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Posted By: Admin Question on Flagpole Risers - 01/27/05 11:39 PM
(submitted via Joe Tedesco)
Quote
Joe, I have an electrical contractor that is using channel for bracing flag poled service risers.  He is cutting the channel on both sides so he can get a bend to meet his needs.  I'm not comfortable with the cutting and bending as I think the strength of the channel is in the design with the sides intact.  Can you run this through for comment by the contractor's network and/or give me any code reference that may apply to this type of installation?

- codeenforcementguy
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Posted By: DougW Re: Question on Flagpole Risers - 01/27/05 11:46 PM
That's unbelievable.

The whole idea of the channel is with the three sides intact.

Notching and bending like that will significantly reduce the strength of the strut.

If he wants to do that, use the angle adapters that the various strut mfgs all make... at least they're strength rated.
Posted By: Bjarney Re: Question on Flagpole Risers - 01/28/05 12:55 AM
 
The minerallacs are equally sleazy.
Posted By: Northbayec Re: Question on Flagpole Risers - 01/28/05 01:34 AM
That looks lovely [Linked Image] Inspectors in my area will fail installations if they are not done in a workmanlike manner (NEC 110.12). Is that a permanent installation?
Posted By: renosteinke Re: Question on Flagpole Risers - 01/28/05 01:50 AM
I've installed a number of "mast kits," and I am not really impressed with the design of the factory made solution.
I don't think the NEC discusses this issue, so i took a look at our local utility's specs:

"Periscope structures projecting over 30" above the roof must be braced....Bracing, when required, shall consist of two galvanised steel members installed at approximately 90 degree spread. Minimum size brace shall be 1 1/4 x 1 1/4 x 1/8" galvanised steel angle. Periscope bracing shall be anchored through the sub-roof with minimum 3/8" galvanised carraige bolts."
The accompanying artwork also specifies the bracing to be attached 10" below the weatherhead.

Ironically, the "mast kits" that I've been using rely upon 3/4 RMC for bracing members, and anchor to the roof with lag bolts (that might be 3/8").

Off the cuff, I would guess that this man's solution is as strong as the commercially prepared kit. It is certainly securely anchored to the mast with those multiple mineralacs. It is also quite a bit more expensive than the commercial arrangement I've been using.
Posted By: Roger Re: Question on Flagpole Risers - 01/28/05 01:55 AM
Amazing, Kendorf, B-line, Super Strut, and the others, all make just about any configuration or ajustable angle fitting that would do this job correctly. [Linked Image]

Roger

[This message has been edited by Roger (edited 01-27-2005).]
Posted By: e57 Re: Question on Flagpole Risers - 01/28/05 07:24 AM
Creates a "Metal Fatique" point on the strut, a few years in a gental breeze and its gone.
Posted By: electure Re: Question on Flagpole Risers - 01/28/05 12:02 PM
Anybody that's cut strut with a hacksaw has probably bent the last bit back and forth a few times to break it. This guy's just letting nature do the bending.

Think about it, though. The PoCo uses a piece of small diameter cable to brace their pole, and deems that sufficient.

So, what does it really take?
Posted By: PCBelarge Re: Question on Flagpole Risers - 01/29/05 12:07 AM
I have seen worse, at least he made the effort to support the mast. Not that I would pass this though [Linked Image], as Roger has mentioned, the proper fittings are readily available.

Pierre
Posted By: walrus Re: Question on Flagpole Risers - 01/29/05 12:26 PM
why wouldn't you just fold the sides of the channel(strut) in some and then just bend it?? Although less than perfect and easily could have been better and stronger I doubt that would ever break
Posted By: Trumpy Re: Question on Flagpole Risers - 01/29/05 05:47 PM
Personally guys,
I'm not sure about you, but I reckon this set-up just looks plain rough. [Linked Image]
Just as an aside, what actually takes the wieght of that cable drop, after the struts break, ie:what's on the end of that pipe?.
Posted By: nesparky Re: Question on Flagpole Risers - 01/29/05 07:27 PM
Probably the meter socket
Posted By: DougW Re: Question on Flagpole Risers - 01/30/05 11:34 PM
Not arguing against the use of struts - just the lack of proper fitting. B-Line makes a bunch of fitting that are pre-fab, or can adjust to virtually any angle.

Check here for some samples.

Strut to angle fitting to minerallac? OK.

Strut 'field expedient engineered" by cutting? not a chance.

Call it the equivalent of the Code's "as designed" language.


[This message has been edited by DougW (edited 01-30-2005).]
Posted By: Admin Re: Question on Flagpole Risers - 01/31/05 02:19 AM
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Here is a pair of pictures of typical American overhead service. The top pic is the "older" style, which, among other things, had the service conductors hahging at just the right heigth for a volley-ball net.

The second pic is the mast that replaced it. Please note that, in addition to the support braces on the roof, there is additional support where the mast passes through the eave, and an attachment to the wall as well.

- renosteinke
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Posted By: electure Re: Question on Flagpole Risers - 02/01/05 12:51 AM
John....err, I mean reno.
What type of material was used for the bracing in your picture?

I've seen plenty of these made from angle iron. The strut (anybody notice it's the oval holed type available at Home Depot?) is not only ugly, but I think it's overkill.
Posted By: renosteinke Re: Question on Flagpole Risers - 02/01/05 01:24 AM
In my mast support, I used a "mast kit", available from the electrical supply house. This kit consisted of a piece on metal bent to fit around the 2" RMC, and four pieces that were designed to accept 3/4 RMC at one end, and be anchored at the other. The single bolt that went through the strap around the mast also served as a pivoting anchor/attachment point for two of the other pieces. The other ends were bolted to the roof, using supplied lag bolts (probably 5/16"). The 3/4 RMC was purchased separate from the "kit."
Posted By: NORCAL Re: Question on Flagpole Risers - 02/01/05 02:17 AM
Is that an aluminum folding ladder in the fourth picture? That strut brace in the first picture is sloppy "workmanship" at best.
Posted By: renosteinke Re: Question on Flagpole Risers - 02/02/05 01:44 AM
No, that's not an aluminum ladder.

What it is is a 16 ft Louisville 300 Lb class 4-way Fiberglass folding ladder. Originally orange in color, it has been painted a grey-blue. The hardware on the ladder (pivots, braces, steps) are aluminum, but the rails are fiberglass.
Posted By: CharlieE Re: Question on Flagpole Risers - 02/06/05 02:19 PM
Wooden ladders are prohibited from being painted. Are fiberglass ladders permitted to be painted? [Linked Image]

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Charlie Eldridge, Indianapolis, Utility Power Guy
Posted By: renosteinke Re: Question on Flagpole Risers - 02/07/05 04:42 AM
I see absolutely nothing in the appropriate UL standards to preclude painting any ladder.
The instructions DO caution that certain solvents, etc, may damage the ladder.
Yirtually all fiberglass tools, including ladders, have an outer layer of pvc, or other plastic, to "seal in" the ends of fiberglass strands- so any outer surface coating is unlikely to even reach the load-bearing parts of the material.

More to the point, painting of ladders and other equipment is a common method of identifying them. I am sure that we can all agree that making things harder for theives is a good thing. In that respect, "ugly" is beautiful.
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