Estimates on footage an hour.

[biggixxerjim]

Some guys Im working with are starting a new job (largest solar instalation in the northeast) and there's going to be some underground runs. I am going to be renting 2 5 ton mini ex's (either case or komatsu) and was wondering how many feet you guys think I willl get in and hour.

The ground is a soft shale to red clay, dont really think Ill be getting into rocks at all. Trench depth is to be 3ft, and will be 4ft wide, digging with a 2 ft bucket.

I am a very experienced operator (10 years) but havent done a lot of estimating. Im guessing about around 100- 125ft/hour.

What you guys think??

 

[joispoi]

What are the site conditions? Can you dig your trenches without interuption? Who else is going to want to be where you are at the same time? Who is going to expect you to ''hang on for a little bit while I......''

You´re renting 2 machines. How many cigarette breaks is the other operator going to take. How many phone calls is he going to get?



Check your estimate against what the production manual says the machine you´re going to rent can produce. When using the manual, the time listed is optimum performance. Then you have to factor in what the human performance is going to be....(just a guess) maybe only 80% of what the machine is capable of.

Don´t forget to add a clause to your bid that allows you to charge extra if you hit obstructions: ledge, large boulders, buried cars or bodies.:drinkup

 

[CascadeScaper]

That sounds about right. When I ran a 50 sized Yanmar a couple years back for my buddy, I could do 60-70 feet per hour of 3 foot deep trench with a 2 foot bucket in good to sometimes tough conditions.

 

[Hendrik]

Why not get a bigger machine with a 4 foot bucket instead of two smaller ones?

 

[rino1494]

I get about 110'/hr with my 315 at 3 1/2' deep. That is only 1 bucket width wide. Production with a mini digging 2 buckets wide will be slow.

 

[biggixxerjim]

hmmm. 110 in an hour on a 315... so much for my extimate!!


I have to use a smaller machine because I have pile driven beams that are 16 ft apart that I have to dig through, as well as the faact that Im going to be using it to set frames for all the panels to sit on (24'x8', 400lbs.) 1400 of them to be exact. Thats why were getting 2 machines.

I only need to dig 4ft wide for a couple hundred feet, the rest of its small quarters digging

There will be no obstructions rolleyes as we are digging in the middle of a field. Noone in the way either.

 

[Cat420]

If I may throw another wrench into the mix. I used a Case cx75 which is a little heavier than your looking for, but may apply to others in their line of mini exs. I don't know if it had a problem or not, but even with under 100 hours, it had the slowest swing of any machine I've ever been on. I vividly remember sitting there waiting for it to swing over to dump. Otherwise good digging power, so I don't think it was bad hydraulics.

Except for a pc21 Komatsu, which got its bucket stuck in the ground from suction, I've never had a bad day on a Komatsu. They always had an excellent balance of all functions and just worked like you expected.

All that to say, make sure you give each machine a try before you try too hard to figure its production.

 

[Aardvark]

trenching

don't know if its any help but I excavated 120 metres by 1metre depth by 300 mm width in a day and a half digging at an average pace on my '98 Hitachi ex58mu in fill ( lots of sandstone ghoulies) that had been well compacted with a d9.
By the same token I excavated 60 metres by 2 metres depth by 300mm in 3 days on my takeuchi tb015. material was compacted fill for 1st metre and clay for 2nd metre
cheers mate

 

[jjmcnace]

hmmm. 110 in an hour on a 315... so much for my extimate!!


I have to use a smaller machine because I have pile driven beams that are 16 ft apart that I have to dig through

Our Kobelco 210 will fit through a 12' wide opening. Also with a bigger excavator you could switch to the narrower bucket when you don't have to be 4' wide and it will have much more power for faster digging.

 

[biggixxerjim]

Ok plan revised. Gonna get a PC 150 with both a 2 and a 4 foot bucket to do the main digs, and then a pc 80 to do the 2 ft laterals close to the buildings with.

then gonna keep the 150 to set racks with. these racks are 24'x8'. and weigh in at 400lbs. On second thought, should lifting and setting these rack be a problem with the 80, as far as reach goes?? Im pretty sure the weight wont be a problem.