That's a tough one. Drop in anchors scare me in brick because if the brick cracks the anchor looses all it's holding power. Something like that I might try to get a threaded rod thru the wall if I had access on the inside.
Click to expand...

You seem strangely familiar.:p

I brought rod with the hope of doing exactly that, unfortunately I could not.

I feel the same way as you about the brick, when setting the steel anchors I worry about breaking the bricks. I don't set them as hard as I do on a cement wall. It's also why I went with so many across different bricks.

The one hole strap is going to hold things from pulling out, the anchors should really only be dealing with sheer forces.
 
I have talked with guys who have used epoxy anchoring for that type of application. I have never used it, but they tell me that there are versions that work well, even if you drill into one of the holes in the brick. Of course the brick has to be in good enough condition that the brick itself will not pull out of the wall, and there is also the time factor before you can put load on the epoxy anchor.
 
I agree about that 2 hole strap holding it in itself.


BTW, it's nice being able to get a boom lift to work off of. Most companies would have their guy on an extension ladder or hanging over the roof :D
 
I had an issue with goosenecks pulling out of brick using lead anchors, which I am not fond of but was told to use. I tried using drop ins with epoxy (not the rated system :slaphead:) and that didn't work either.
Darn you inferior Hudson river bricks! :lol:

I then used lag expansion shields and they have held thus far...

Are there any other systems you guys have had success with in brick?
 
I would imagine that it is critical to drill the right size hole and control the expansion bolt tightening to avoid cracking the bricks. Or were they soft enough that that was not an issue?

Tapatalk!
 
So that works as long as there is open space on the far side of the brick, and the toggle bar does not cut through the brick as the load flexes and vibrates.


Tapatalk!
 
GoldDigger said:
I would imagine that it is critical to drill the right size hole and control the expansion bolt tightening to avoid cracking the bricks. Or were they soft enough that that was not an issue?
Click to expand...

With these old blocks with hollows in them it is critical that I hit a solid area and I don't work with them enough that I always know where they are solid.

Different brick companies made them differently.

https://www.google.com/search?q=red...rB2wXVrIHQBA&ved=0CAYQ_AUoAQ&biw=1024&bih=651


K8MHZ said:
Bob,

I see there is another light over the handicapped parking spot. Did you check to see how that was holding up?
Click to expand...

GoldDigger said:
Looks like the same mounting method. Maybe the brick is better over there.
Click to expand...

There are two more lights really and it seems the bricks are better over there, that end of the building is newer.

That said there were still issues I corrected.

Here is light number 2

FallingLight52_zpsb2ad6e3d.jpg


No strut clip, the pipe is not against the strut, the two strap was pulling away from building. Once I installed new straps with better lags the pipe pulled into the strut and I installed a clip on it.

FallingLight50_zpsb40d1a9e.jpg


The bottom end

FallingLight53_zpsae609442.jpg


Here is one of the screws that had been used for the two holes straps, I replaced these with 2"x 5/16" lags.

The light that was falling away used to have a two strap on it but the screw head had snapped off of these under sized screws.

FallingLight60_zpsccf93146.jpg


Light number 3

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Interesting hardware here.

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I am not big on how this looks with two straps and a bunch of washers but they are holding very strong and from the ground are really out of site.


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Lights 2 and 3 now look like this.

FallingLight69_zps2443d39f.jpg
 
Well, there's brick, and then there's BRICK. Only the installer knows what he has.

At the one extreme, you have old Chicago 'fired brick,' which is hard as a rock. In that stuff, you can get real good results with drop-ins, hammer-ins, and even Tapcons.

At the other extreme, you have the West Coast "terra cotta" brick, which is only slightly stronger than dried mud. For that, I use this fastener, which sort of resembles a cross between a drop-in and a hollow-wall "Molly bolt:"
http://www.planitdiy.com/wp-content/uploads/2011/04/Molly-Bolt.gif

This type of anchor opens up a lot more than drop-in.
 
renosteinke said:
Well, there's brick, and then there's BRICK. Only the installer knows what he has.

At the one extreme, you have old Chicago 'fired brick,' which is hard as a rock. In that stuff, you can get real good results with drop-ins, hammer-ins, and even Tapcons.

At the other extreme, you have the West Coast "terra cotta" brick, which is only slightly stronger than dried mud. For that, I use this fastener, which sort of resembles a cross between a drop-in and a hollow-wall "Molly bolt:"
http://www.planitdiy.com/wp-content/uploads/2011/04/Molly-Bolt.gif

This type of anchor opens up a lot more than drop-in.
Click to expand...

We call those 'Rawls', probably after one of the manufacturers. They were the fastener of choice for a company I worked for in the 90's.
 
I like tapcons in brick, but with a fixture of that weight I think you have to have a few options at the ready and be willing to compromise on looks a little bit. I agree on the wondering how people sleep, you can tell when a fastener has really grabbed verses kinda grabbed. Shame on people who don't care when its a heavy overhead item.
 
In the early 80's I worked with a jack leg electrician. That's a stretch calling him an electrician but that's what he was hired as. He would have installed this using plastic anchors. He was finally fired one day for shoddy work. All of his work was shoddy though.
 
The problem with the original install is that masonry is for compression forces only. If we need to resist tension we place rebar in hollow cells of block and fill the cells with grout. Brick was formerly used as the structural wall by laying multiple wythes of brick aside each other but today we use block walls with brick veneer to accomplish the same aesthetics.

Sure you could lay one brick on the ground and slap some mortar on it and put another brick on top and come by the next day and pick up the top brick and the bottom brick will come with it, but it's not going to survive in that position very long if there's thermal dynamics, water, ice, snow, etc. These light poles are subject to all that plus wind, seismic, workers changing bulbs & ballasts, etc. They're just not going to last in that condition with those latteral forces.

Mortar is good for around 700 psi. A brick is usually good for a little more but as already discussed bricks vary considerably. In comparison, portland cement concrete is good for 2,000 -2,500 psi or more.

To avoid the problem of trying to anchor into a hollow cell of a brick and causing complete failure of the brick, many people will insert their anchor into the mortar joint. Those joints are around 3/8" so if you use a 3/8" diameter anchor, or one that uses a 3/8" hole, at least you're not damaging the brick to the point where the brick is going to fall apart on you. Also, if a brick is not solid and you need greater than a 3/8" hole for your anchor, you'll be at the edge of the brick which is as far as you can be from the hollow areas of the brick.

It looks like OP did a fine job for his customer which should last a long while.

Hope this helps. That's what this site is for.
 
good job done man.......first of all thanks for repairing that..you have really saved someone's life...now about the light it look ok to me after repairing...:)
 
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