Mast bracket

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This is a quick bracket I built to stiffen a mast that passes through my attic. It's not structural but rather just dampen wind vibration. The u-bolt is a standard exhaust style and the triangle was cut from a piece of scrap. Attached Images
Reply:Nice, simple design. Those are the kind of fixes people say " wow, why didn't I think of that". 1 ATABOY.
Reply:Bracket looks good. How about the flashing around the roof penetration? Looks like water stains on the plates directly under the rafter. How solid is the bottom of the rafter/top plate area?
Reply:that sailboat aint goin anywhere
Reply:Looks good forhire.  How about another one tied into the underside of the wall plate for bi-directional support?Just curious - antenna, electrical service entrance or periscope?MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Originally Posted by daddyBracket looks good. How about the flashing around the roof penetration? Looks like water stains on the plates directly under the rafter. How solid is the bottom of the rafter/top plate area?
Reply:looks good
Reply:Originally Posted by duaneb55Looks good forhire.  How about another one tied into the underside of the wall plate for bi-directional support?Just curious - antenna, electrical service entrance or periscope?
Reply:First, nice simple clean design and execution.  So, But some picking on details.  You state 'not structural, just to dampen vibrations'.  Well, that actually means it IS structural, because vibrations can rip apart a structure pretty quickly.  Look up 'Galloping Gertie' about the Tacoma Narrows Bridge and how wind-induced vibrations set up the bridge into a harmonic vibration that literally ripped the bridge apart into a complete and total structural failure (the bridge collapsed).http://en.wikipedia.org/wiki/Tacoma_Narrows_bridgehttp://en.wikipedia.org/wiki/Tacoma_...s_Bridge_(1940)Vibration -IS- a structural issue.Next, 2.5 inch diameter pipe for a fiber optic cable?  Wow, that's some fiber.  Connecting the vibration issue to the 2.5 inch diameter pipe, if you have that size pipe vibrating, then you do have to check and fix why.  It could have just been an original inadequate mounting arrangement, in which case your bracket/brace may be a good fix.But depending on how much of that pipe is sticking up through the roof and how much load/vibration is going on, I could see the pipe kinking itself right at that skinny u-bolt because ALL the side forces/vibrations are pushing right there.  You -might- want to rig up some sort of saddle to spread the loads/forces across more of the pipe.If you make a similar brace to go the the next roof rafter to the 'left' of that one, remove the U-bolt and sandwich the pipe between the two braces, it would be a lot stronger and stiffer.  The current U-bolt brace -could- be enough, the 'double braces' might be overkill.    But bracing between two roof rafters also helps spread the forces between the two rafters and helps keep the pipe from flexing the one rafter sideways and messing up the framing and/or roofing.  Tying in to two brace points is usually better than just tying in to one.  All-in-all, like I said, simple clean item.It could be enough, or you might need some more bracing.  The best laid schemes ... Gang oft agley ...
Reply:Originally Posted by MoonRiseNext, 2.5 inch diameter pipe for a fiber optic cable?  Wow, that's some fiber.  Connecting the vibration issue to the 2.5 inch diameter pipe, if you have that size pipe vibrating, then you do have to check and fix why.  It could have just been an original inadequate mounting arrangement, in which case your bracket/brace may be a good fix.