String Line - Laser??

[Mulberry View]

I need to throw a straight line between 2 points that are about 250 feet apart, ideally in the daytime.

 

I can see both points and have clear line of sight, but it'll be hard to run a string, not to mention keep it taught. Does a laser pointer exist that will do this? I don't need it to measure or level, just show me a line. Once I have that, I can get some markers down to ground level.

 

Can be cheapy Chinese Amazon type thing, or something perhaps I can hire if more expensive.

Edited July 14, 2021 by Mulberry View

[Mr Punter]

Can you drive in a stake nice and upright either end then use them as a sight line for the intermediates?

[joe90]

Being old school I prefer string/line, I have a roll of electric fence wire (platted nylon with wire ) which is very strong and does not stretch .

[markc]

Definitely sight line as Mr Punter says, you just need a 2nd person to sight or mark

[saveasteading]

Ranging rods. either by pure line of sight or using a site level.

Very easy to see, tall, have sharp points and appropriate diameter for projecting along the line.

 

They are not expensive, can be found in sectional form (for storage and to make extra high) , and are handy for any marking out....so handy for other people that they keep disappearing.

 

[Mulberry View]

  On 14/07/2021 at 12:00, saveasteading said:

Ranging rods. either by pure line of sight or using a site level.

Very easy to see, tall, have sharp points and appropriate diameter for projecting along the line.

 

They are not expensive, can be found in sectional form (for storage and to make extra high) , and are handy for any marking out....so handy for other people that they keep disappearing.

 

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I had no idea about this, but I can see how it would work.

 

The clear line of sight is at a bit of a height though (above a 2-3m Laurel hedge), so that might scupper things.

[ToughButterCup]

250 feet ... in the daytime. Thats asking a lot of a laser. But nothing to an optical instrument ...

If you are set on lasers, at that distance, I'd use the laser rangefinder I use for shooting  . That one's a bit expensive for what you want but there are many for less than £80

Edited July 14, 2021 by ToughButterCup

[SteamyTea]

How important is it that the two heights are known?

[Onoff]

Couple of hosepipes to make a water level. Pretty foolproof imho.

[saveasteading]

  On 14/07/2021 at 13:23, Mulberry View said:

(above a 2-3m Laurel hedge), so that might scupper things.

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Choose one or more of the following.

 

1. Cut the hedge locally....you will know where when you start. For first approximation you can have someone hold it high.

2. Stand on a box or step to see over the hedge.

3. Buy  rods that are in sections so can go higher.https://www.yorksurvey.co.uk/1m-point-jointed-pole-section-c2x23061987

4. Tie to a post (or in the hedge.

5. Make your own with very straight timber.

 

OR buy a laser and be disappointed that you still need rods, and can't see the laser beam.

 

Once you have done this retro method you will be in tune with the Egyptians, Romans and our own industrial revolution.

Sometimes the old ways are best....these are still for sale so plenty people still using them. They look good on your site too, and are a good way to wind up the neighbours that a road is coming through..

 

 

[Mulberry View]

  On 14/07/2021 at 14:09, ToughButterCup said:

250 feet ... in the daytime. Thats asking a lot of a laser. But nothing to an optical instrument ...

If you are set on lasers, at that distance, I'd use the laser rangefinder I use for shooting  . That one's a bit expensive for what you want but there are many for less than £80

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I'm not set on anything specific. As I said, I'm not concerned with anything other than the position and straightness of the line. I need to put a marker in, on the line about halfway along and only need the physical position on the ground, so the visual line-of-sight method will work I think, as long as I can see it over that distance.

 

In a nutshell, we are splitting the property perpendicular to the longest boundary of the whole plot. That long boundary has 'slipped' by a fairly substantial amount (over a metre along its entire 70m length), but as we are now going to fit a proper fence I'd like to get the bit on the land we are retaining as close to being on the correct line as possible. The bit on the land we're selling is for the new owners to argue if they wish.

 

I am having our land surveyor back for other stuff but I'd ideally like him to survey the fence once completed, as opposed to him coming earlier to peg out the position.

[Mulberry View]

  On 14/07/2021 at 14:16, SteamyTea said:

How important is it that the two heights are known?

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Not at all important.

[Mulberry View]

  On 14/07/2021 at 14:25, Onoff said:

Couple of hosepipes to make a water level. Pretty foolproof imho.

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Errrr, excuse me?! What is this?

[Mulberry View]

  On 14/07/2021 at 14:52, saveasteading said:

 

Choose one or more of the following.

 

1. Cut the hedge locally....you will know where when you start. For first approximation you can have someone hold it high.

2. Stand on a box or step to see over the hedge.

3. Buy  rods that are in sections so can go higher.https://www.yorksurvey.co.uk/1m-point-jointed-pole-section-c2x23061987

4. Tie to a post (or in the hedge.

5. Make your own with very straight timber.

 

OR buy a laser and be disappointed that you still need rods, and can't see the laser beam.

 

Once you have done this retro method you will be in tune with the Egyptians, Romans and our own industrial revolution.

Sometimes the old ways are best....these are still for sale so plenty people still using them. They look good on your site too, and are a good way to wind up the neighbours that a road is coming through..

 

 

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Hilarious, but useful. Thanks for your input. I think I shall use some rods fashioned from materials I have or can easily obtain. This is for a generalised guide, it'll be as accurate as I need it to be.

[Onoff]

  On 14/07/2021 at 19:40, Mulberry View said:

 

Errrr, excuse me?! What is this?

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You can use a garden hose(s) and just attach some clear sections each end with jubilee clips etc. Just make sure the air's all out.

 

 

[PeterW]

If you want it for legal purposes then get the surveyor to map it with a GPS marker and then transpose this to the floor with pegs. He will be able to do it within 30cm. 

[Marvin]

  On 14/07/2021 at 14:25, Onoff said:

Couple of hosepipes to make a water level. Pretty foolproof imho.

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250 foot hosepipe! Big garden you've got!

[Onoff]

  On 14/07/2021 at 21:14, Marvin said:

250 foot hosepipe! Big garden you've got!

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I have. 

 

[Oz07]

Some rotary levels so this and mark with the reciever. Mine does. Also gives 90 deg

[saveasteading]

Perhaps veering into a different subject but...new v old surveying.

 

Modern equipment and methods are very easy and precise. So on this post it would be feasible to get a land surveyor with a fancy machine to mark your points out for half a day's pay...£300. You should be in attendance for banging posts and any decisions.

 

But it is much more fun and satisfying to do it yourself, and in doing so you might also notice any quirks in the landscape, and change your mind where to put this new boundary.

 

Walking the land and doing the work yourself is the way of understanding the possibilities and challenges of a project.

 

 

Why do I resist modern methods? I don't, but they are so easy to use that they are used by some people who don't really understand what they are doing , and  mistakes are missed.

Expensive mistakes if not spotted.

 

Everything needs to be looked over, just by eye and perhaps pacing to check for anomalies. For example here, if the satellite guided positions of 4 posts don't look straight.

 

Laser levelling can go wrong too. The modern groundworker uses them, but doesn't know the principles of levelling. So if it is out of adjustment, and using long and short sightings, big errors can arise.

 

Best way to check if a building is a rectangle? Measure the diagonals, by pacing then with a tape.

Best way to pour trench concrete level? Not with a laser level and staff on the wet concrete imho.

 

And most importantly, know your stride length. This costs nothing.

 

As for water levels recommended above They are invaluable in confined spaces. I spent 2 uncomfortable days under a Boots pharma factory, but there was no other way with 4 ft headroom.

For the cost, everyone should have one. This one is £10, and if you fix it to timbers, as the following pic, you have control .You can get a hydraulic oil version with digital readout of level difference for £400.

 

 

 

 

 

[SteamyTea]

  On 15/07/2021 at 10:57, saveasteading said:

new v old surveying

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All goes back to here.

The Cornish Mother of all surveying.

[saveasteading]

The High Street under water again?

[JFDIY]

Piece of cake with a rotary laser level and receiver

 

[Mr Punter]

  On 15/07/2021 at 20:56, JFDIY said:

Piece of cake with a rotary laser level and receiver

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But I think the OP wants line, not level.

[Cpd]

Just buy a roll of high tensile fencing wire, attach at one end, roll out and tension at the other end and tension it….

Edited July 16, 2021 by Cpd