Howdy Folks. I will candidly admit that I only have limited experience with both units. I operate heavy equipment as it pertains to ranching: loaders, skidsteer, tractor trailers etc. I am constructing a feedlot and properly running waterlines in a farmyard I have purchased. It will involve trenching thousands of 8' deep waterlines up here in northern Saskatchewan. I am wondering what unit is best suited for this task, an older backhoe or a smaller trackhoe? the land is a mix of sand and clay without much for stones. I can backfill with my loader so I am only interested in the unit as to its trenching ability. Your experience and thoughts are appreciated. My budget is $15000-$20000 Cdn. Thanks for your time.
My choice would be a (trackhoe) excavator. Eight feet deep in sand,clay and a mix will require a sewer box or a good job of sloping the side walls. Otherwise someone will be killed or injured when the trench collapses. I am including a photo of a sewer job being done the safe way.
The advantages of a backhoe are cost, versatility, and speed moving around. It seems that none of those would help you if you have a trailer to haul an excavator and a loader as well. You only need to slope the sides or use a trench box if somebody will be in that part of the trench. Slope the areas where you have to go down to connect joints/hydrants/waterers, and then fill the pipe with water so it will lay flat in the bottom of the trench, but not pulled tight, leave a little slink in it. I put it against one side of the trench, and backfill from the end of the trench so the dirt slides down the slope onto the pipe rather than falling the whole height of the trench onto the pipe.
Excavator would do that job in a 1/3 of the time which would save you a lot of money towards fuel.
Thanks for your advice. no trench boxes required as we will not be in the vast majority of the trench and will slope sides where we work in it. i forgot a key point, what size excavator are you thinking of when you suggest one?
3.5t+, bigger=better. Digging thousands of feet of 8' trench with my 6t (Kubota KX57), wouldn't be much fun, but it would be a decent paying job!
20t. And for anyone looking at the picture of the trench box, that won't hold up in a court of law should something catastrophic happen. Nor will it protect a persons life should the worst occur. Last I knew a trench box is required to have at least 18" of box ABOVE the edge of the trench. Sloped back to whatever the soil classification dictates. Also the box is supposed to have no space between the side of the box and the side of the trench. Should a cave in occur the box can tip to the side, pinning or harming the employee in the box. Please don't take my comments as condescending or insulting, I am just trying to help prevent anything from happening to anyone. I have sat through countless hours of O.S.H.A. training and seen to many gruesome pictures and read to many write ups of accidents that could have been prevented through proper training.
I would also recommend using a 20 to 25 ton excavator for several thousand feet of water line 8' deep . Damn it must get cold up there to need 8' depth . This outfit plows it in https://www.youtube.com/watch?v=Ic1YS5pv4FY
This Year 8 foot might not even be enough, I have a 8 ton machine and could easily do 8' deep.
They're freezing the pipes in Minnesota that are 8 feet down. Coldest I was in was 23 below zero; it hurt to breath it was so cold.
With wind we have seen in the -50's a few times and weeks of -40's were I live they cant keep up too frozen and broken waterlines this year and it's still early.
Lockhart You might have to bump up the budget a touch. As Delmer said if you don't have a trailer to haul an excavator the rubbertire backhoe would be my bet .But no dout in my mind the excavator will work best .I have both backhoe and excavator and I love the tractor backhoe but when comes down to the big business we bring in the excavator and the backhoe comes in behind for clean up.
Yeah ... It sure has been a long winter . I reckon that's as much of an issue as the temp itself . The length of time a cold spell lasts driving the freeze deeper in the ground . I think the coldest we have seen this winter in south IN was -12F then it would hang at or a little above 0F for 2 or 3 days , then back to say between 15F to 25F for the rest of the week. I remember back in the early 1990's we did see - 20F during a cold spell . Most of our water lines are 3 foot in depth and for the most part that works fine for my area. I have ran across private water lines going to the customers home that were only about 16 inches deep . As long as they were under fescue sod they seem to do ok . When there is no top cover to help insulate like at road crossing can be a trouble spot for freeze . We also make damn sure to let water run slightly at the faucet during & after a cold snap . Seen a lot of lines freeze while its thawing out ,be warm on top & muddy at the surface and the freeze still driving deeper . You know... I guess another option for the 8' deep water line rather than open digging it all up would be to directional bore it . We see utility companies do this all the time on fiber optic when they don't want to deal with an open cut . Don't know if that would be a cost effective option or not :beatsme
My choice would be a 20 ton excavator. Thousands of feet at 8' is a lot of time and hacking for a rubber tired hoe. JMO
I would recommend either a 6 or an 8 ton mini excavator. I have dug 17 feet deep many times with a 3.5 ton mini. Any thing deeper than 17 feet is to time consuming and next to impossible to dig
where does a rubber tired excavator fit in the picture? I envision it has greater mobility than an excavator (which would be nice) but greater dig capabilities vs. a backhoe. are there pros or cons to these units? here is something similar to what I am describing http://www.marketbook.ca/listingsdetail/detail.aspx?OHID=9351013&LP=MAT
It will work, but they are not as forgiving of inexperience like a tracked machine will be. If you don't have any seat time with one I would suggest something else. I've had them on 2:1 slopes, in mud over the top of the carbody and balanced on 2 tires, they will do amazing things. However for your needs go find a nice old Cat 225 and start digging. Stay away from a mini, you'll just be pissing up a rope for those types of footage and depths.
people seem to mention a 6 or 8 ton excavator else they opt for a 20 ton unit. what about something in the middle? I am envisioning a 12 ton unit like a Hitachi ex 120-5 http://www.marketbook.ca/listingsdetail/detail.aspx?OHID=9472349&LP=MAT seems reasonable value.
Im A big fan of www.rbauctions.com , you go go to the nearest "yard" to inspect and bid or do your bidding online... I live down the road from the prince george bc auction site, but have also been to the chilliwack auctions and the original site in surrey bc...canadian company and if im correct the largest machinery auctioneer in the world. As for your excavator/backhoe dilemma, Im a big fan of the rubber tired hoe, BUT in your case (Im also a farmer/rancher) an excavator up to a 12 ton would probably the most "economical" for you...a 20t will do it but is overkill due to the narrow trenches you require... my neighbour runs a 12t case excavator and uses it all over his 2500 acres cattle operation ditching,stumping and burying water lines and electrical. Were now looking at a joint purchase of a 30t processor unit to clear 200 acres of his and 60 acres of mine... Ritchie bros. is where i will be watching for possible candidates...
Trencher
Yeah jdm , a tile trencher with a boot might be an option . This model has 6 foot depth www.dktrenchers.com/specs.html Lockhart76 needs 8' depth . Another possible issue he mentioned in the first post is the ground is a mix of sand & clay so I would think on an open cut using a hoe a fella will have to do a lot of over dig with a wider trench to prevent cave in's . This would make the chain trenching option using a tile boot look even better . Just have to find one that would go the full 8 foot deep .
Ok, for those suggesting a mini hoe, yes it will do it. But its the optimal machine? If your talking anything under 6ton in mini excavators, I'll take a big backhoe and smoke you. Why, you don't have the reach to dig that deep effectively, anytime your in deeper than 1/2 your stick, your not making production. With a mini your moving every 4' and set up again. Idealy you want anything from a 160 - 210 if your the one paying by the hour. If I was buying a machine to have around for the purpose of this water line and general maintence, a 4x4 full size tlb with cab & extend - a -hoe would be the ticket. Or if I wanted something for just trenching, the 160 is the go to size.
If I was in your shoes with your budget I would be more concentrated on nice solid machine, as opposed to a machine perfectly matched to this particular job. If you narrow your search to the perfect type of machine and end up with a old, beat, high hour machine, you may spend more time and money working on it. Obviously a 20ton ex is going to trench faster than a 7-8ton backhoe, but not if you spend half your time wrenching on it. So I would patiently shop for a solid machine with a open mind on the exact type and manufacture. I completely agree with stump jumper, a mini ex for this job seems like a bad idea. I would much rather have a TLB on this project than a mini.