How to trench

June 3, 2010 3:44 PM

I'm seeking advice about using trenching machines: Soliciting all advice, suggestions, anecdotes, warnings or information about using a trenching machine. I’ve never used one before.

The fellow who cleared out some trees for me strongly advised using a sit-on rather than walk-behind unit.

I will have about 500 feet to traverse, some of it clear and some of it where there is likely tree roots and/or unknown buried debris. The location was a local dumping ground in the past.

On the plus side:
I will have the help of my nephew who knows much about machinery; so am hoping there will be an innate ability to trouble-shoot any machine malfunctions.
I’m willing (gullible?) to tackle it and am not afraid to get grimy and sweaty.

posted by mightshould to home & garden (10 answers total)

Is there any possibility you're working near buried utilities, old tanks of any sort, or unstable ground?
posted by Inspector.Gadget at 3:48 PM on June 3, 2010

Yes know full well about ANYTHING underground, even abandoned stuff. You may hit something anyway, so operate the machine in that "defensive" mode.
posted by Danf at 4:08 PM on June 3, 2010

Be safe: wear boots, long sleeves, long pants, gloves, and goggles.
posted by Carol Anne at 4:16 PM on June 3, 2010

if you are going more than two feet deep make multiple passes to get there-its safer.

Call the Call before you dig people for your location-if you don't know the number call the public works department of your local town and ask them for it, and pay attention. If you manage to hit a utility line without getting this step done you will pay for all repairs and it ain't cheap. It can run multiple 100k for hitting a fiber optic line. if you do need to dig next to a utility line dig by hand till you find the line and mark around it, don't get anywhere near the line with equipment.

If you are really worried about metal in the ground (I would be from your description) use a metal detector to remove objects from you path.

And lastly if you decide it is too much for you, just hire someone to dig the trench than you do all the other work. its way cheaper than a visit to the emergency room for a severed foot or buying a trencher you ruined from the rental place.
posted by bartonlong at 6:29 PM on June 3, 2010

Following up on what others have said: Make sure there are no buried "anythings" utility wise. You'd be surprised at what you might find while digging a trench. Especially in places you think no one would be inclined to bury things.

That said.

Get a riding trench machine if at all possible. Might not be possible, but it is well worth the extra money spent. Walk-behind trench machines will leave you feeling as if you were repeatedly crushed by pro linebackers all day after 500 feet.

Trench machines are very basic so if your nephew has mechanical ability he should be perfectly fine were any issues to arise. Anything more than that would be beyond the scope of fixing in the field anyway so not to fret.

Ohh and as Carol Anne said: Wear your PPE. Personal Protective Equipment. :)
posted by Gravitus at 6:34 PM on June 3, 2010

Depending how deep your trench is, be sure to brace it even though it takes more time and effort. Digging someone out of a collapsed trench is a nightmare--for you and the rescue crew.
posted by MsKim at 8:09 PM on June 3, 2010

Be sure to cross-check estimates from an excavation (if it's deeper) or landscape (shallower) company. Occasionally I've found it to be cheaper to bring in the professionals than it is to rent the equipment, especially if you give your time any value at all. Sometimes contractors like to fit in small jobs in between larger ones just to keep crews busy, and will bid them cheap as a result.
posted by Forktine at 9:46 PM on June 3, 2010

Good thoughts. Thankfully, there are no underground utilities in the area. From previous digging, there may be buried broken up concrete and metal scrap in one location. I'll try and determine this before going in with the machine.

A riding machine is definitely in the cards for me. Since I have more time than money, and love experiencing new tasks, I'd like to do it rather than hire it out - but I'll check contractor pricing as suggested.
posted by mightshould at 5:18 AM on June 4, 2010

I used a trencher once - walk behind, not riding. Worst tool experience of my life. The thing was as big as a quarter horse but for some reason trenched as well as a butter knife into granite. Your experience may differ, but a large job like this is almost always going to be safer, and turn out better, if you hire an excavator for a couple hours. You could at least get an on site estimate first. And figure it'll take twice as long as you expect.
posted by docpops at 10:19 PM on June 5, 2010

Results:
The Backhoe
The model we rented was a Toro dingo stand-on type trencher. It featured rubber tracks that did not cut up the surrounding ground (which also did not provide much traction.)

Project:
The ground covered was predominately level with a few steep inclines. Soil type was sand/clay mix.
We totaled 6 operational hours on the machine over two days with an accompanying heat index of 102ish F. Each day, we spent about one or two hours planning and moving any obstacles. I’d estimate we trenched a total of 900 feet, maybe a bit more. The machine used less than 5 gallons of fuel.

Assessment:
Go slowly as the machine doesn’t really power it’s way; instead it chews it’s way through.
Operate the machine in reverse – forward is mainly useful when grinding back and forth through heavy roots. Develop eyes in the back of your head for optimal ease of use.
Wear hearing protectors and glasses as the unit is noisy and kicks up lots of dirt.
Gloves are recommended.
The steering handles are easy to understand and use, but are sized for a man’s Medium size hand. If yours is smaller, expect lots of hand fatigue.
The machine vibrates a lot. This translates into aching joints by the end of the day.
Good/gullible friends are a must. It’s best to have someone walking nearby looking for anything the operator may miss.

Feasibility:
Yes, this is something that’s not too difficult. But, it takes time and is exhausting.
A walk-behind machine looked to be much more difficult to maneuver and would have made the task overly tiresome.
posted by mightshould at 8:54 AM on July 2, 2010