I am bidding the site work for a new credit union. It is 50' x 127' with a 14' basement. I need to dig 13' to the bottom, plus I need to over excavate another 7' more because the soil underneath is unsuitable. I then need to import and compact modified to bring it up to grade. Soil engineer wants a overdig of 5' past the footers. Therefore, I will be digging 62' x 139'. All material has to be hauled off site. The site previously held a nursing center that was demo'ed and backfilled with fly ash. Therefore, I will have to slope the banks for safety. I was orignally thinking about renting a 300 size hoe, but I am second guessing myself and I am leaning towards a 400 size. I priced out a 1 month rental on a Cat 330 and it was $9,500. I can get a Volvo 330 for $8,700 and it is brand spanking new. I haven't priced out a 345 or EC460 yet. What do you guys think ?? I know mobilization will be alot more for the 400 size hoe.
i say a 300 the 400 may be too big for its own good, and slower besides you can only move your material as fast as your trucks can move it
do you have to do it in one cut or are you going to mass ex and then go after sub -ex ?if you do it in one cut,i would want the reach of a 345,if not a 330 with a big bucket.if you go with cat try to get a c or d model in my opinion.
Im a fan of bigger then needed machines on site. I would use a JD or Hitachi 450 decent cycle times can load trucks fast so pour them on. A wrist bucket might also help speed up cuting the slope.
i am running a hitachi 450 LC with a 4 yrd bucket,first time i've ran a late modle hitatchi,decent machine has some nice creature comforts.
we are only talking 6400 yards, with a 400 yeah you will not have to move the machine as much but if you can only get 10 trucks a day out period that little bit extra the 400 will give you isnt worth it. the whole job depends about the trucking, dollars and cents the job depends upon the most economic way to do it, i dont see the need for a whole months rental regardless if just for this one excavation. If Rino was using artics or site trucks maybe or maybe just bail the daylights out of the foundation and stockpile then load out at your lesiure with a machine you own while you are waiting for the foundation to get formed poured and stripped.
I'm with you Pecord. Without seeing the job its hard to comment, but the only reason you need that size machine is the digging depth. You can't possibly keep it busy on this job, you just can't get enough trucks moved into and out of position to keep that monster digging. Better to use a smaller machine, do the job in two cuts, and spend the savings on more transport, cuz that's where it's needed. Keep us posted, good luck.
What is the trucking situation like? You could go with a 270 sized hoe, have the performance of the 330 and the dig depth and still be lighter on fuel and rental costs. Also whats a big hoe in your area? Who has a 450/345 thats maybe sitting around not moving much. Might be easy enough to rent the larger hoe for half a week from someone else if they wanna see some rust come off the bucket. OR... if I may add some humor to the thread. Why not be a man about it? YouTube - CAT 5110B loading trucks
Now your talkin Alex!!!!
Thanks for the input fellas. I just completed the bid today and gonna type it up. They are due Monday. I figured on the 330. Total excavation comes out to about 8,700 yds with the slopes. As far as renting someone elses hoe, there are 10 GC's bidding. I am willing to bet that every excavator in my area is bidding this job. It is complex, wall footers are a certain thickness, inside wall footers are a different thickness and piers are thicker. I need to also take a mini down inside and dig for the footers after I bring modified up to subgrade.
I am confused Alex. Are you recommending that I rent the 5110 or hire the white hat taking the siesta ??
I suggest you rent the 5110, I don't suggest buying one. Think about it, you'd only need to rent it for a half a day lol.
330 size machine TOPS , the number of dump trucks and distance is more important then the machine loading them! If your hauling 25 miles and only have 3 trucks thats a bunch of idle time! If there is no big rocks you could get a way with a large bucket on a 30,000 ~40,000 lb excavator. Is water a problem ? if it is your in for a good time! that big of hole will be full every morning , more wasted time!
Geo-tech report says no water, but we are near a river, so we shall see. What will be fun is that there is a old concrete foundation underneath that we have to include removal in the contract. Knowbody knows what is underneath. Previous building was demo'ed and backfilled, hence the unsuitable soil.
If you are moving 8,700 yards the difference between the 330 & 345 will be noticable. Trucking is important in the bigger picture but is not the factor. If there is room on the job, you can stage the trucks so that you are not waiting for them to get into position. This puts production rates all on the excavator. The size of the site indicates that you shouldn't have a narrow loading zone and it shouldn't take that long to move into position anyway. There is a lot of info that's missing (if it was my decission) to make the right choice. Can you get enough trucks to keep the machine moving? What size trucks are you using (this will help determine how many excavator cycles it takes to load them)? Do you have enough room to keep up production? Do you have over head considerations? How many yards per day must be moved to meet your required production rates? I would tend to think that the 330 would be a little more versatile (better for finishing your slopes and such) than the 345. Many of your questions (about production rates) can be answered with a Cat Performance Handbook (available from a Cat salesman).