Does size matter?

[Digger293]

Hello everyone........I'd like ask a question thats been bugging me for a long time. Is a 66 inch severe duty bucket to much for a new PC-400 with a long stick and long boom???? I tried to argue about it with the owner of my company but he didn't want to hear it. I told him that the machine was slower and that it was rocking around to much during high speed production (digging/loading end dumps) Notwithstanding it was killing my neck and back. He responded as I thought he would by saying that I was probably to heavy handed on the controls. I've never been heavy handed on the controls. I also had the highest production rate of all the excavator operators. The machine was new when I got it and came equipped with a 58 inch bucket. The machine was really smooth and stable and could could fly. I believed I moved the same amount of dirt or more but I could not get him to switch back to the 58 even after I told him it was beating up the machine and of course less important to him, my neck and back.......Is it me??? I checked with a dealer rep. on the sly and he told me the bucket was to big with the long stick/boom combo.

 

[digger242j]

I really don't understand what the problem is. :beatsme



But seriously, I don't know the particulars of PC-400s and their bucket sizes enough to make a qualified comment, but just because it'll mount to the machine doesn't necessarily mean it's the optimum bucket for the application. You already mentioned beating up the machine. Are you getting a full bucket on each cycle? Does it take as long or longer to get that full bucket? Longer cycle times or less than full buckets negatively impact production. There's more to it than just mounting the biggest bucket that'll fit.

Feel free to print the picture of the mini mass excavator and show the boss, if you think it'll help make your point. (And not get you fired...)

 

[Wulf]

Diggers,

The product brochure for the new PC400 which you can see on the Komatsu website will show the recommended bucket width, empty weight and capacities (cubic yard) of a Komatsu bucket coupled with boom and arm type. This is a good guide to match after market buckets with. If the parameters are exceeded when matched with the weight of the material handled you could be overloaded.

I think instability and tippiness is often a symptom of mismatched bucket or attachment and because the cycle times are very fast the dynamic effect can make the machine uncomfortable and less productive because you have to go easy on the levers to control the machine.

Also... you didn't say exactly how old the machine is but warranty could be questioned if something fails with the machine equipped improperly

 

[digger242j]

I took a quick look at the Komatsu website before I posted that, and didn't see the product brochure specific to the PC-400, but did look at the product list of crawler excavators.

The PC-400 family has:

PC400-7 246 330 41400 1.3 - 2.2
PC400-8R 257 345 41740 1.3 - 2.2
PC400LC-7 246 330 42850 1.3 - 2.2
PC400LC-8R 257 345 42740 1.3 - 2.2
PC400LCSE-7 246 330 44190 2.8 - 3.2

Those numbers are horsepower, weight, and bucket size in cubic meters. Again. I'm not familiar enough to know the differences.

Good point about the warrantee.

 

[Digger293]

Yeah 242, the bucket was full or heaped every time which made the machine rock due the dynamic effect at speed that Wulf mentioned.....I was able to dial it down after a while but not totally. I'm not a complainer by nature but at the end of the day I was getting pretty twisted out....couldn't wait to shut down. I was amazed at how the slighted rocking motion for 8 hours can effect you physically. Well, I think in the end my health and my "credibility" was taking a hit and it was making me question my abilities.....Thanks for the help..

 

[Wulf]

Digger... Here is a link to the page on the public website:

http://www.komatsuamerica.com/viewchart.aspx?prdt_id=937&chart=3

The weights referenced at the bottom mean material weight you are working in. The codes mean whether its OK or not... Z = not recommended etc..

 

[digger242j]

That's worth posting here directly, Wulf. I'm sure Komatsu won't mind.

I circled in red all the combinations that are "not useable" (Z).

Looks like the 66" bucket is only useable with the shortest stick, and light material.