2" wide slit trench

[Bazza]

I've just laid underground drainage using 80mm permeable pipe in trenches t hat were 6 inches wide and up to 24 inches deep. What I want to do now is t o create some very narrow slit trenches that can channel water towards the

80mm pipes.

So I'm looking for tips on how to create a trench 2 inches wide and 18 inch es deep. This I would line with permeable membrane and back fill with sharp sand and small shingle.

I've looked for a spade with a totally flat blade and a handle that is in l ine with the blade ie something like a lawn edger with a deep blade. So far no luck. I reckon once the side are cut it should be possible to hoik the soil out with some sort of "L" shaped metal tool.

Any suggestions would be welcome.

[michael adams]

....

If this is in soil and there are no obstruction then why not just dig out a wider 18 inch trench, with one straight side. Then working in sections wrap your permeable membrane around a length of 2in wide/thick 18in deep timber/ply , back filling both sides as you go. First soil outside then pull out the timber, and sand and shingle inside. You'd probably need to work in short sections 4-6 footish ? to prevent the trench collapsing.in any case.

michael adams

...

[michael adams]

I fact thinking about it, this could be a continuous operation. Rather then pulling out the timber former, it could be slid along, the backfilling of both sides proceeding on a foot by foot basis. The former would not need to be solid timber ply each side with odd bits of timber around the edges and maybe inside. But smoothed off so as to slide easily

If the entire trench was dug out first, one straight side one sloping then the membrane could be laid out in the trench with no folds etc. This would be problematic in a narrow trench, given the possibility of collapse.

michael adams

...

[harry]

that were 6 inches wide and up to 24 inches deep. What I want to do now is to create some very narrow slit trenches that can channel water towards th e 80mm pipes.

ches deep. This I would line with permeable membrane and back fill with sha rp sand and small shingle.

line with the blade ie something like a lawn edger with a deep blade. So f ar no luck. I reckon once the side are cut it should be possible to hoik th e soil out with some sort of "L" shaped metal tool.

Google drainage spade.

[michael adams]

- Google drainage spade.

Why not first try Googling "2 inches wide" ?

michael adams

...

[Bazza]

The soil is free of obstructions like stones. Ithas a high clay content so there is litle chance of collapse as it would take the sides several days to dry out and become unstable.

I've been thinking of getting an all-metal spade and heating up the blade red hot then flattening it. Then straightening the shaft so that it is in line with the blade. Is this feasable?

[Roger Mills]

The utility companies appear to be able to cut very narrow trenches for cable laying. What do they use to make the cuts?

[Bob Minchin]

You can get a trenching machine. Sort of a cross between a chainsaw and a dredger on a mini digger.

[nospam]

I've been looking at hiring one of those because I may need to replace the pipe from the main to the house - there are some impressive demos on t'web.

Watch out for cables and gas pipes!

[The Natural Philosopher]

sort of rotary excavator IIRC

[Andrew Mawson]

Google 'mole plough' and make one suitable for your circumstances

Andrew

[John Rumm]

I would expect the only way to get a 2" wide trench would be to hire a trencher. If you could cope with 3 to 4" wide, then a sharp spade to cut the edges and a grubbing mattock to lift out the waste.

[F Murtz]

???????? this whole thread is??? why make a trench 2 inches wide, there is no known trenching machine that will cut 2 inches, it would be nigh on impossible to cut one 18 inches deep 2 inches wide in soil, this whole thread is weird.

[harry]

It's not practical to make a trench 2" wide and 18" deep with hand tools shit-fer-brains.

[michael adams]

So the penny finally dropped ?

Which is why I'd already suggested digging a wider trench and filling it in afterwards. And all with hand tools.

michael adams

....

[Andy Burns]

Not 18" deep but Virgin used micro-trenching when they installed FTTH around here, basically a twin blade, tarmac-cutting circular saw.

Microtrenching (or slot-cutting) is an innovative technique that can be used to deploy communications infrastructure, typically fibre optic cable, in highways. Under the right circumstances the technique has the potential for low-impact deployment methodology in which fibre optic cable and sometimes conduits are laid into a slot-cut trench less than 20mm wide, and typically between 120-300mm deep, without disrupting or damaging existing infrastructure in the highway. The trench is then reinstated, often making it difficult to even notice that works have taken place.

Or if you can get a tractor in, use a pipe layer

[Tim Watts]

If you really wanted narrower than 4" you could take an angle grinder to a narrow trench hoe and make it thinner - but depending on your soil, it might be self defeating if the sides fall in.

[Thomas Prufer]

Found a smaller unit on youtube -- Terrasaw. Also "Ditch Witch", though those look larger.

Thomas Prufer

[Weatherlawyer]

that were 6 inches wide and up to 24 inches deep. What I want to do now is to create some very narrow slit trenches that can channel water towards th e 80mm pipes.

ches deep. This I would line with permeable membrane and back fill with sha rp sand and small shingle.

line with the blade ie something like a lawn edger with a deep blade. So f ar no luck. I reckon once the side are cut it should be possible to hoik th e soil out with some sort of "L" shaped metal tool.

try a drain ditch spade. Get one from a farm supply shop. Or go to a farm a uction.

[Graeme]

In message , F Murtz writes

Simples. eBay item 122433109719