Hi. I got some great feedback on the overall question of where and how to install my sensors in this thread: http://discourse.weather-watch.com/t/35430. Based on your excellent feedback, I finally figured out a good solution that deals with lots of site and house issues. But…
There’s one last issue - the anemometer mast. More specifically, the material size and type, and how to mount it so that it can be tilted down.
Requirements:
Mast Height: 12-15 feet long to get 7-10 feet of exposure above the roof ridge.
Size and Material Type: Stiff pipe that is relatively unobtrusive, would flex very little, and be relatively easy to install.
Mounting: Mast can be lowered for maintenance.
Mounting base: Mounting the mast is the most difficult. To make it accessible for safe installation and lowering I’d prefer not to mount it directly to the cedar shake roof. Below is a drawing of the location and kinda/sorta what the mounting might look like.
That particular section of the roof is almost always dry, so there is good footing. Also, the eve structure provides a solid mounting point if the mounting point is extended out past the gutter (the white box). The wood frame would rest on the roof shingles, but not penetrate them. The wood frame would be anchored to the wall.
Other than the mast location, I am open to any solution. I’d very much appreciate you feedback. What do you think of my solution? A better approach? Will this mounting be stable for the 12-15 ft mast? Is a 2 inch aluminum pipe sufficient for the 12-15 ft mast? Is it overkill? Better options?
Thanks in advance for any feedback,
Dan.
p.s., one vendor told me that he didn’t have a tripod mount that would handle the mast height I need.
It looks quite much same as mine mast-mounting, with the difference mine is mounted on a fence. I have mounted it to a wooden fence and there with a couple of big bolts. Then I have 2 guywires to prevent to much wobbling. Its a homebrew metal/wooden mast where lower 2/3 part is metal and upper 1/3 is wooden due to stormtracker. Total height of my mast is about 24 feet.
The good side with this mount is, its easy to take down for maintenance while the lowest bolt works like a hinge what then pick it on place when lift/low it. I have had it in mind from the first place to have it easy to take down when needed without having a hours work to do it.
That’s an idea. I have one mounted that way using strut channel, depends if the chimney is high enough to get a decent spacing between the mountings. If he burns a lot of wood it might not be such a great idea though…
Below are two pics of the location. It’s the back of my house next to the upper deck.
The eave (yellow line) has two measurements. The first is from the wall to the inside of the board that supports the eave - 29". The second is from the wall to the edge of the gutter - 35-1/2". All eave measurements (yellow and red lines) are the same.
The height of the eave (blue line) from the location where the mast base would be to the bottom of the gutter is approximately 42". From the mast base to the top of the inside board (to which the gutter is attached) is 48"
OK, here’s my suggestion. Two pieces of strut mount (blue), a long upper one, looks like you would need to shim it out so that it’s vertically above the lower one. You would have a really secure mounting because of the large spacing between the mounts.
There is another option, depending on the cranked stand off, i dare say you can get a lot
bigger stand off than this one but it gives you another idea to work with, i know its UK but
im sure you can get them over there too
does it have to be on the roof. How about a mast along the side of the house then you can attach your guy wires to the top of the mast for sway support. Use standoffs to mount the mast on the lower to the side of the house and finally sink the base of the mast in concrete.
This way, you won’t have to worry about the roof leaking through the shakes, or risk a good straight line wind ripping the thing off the roof.
Or… you could get one of those HAM radio towers. Fix it so that you have a concrete base and use that for the unit. I know of a guy who did that, and fixed the base that it had hinge on two sides of the triangular that would allow him to undo the fourth nut and allow the tower to be tipped down if work needed to be done. Then he mounted the Anenometer on that as well as the ISS. Put a screen in the rain bucket to keep the birds and twigs out.
As there appears to be an existing vertical surface forward of the roof pitch overhang…(see piccie below)…maybe use as long a mast as possible attached and supported by that existing surface…some additional support within the structure may be needed, but it all looks accessible and could probably take a very long pole/mast sufficent to get well above the roof line…very simple attachment blocks could be made out of wood if required and even steel TV Ae mast supports could be used.
This is what i have done with my mast Baggins, but mine is attached to the post not the actual fence
Not sure how sturdy his is but mine neeeded guy lines and looking at the height of his pitch he will
also need guys if hes to get hight then the pitch, its all down to whether he can place the guys suitably… but mine has held up well considering, i think the post is about 4x6 inch and about 5ft high
with the stand off brackets about 4ft apart…
It’s difficult to judge the actual internal construction of the vertical area indicated, but as there appears to be some sort of inner plant box, I was assuming that there may well be some 2 x 2 (or 4) within that could be utilised or beefed up for strength. It quite surprised me how long a good steel pole with an upper alluminium extension can be made to go with just base support…mine is some 15ft long with chimney brackets (it can be rotated around the lower fixing for access when needed, but I still have to get to the chimney stack…nb, that they are NOT being used)… …and mine has withstood 60 plus mph winds no prob…
I think Niko’s or Baggins’ idea comes very close. These ideas are much better than mine.
Regarding Niko’s idea. The base of the mast could attached to the top (horizontal portion) of the planter. Then build a mounting block on the board that supports the eave that’s 90 degrees to the planter (runs parallel to the back deck). That way the standoff would only need to be about 8-10".
Regarding Baggins idea, this would be dirt simple to do. It would have to go about 1 foot to the right to miss the door (there is a small “garage” below the planter). I’d have to add an additinoal 2X4 behind the wall and 4’ piece of cedar 1X4 to the outside face to miss the planter lip. That’s about it.
One thing regarding guy wires - I don’t have any place to anchor them except to penetrate the roof. To counter that, I want to use stiff aluminum pipe for a mast. I hope 2" in diameter will be enough.
Upsides of Niko’s approach:
Would place the top mounting bracket something like 4 ft higher. This means that the unsupported mast would be something like 14 ft or so.
About a foot or so closer to the roof ridge and away from the trees in the back yard.
Upsides of Baggins approach:
VERY simple install.
Easy and safe to mount and dismount the mast for maintenance.
Somewhat nicer appearance - No braces or mounting hardware above the planter.
Since I want a mount with no guy wires, one concern I have about both of these approaches (and my original one) is having a stable mount for the Anemometer. The unsupported mast will be something like 12-15 feet. Will a 2" aluminum pole be stiff enough?
It may be possible for you to get, say a 12ft steel pole of say OD 2 -2.5" and then insert an aluminium extension (1.5-2 " OD) of about another 8 to 10 ft, into the steel mast with a pair of bolts through and some gaffer tape to take up any slack…This is how I did mine…My lower support brackets are quite close, but sufficently far apart to give rigidy…If the mast is not quite vertical when it is put up into the supports it is quite possibe to use wedges within TV Ae brackets to correct the problem…again, I had to do this myself, to get the mast visually/truly vertical …It may be difficult for you to get straight aluminium of 15 ft length in 2", but over here I discovered that the local Ae erectors seemed to top out about 10ft using aluminium…the extra length of 5 ft with just base support would possibly show some signs of whip higher up…but it does depend on the wall thickness/quality of the aluminium anyway
Thats one thing i dont really recommend is bolts through the mast…
Back in the good old CB days i had a 21ft scaffold pole with a 15 ft aluminium.
The aluminium was joined inside the 21ft using that method, it was also guyed.
There was some good strong winds one october and the mast bent right at the
bolt hole and brought the 15ft down, the 21 ft was attached to the house using
3 stand-offs, about 6ft apart, i dare say it was too high to begin with and perhaps
it wasnt guyed to spec but it was pretty secure, or so i thought, i was gutted,
setup reached all over the world…
I can see your point bashy, but in my case the bolt holes are basically very small diameter with respect to the pole diam and are there to just support the added pole in a vertical sense only…in fact the fit of the aluminium into the steel was very tight indeed and it was really just an afterthought to drill a small diam hole right through with a fixing bolt (x2) to give that extra security…I am very familiar with fatigue fractures and the presence of, in ac and the like with adjacent structures…however, I suspect that I’m more likely to have failure with bimetallic corrosion than anything else!!..Alternatively, it may be possible to join the 2 poles together with a sleeve clamp, but that is likely to add weight and additional moment at a bad place and look somewhat unsightly…
Edit: I suspect that in reality for the length/height of the mast that you require and NOT using guy wires that you will need to investigate the use of a steel scaffold pole (much like Bashy has suggested) if you can get one long enough!!
Need a creative solution :?
…and mine has withstood 60 plus mph winds no prob…