I'm cutting a fire break near the house. Under two feet of top soil is mainly serpentine (a soft, decaying rock) that breaks easily under my excavator 18" bucket teeth (11k pounds of break force at the bucket curl). I have hit a few areas that I would consider Igneous rock (like granite right in picture) that is very hard and some large boulders. I've tried to work around these. At what point will I damage or break my bucket teeth by scratching away at these hard rocks with a tooth or two trying to widen my path? Common sense tells me to not tackle rock that doesn't easily break on first draw--unless I can dig it out as a single piece. Is there rule of thumb that would let me know if I'm pushing my machine too far when trying to break through rock areas? All advice appreciated. Thx Allan
When your machine starts lifting, jumping around, dragging its own weight forward. Back off.. Grab a narrower bucket if you have one. I have a ripper I use for hard stuff, then I bail it out with a dig bucket.
I think generally if you have the forged one piece teeth the hydraulics will hit relief before the teeth break on that size of machine. Something else could break though if you pry too hard or have the stick extended out too far. I pulled the top swing mount off on my backhoe trying to pull up frozen ground. I wish a tooth would have broke instead. It also bent the lower swing mount that was 1-1/2" thick. Luckily I was able to fix it myself but was a big job. I figured having to hire someone would have cost $3000+. Had to use some pipe to line things up initially and then had a piece of tubing machined for final alignment of upper and lower pin bosses. Thankfully there was a little clearance up and down and it went back together.
I worked for a decorative rock outfit that shipped decayed granite to Phoenix from a permitted site near Kingman. Because of the fragile nature of the rock product (weathered decayed granite) I loaded the flatbeds with a 30 ton P&H Omega. The crane needed an access road from working radius to working radius. I could usually load about 3 trailers before I had to advance the crane. This required pioneering about a quarter mile of "cat" road a week plus crane pads. Depending on the density of the available material that needed to fly. As I produced the road and crane pads I would load out a truck with material I could reach with the excavator. This project required some pretty serious excavation in places of granite bedrock. Which initially proved not doable with the EX 200. I stopped by a bar, out that direction where people in our industry would get together for adult beverages... after a 300 degree day. I related my pioneer issues to a guy I talked with sometimes and he told me to get twin tiger teeth and that they would dig it. So I did. Called the shop and the wrench sent me out a full set Hensley Twin Tigers. They will dig granite bedrock. The fracture was good and didn't beat the day lights out of the machine. They were about 35 dollars a throw for a full rack. In the most brutal rock I have had to dig ever, ( my highest respect to AzIron!) they would last 35 to 40 hours generally. Occasionally much less or much longer depending on the hardness of the bed rock. When the teeth stopped cutting I was done until I replaced them. The excavator held up fine. I had no issues with it. However I was the only operator. Not that I am any great wizard of excavation. I'm not. However... I always keep in the forefront that the machine I am running pays for our groceries, car and house. I treat them as valued partners. Not to be abused or treated like a sledge hammer. Good Luck with your project.
Just dont pry with the bucket and you will be fine. Teeth are a wear item and are expected to be replaced.
Push the teeth into the rock like you bite with human teeth. Catching the teeth under ledge & prying with the bucket curl is a whole lot of stress. Over time the weak point will fail. Often a ripped open bucket. Consider adding material to cover the ledge, or cut away ledge with a diamond chainsaw. You show a sidehill cut over a gentle slope. Move the road farther to the downhill side. You want a sideways pitch in such a road to discourage rain from running down the road. Rainwater should flow off the road to one or both sides.
This is what can happen when you pry on rock
Changing the direction you are digging many times will make it easier.
That rock got really hot!
Been there, done that. A while back I started a thread where I jumped the gun in March digging out a stump with a 12" bucket. I ripped the whole bottom out. Replaceable teeth are considered expendable. The rest of the bucket is not. No big thing to learn the hard way if you are a capable welder. If you need a professional to do it for you, it'll get expensive! I always preach there is no such thing as too big a machine. The big machine sells for a little more money than the little one, but it is tougher.
I ran a Volvo 88 in Mount Rainier National park, and it had essentially the same mounting hardware as a 35 wedge lock manual change bucket. The mechanics welded it a few times for me. I was being careful and could still tear that bucket apart. I really liked the machine, it needed a pin grabber and some tougher buckets to be great.
I have seen plenty of torn up little buckets and big buckets. Just dont pry with the bucket and you will be fine. If you bend or break a bucket on that machine just pulling then the bucket was trash or worn out.
I've done that to a bucket or two...
Wille B are you saying I can tear teeth off a bucket or tear a bucket up on tree roots? I have been using my smallest bucket (18" with teeth) to dig out 12" to 24" Oak. I have to fight some of these if the roots are thick. I've been slicing away on the roots with the teeth. Sometimes it makes the entire excavator jump a bit. Am I on the edge of breaking teeth or a bucket? I always thought that steel would win over wood.
A ripper is a far better tool to use for getting stumps out. They will cut through the lateral roots easier than any bucket.
IF you are slicing the roots, you won't break your bucket. You can shave your way though really massive roots, as long as you can do it across the grain.
Just dont pry and you will be fine.
Glad I could make the cut on that note there is disable rock its usually in a form of cleach or granite around here and not all veins are created equal fractured rock is usually the worst to try to dig cause as it flakes apart it wedges up and eats shanks. MD is right twin tigers in my experience will be the thing that gets you through digable material the best I have 2 buckets sitting under my shade right know one with busted shank the other a cracked frog from digging in rock and that's on backhoes and that is not in extremed well the rock was hard but we had the hammer out and a green operator I am training ate the shank cause he didn't know when to back off the frog is on a bucket I hit an electric line with a few years ago that blew a shank off I think that fatigued the metal On 2 occasions I have seen a tooth failure both were do to the retainer pin bending or falling out beat on rock is hard on pins to it bends the snot out them also digging rock is just abrasive and will flat wear out a bucket not to mention you can wear out a set of teeth in less than a shift We had a job years back we changed teeth every morning and at lunch granite was to tight to dig and to soft to hammer just had to grind it out
In my case, the stump had grown in a rock pile. It was impacted in the rock. I got in a hurry & tried to dig it out when there was still some frozen earth. Yes, I tore the bottom off the bucket. You can take it easy & not damage your bucket. To dig a stump, widen your circle. dig farther away from the base of the tree. Break the roots where they are smaller, then work your way toward center. The teeth are wedges. press them straight into the tough stuff. Do the ripping with the dipper crowd, not curling the bucket.
I found pictures:
I will heartily second Tones recommendation of a ripper rather than a bucket for digging stumps (& rock). I used my 24" bucket for a while....then I got a ripper...what a difference on stumps!! The ripper concentrates all your power on the very tip!!! But get a good ripper, or you will "rip" your ripper. I would recommend my Werk-Brau with an Esco UltraLock pick tooth.
yes it was trash all right it was too light! you could absolutely damage it just digging straight away with no prying. I'd never seen that situation before where the bucket was visibly just not enough. Really like the excavator though.
If you use common sense there is nothing wrong with a bit of prying with the bucket, I do it with both my hoes and never had a issue with a bucket. You need to make sure they are properly built for the size of machine and in good shape. If the bottom tears out, either it was too light of bucket, or it was fairly well worn and weakened. I do agree on the ripper though. I built one myself for my 6 ton and it's been a lifesaver for big stumps and frost ripping. I also pry with it and abused it pretty good and it's taken it well.
There are times I would like to have a ripper.
Making the coupler is the only hard part. You just need a heavy piece of steel for the shank, or I welded a bunch together. I have wain roy so while the coupler sucks making it for an attachment is super easy. I've pried like heck on it and it won't budge. But then again the shank of it is 6.5"x2.25" I don't think a machine twice the size would be able to break it. I welded 3 5.5"x0.75" pieces together and put 2 0.5"x2.25 pieces the other way on both sides. Then buy a nosepiece for a single tiger tooth and weld it on. It doesn't have near the ripping force my 210 does, just because while the tooth is a fair bit smaller it can only get so small and still be strong enough to take the force. But even in hard frozen ground 3' it'll work it's way through it.
Any access to a Machine with a hammer? (Hydraulic Breaker) The are a necessity out here. All we have is rock with pockets of dirt. If you expose your entire break and see what you would need to hammer then break it up and send the hammer/machine back and dig with your machine. A 2000-2500 LB hammer works wonders.
If you can dig it then just dig it. Work your way around the rock and dont pry with the bucket. You will be fine.
I have a ripper for my 5 ton E42 and it will do a great job of digging up rocks unless it's a solid shelf. However, we don't have granite rock, it's mainly limestone which is fairly soft. If your granite rocks are in bits and pieces a ripper should work well.
But you can pry with a descent ripper without any problems and still have a bucket in good nick for the next job. Simples.