Fixing aerial

[Martin Pentreath]

Hi all,

Ever the cheapskate, while next door has ground-to-roof scaffolding up I'm going to ask nicely if they mind me popping up onto the roof to sort out my TV aerial which is on our shared chimney. From what I can see from ground level, our existing aerial is a rusty thing which long predates our tenure of the house. It works (mostly), but it would definitely be a good idea to replace it with something a bit newer while there's scaffolding up before it stops working.

I'm just mulling over how best to fix a new aerial to the chimney. It's a very wide chimney. It looks to be about five feet by two feet in cross section. This sort of lashing arrangement is the official way to do it

it's not clear whether that's supplied with enough cable for my chimney, and anyway, it would be a pretty awkward one-man job to do, and I don't think I can persuade anyone else to join me on the rooftops. So I'm thinking of using this sort of thing instead, which I would just bolt straight to the chimney, probably using multi montis that be wrong? I can't see why, but I guess they make the chimney lashing kit for a reason.

Cheers!

Martin

[The Natural Philosopher]

but it's not clear whether that's supplied with enough cable for my

Would that be wrong? I can't see why, but I guess they make the

Tony Sayer will be along in a minute to tell you exactly what is right.

But my wet finger experience says I have seen a lot of cronky s**te hanging sideways, and you need bloody good secure mounts to take wind load. So two of whatever you decide spaced far apart and a long pole, is where its at.

[Andy Burns]

When I re-did my aerials a few years back, I used this ratchet strap system, it was easy as a one-man job, and the new mast while carrying three aerials was sturdier than the original lashed wire mast carrying one.

[Nick Leverton]

OP of what not to do on this site :)

[Tim Watts]

but it's not clear whether that's supplied with enough cable for my

Would that be wrong? I can't see why, but I guess they make the

If you bolt on, you will need super strong anchors - and, worse, you throw all the load (a lot in wind - and worse still, it's a dynamic load as the mast wobbles in the wind) onto on eor two bricks which are at risk of dislodging.

If the cable is not long enough, I feel fairly sure it could be spliced longer with camble clamps.

[Harry Bloomfield]

> but it's not clear whether that's supplied with enough cable for my

> Would that be wrong? I can't see why, but I guess they make the

A lashing kit is the way to do it. The lashing kit will help reinforce the chimney, whereas drilling and fixing will certainly weaken it. Renew the coax too, but I prefer to run my coax to just inside the loft space to a socket, then have a separate feed down from there - just makes it a bit easier to swap antennas. If you can, run the coax down via an inside route rather than draped down an outside wall - it will last much longer.

[Skipweasel]

but it's not clear whether that's supplied with enough cable

Well - buy two. It's not like they're expensive.

As for fitting being a two-man job - not if you use enough gaffer tape to hold it still while you get it done up!

Personally I wouldn't use multimonties, I'd always worry that the slight fretting from the wind might make it gradually wear away at the holes. The compression of plastic plugs would seem more secure on a vibrting tugging aerial bracket.

[John Rumm]

but it's not clear whether that's supplied with enough cable for my

Would that be wrong? I can't see why, but I guess they make the

Lashing with a cable is preferable since it spreads the load over the whole chimney, rather than just a couple of bricks.

Go for a decent galvanised bracket like:

than the nasty pressed steel things. If the cable is not long enough, just order an additional lashing kit:

loop them together.

If working alone on a large chimney, I normally take a couple of cable rods with a magnet on the end up with me. That way you can lob the cable round the chimney and onto the roof, and then retrieve the end with the rods. Fold the clips on the corner brackets round the cable to keep them in place - tighten up a bit and then slide them into place with the rods.

[geoff]

In message , Martin Pentreath writes

You could always ask them

IF you're going to do a proper job, I would get two kits spaced as far apart as possible, to give the mast more stability in windy conditions

[Michael Chare]

>>> but it's not clear whether that's supplied with enough cable for my

>>> Would that be wrong? I can't see why, but I guess they make the

>> and loop them together.

I used something much more like those. However presumably it depends on the size of the aerial and pole. My aerial is a Blake DMX10A and it is on a 8 foot Larger diameter pole. As I live in an area where the digital TV signal is weak I had to use a large aerial and mount it high up. Choosing the right aerial was the biggest challenge!

[John Rumm]

>>>>>

>>>>>

>>>

Yup you can get away with flimsy on small aerials, however its still worth going for a decent quality galvanised one.

The main problem with the pressed steel ones is that they flex in one axis - so it adds a bit more wind wobble to the pole.

[Robin]

Or if (like me) you don't fancy your skills with 6-foot fishing rods on a pitched roof you could contemplate using a stack strap:

've only used it once but they have been around a few years now and there's loads of folks with more experience (here or in uk.tech.digital-tv).

[Robin]

Apologies for duplicating the inf. Nick Leverton posted last night. For some reason known only to Highwinds his and a gaggle of other posts arrived only after I replied to John Rumm's later post. Heh ho, perhaps it's time I started using Astraweb as my primary rather than backup server.

[PeterC]

and a lot of good stuff on here:

see:

[John Rumm]

Nice idea since you don't need to tit about with the corner protectors.

However do you not have the same problem of how you get it round a wide stack when you only have access from one side - there must still be a free end to retrieve?

[tony sayer]

Umm.. Well that lashing kit is only for very small installations just a small Yagi TV aerial and nothing else, and a short stub mast pole. Usually the wire supplied will fit most stacks.

If you need a longer pole there are bigger lash kits around and there is what is known an as double lash kit which will take a much bigger load still.

Only drill into the chimney brickwork if all else fails other wise the brickwork will fail too!, unless it is a big chimney of the 6 or more pot type.

Make sure the lashing wire is done up tight and the corner plates are in position. It is a very good way of doing the job I sometimes think more old stacks are held together with them than otherwise;!.

The strap type is OK bit more awkward to fix up but the most important thing is ONLY DO THIS WORK if you feel confident working at that height and you have a means of access to get around the far side of the stack.

Make sure to use a new cable preferably of the Satellite grade type its not that expensive and done will it will last for years. Also try to avoid the cheap contract type aerial sold by the sheds. You can get decent makes like Triax, Antiference and Blakes online. Its worth spending a few bob on it will server you well for years done right..

As with anything the wire will fail or loosen over time thats what usually causes this sort of thing plus very poor workmanship . Bill Wrights website will show you what can and does go wrong;!..

[Robin]

I managed it using a lassoo technique - ie make a very big loop then throw it over the stack. But I'm sure it helped that it was calm and dry and the pots weren't tall. I can't see it working if the wind's against you or you are faced with tall pots. (It'd be like those hoopla stalls at the fairs.) I'll pass on that in the hope Tony Sayer, Bill Wright et al. will answer. But possibly using a rod to retrieve one end is still easier than positioning the cable and corner pieces?

[tony sayer]

In article , Robin scribeth thus

Well thats how it can be done the lasso method, you then tie the wire up temp like then make your way around to the other sides to fix up the corner plates then tighten the bracket properly .. hence the warning don't do this unless your quite confident that you have access etc..

You still need to see where you are as the plates have to be on the brick with the wire, and the strap if used has to be on the brick too.

It may not be that high, but the wallop when you hit the ground can put you out of action for quite some time .. or longer;!....

[John Rumm]

Yup, that's ok when there are no other aerials and masts on the stack that get in the way.

[Terry Casey]

Looking at a great many chimneys round here, I would beg to differ ...