: OTA Mounts, Towers, Rigging Hardware
2011-04-19, 02:24 PM
If that's the case, then yes you can redrill the holes a bit larger with a hammer-drill and then pound in some inserts to take larger bolts.
Why a hammer drill? Wouldn't that only be necessary if his eave was masonry? Most likely it is wooden. My concern is the eave is rotten and needs to be replaced.
2011-04-19, 02:33 PM
HWP, stampeder's ideas sound good. Another option to consider is a free standing tower further from the house where you can bury it into the ground. The advantage of that is you don't need to worry about the basement roof cracking due to the weight of the tower. The disadvantage is you need to find a way to string the coax from the tower to the house (overhead might be easiest). You would also likely need separate grounding rods for the tower and the coax.
2011-04-19, 02:58 PM
Why a hammer drill? Wouldn't that only be necessary if his eave was masonry?Yep that's what I was thinking - masonry, brick, or concrete. If it is wood then yes a hammer drill is not needed, and an inspection of whether the wood is strong enough or needs replacing is a must. :)
2011-04-19, 03:35 PM
Hi there, sorry to butt in but I'm also considering perhaps a free standing tower or telescopic mast in the same neighbourhood as HWP. My house is a bungalow so I don't have the option of anchoring to the second story etc. So I'm left with putting the mast/tower in my backyard garden about 20 feet away from the house.
My idea for anchoring the telescopic mast without guide wires would be to dig down about 4-5 feet and get one of those deck footing tubes and fill it with cement to the surface. In the center put a 10 foot piece of metal (about 2" diameter) so that 6 feet or so is left sticking out of the support and then get the 30 foot telescopic mast to slide over the 6 foot piece of metal (drill through both to make sure no spin occurs).
What are your thoughts on this? Dangerous? Stupid?
The other thought was to use the same type footing support but instead put a free standing tower bolted down.
I haven't really found any info how to anchor those towers searching around so any experience people have would be helpful.
2011-04-19, 03:40 PM
boomcha, telescopic masts require guy wires, so having a base like the one you are describing would not be necessary. With a telescopic mast each section has a collar ring at the top on which you attach the guy wires, which you string to solid anchor points (steel rods in concrete, usually) with turnbuckles for adjusting the tightness. The actual base of the telescopic mast is usually a baseplate on concrete or a single anchor into the ground. The farther apart you can put the guy wire anchor points (thus the closer to an ideal maximum angle of about 60° the wires can be) the better. A guy wire angle of less than 30° is really not very stable but better than nothing.
Use the Search This Thread tool to the upper right beside Thread Tools and put in "monopole" for some more ideas along what you're proposing.
As for free standing towers, you can find lots of info about them in this thread, particularly the Delhi DMX line. The rule of thumb for those is to fill your base with 4' x 4' x 4' of concrete.
2011-04-19, 03:42 PM
HWP, why a tower? I thought you had great reception with your current setup?!
I have just created a photo album in my profile called, "Possible TV Tower Location." It shows the old footprint of the old baseplate. It shows the roof and the wall. The evestrough is made of aluminium. Do I want to make sure my tower and the eves avoid making direct contact? Do I secure the tower to my 2nd floor wall to a 2x4 wall stud through the insulbrick under the soffit? It also shows my other option -- my chimney...but I don't think it's a great idea.
2011-04-19, 03:48 PM
I don't think I would want to use the guy wires per aesthetic reasons (aka the wife). ;)
2011-04-19, 03:51 PM
When you're reading the monopole posts you should also check out Post #704 (http://www.digitalhome.ca/forum/showpost.php?p=900133&postcount=704). :)
Why a tower?
I want to be set-up for possible reception of WNGS and CKVR.
If I want to put up a Winegard HD7697P then I might as well put up a rotor while I'm at it.
I'm worried if I put all that on my chimney, then a mighty wind might blow it all off, destroy my OTA equipment, and damage the chimney to boot.
If I attach it to the chimney, then I'm going to need a long mast because my roof and my neighbour's roof may be in the way.
DXing would be fun.
My ladder is really too short for me to climb the roof safely. So I might need a new ladder for $250. That could pay for much of the TV tower. Long-term, I don't want to keep that satellite mount in my roof at the peak. If/When I sell the house, I doubt a home inspector would like to see it there. I would take my tower with me if I moved.
So far, I haven't climbed onto my roof. I gave up half way last fall and decided to call an installer to put on my pre-amp. He said wait until spring. I don't want to keep paying people every time I want to make an adjustment to my antenna. As of now, I have to climb on to my kitchen, pull up the ladder, and then climb up again onto my roof. The kitchen roof has a pretty steep pitch and the ladder does not have a secure hold of the shingles. It was clearly risky. If I have a properly installed new tower and safety equipment, then I can fiddle away at my hobby in relative safety.
I've got to price this all out. My sense is that cost wise, this is not significantly more expensive than doing the chimney installation --especially since I'd probably end up having to hire help. If the cost is reasonable, I would do this.
2011-04-19, 03:56 PM
If that's the original chimney from 1931 you are wise not to use it as a structural brace. ;)
My thoughts exactly! Especially if I need a ten foot mast to reach over the roof. Some parging has been done, but it's all original. I just added a pic of my chimney into the same album.
2011-04-19, 04:38 PM
After reading post 68 in this thread:
"Be sure you use long wood lag bolts and that you bolt right into the roofing joist not just the plywood. Use a hammer and tap on the roof... you can tell from how firm it is when you're on top of the rafter joist. Drill a small pilot hole 2 inches deep and stick a coat hanger wire down in it just to make sure your in the joist. If not seal the hole with roof tar and move over to a harder sounding spot and drill again."
I don't want to play that game and have many mistakes on the roof. My question is whom is better to find the truss and install my j mount on my roof, a roofer or OTA Installer?
I tried with a normal stud finder (depth 1.5 in. deep scan) but didn't get consistency to warrant start a pilot hole.
If this was already posted I didn't see it in the search field, please just point out the thread post number.
I doubt roofers ever worry about hammering into a stud or truss. They just hammer into the plywood.
2011-04-19, 09:43 PM
So i have a 5 foot tripod that i want to setup this easter weekend if weather permits. i dont think that all 3 foot pads will be hitting a stud is that ok ?
Should i be trying to get all 3 foot pads on studs ? 2 legs will be on 1 side of the roof and the single leg will probably be right in the middle of 2 studs on the other side.
my 2nd question is there are 3 holes per pad should all 3 have lag bolts ?
Thanks so much
ps i bought a eaves mount but im affraid that the eaves on my house wont be strong enough
2011-04-20, 01:00 AM
Most roof truss/studs are spaced 24" these days. The 5 ft Tripod opens up so the legs are 48" apart, that puts the 3rd leg on the other side of the peak on the middle stud.
Tapping with hammer usually finds the studs. If you accidentaly miss one, put a screw with sealant in the extra hole.
I like small lags on the outside holes and a big one in the middle.
The 3 ft triopd lines up with stud spacing @ 16, which is rare.
OR, You can go in the attic and add your own studs. Thats fun. :)
2011-04-20, 01:08 PM
I agree with Tom.F.1 and it is best for all three legs to be lagged into a truss/rafter. If you can't get all three legs into trusses then install a piece of 2x4 between the trusses inside the attic that you can bolt into. Make sure it is firmly attached to the trusses on either side.
2011-04-20, 06:23 PM
Thanks Roger and Tom for the help. Im still in limbo between the eaves mount and the tripod
does ABS piping become weak wile exposed to the sun ? i have a 3 foot abs pipe that could go on the rotor, i need 18 inches reserved for the hd stacker antenna. its hard to bend a 3 foot abs pipe.
2011-04-20, 06:49 PM
Tripod is good but do think about shingle replacement in the future. I never like to put holes on the roof...
Not sure what kind of house you have (bricks or wood with aluminum siding), how about side mount option?
2011-04-20, 10:02 PM
kooguy your right, between the eaves mount and the tripod im not going to loose allot of height and with the eaves mount its less of a eye soar and i dont have to worry about leaks in the future.