Been pondering this for a little while now. Talked to a few people about it and got a couple of different answers. Just thought I'd see what the general consensus is here. We bought a 2006 Hitachi 270 last Dec. and have been using it a little bit off and on since. One thing I've been wondering though is how most people use their thumbs. I'm wondering if you are rolling the thumb into the bucket to pick up something or if you're rolling the bucket into the thumb to grab what ever it may be that you're picking up. In theory the relief valves should protect everything up front(ie thumb stick linkages bucket) but stuff does happen. That's the only reason I ask.. Couple of pics. Anyone from Alberta know or recognise the contractor? They're from Thorsby Ryan
I use the thumb crowd most of the time except for fragile stuff, that's when i crowd the bucket into the thumb very nice machine by the way. :drinkup
Just depends on what you're doing I and which was the pile needs to move to be better grabbed. It's not unusual to use both on the same grab.
Thanks, it's our first excavator so we're learning as we go. Looking forward to moving some dirt with it this spring. I've never dug with them yet so it's all going to be a learning experience. Should be a fun one though hopefully. Machine has a few hours on it but I think it's been well taken care of. We got all the service records with it and they spent a fair bit just in maintenance while they had it. Everything is nice and tight and the pumps seem strong. Will lift itself all the way up at idle anyways. I've found that it's much easier to grab onto something with the bucket but I try to avoid putting to much pressure on the thumb. Noticed that you don't seem to get as much clamping pressure with the thumb alone as you do curling the bucket in. Just want to avoid damaging anything. One thought was unloading logs off the semi if we get in a pinch. Haven't tried to pick up any logs yet though so I don't know how well it will work for sure.. Need some more practice first anyways.lol.. Ryan
I've seen a lot of work done with a fixed thumb when needed it to pickup piled vegetation. You have to pin them up and pin them down manually. Works pretty well but is a real P in the A, so a hydraulic thumb must seem like it was sent from Heaven. Then again, I know a clearing contractor who does not have a single excavator with any type of thumb. Nothing to break down or create wasted time or smash fingers.
If you're nervous, check the pressure relief setting on the thumb. Powering into/through the thumb with the bucket shouldn't be a problem for it. It's also no big deal to coordinate the bucket and thumb to roll in or out while holding on to the load to gain extra reach or more favorable positioning. Also there are times when it would be helpful to push with the thumb by itself. That's not a problem either.
Depending on how your thumb is plumbed, sometimes when you're going for smaller items that might be tougher to grab, using the bucket to roll into the thumb is typically easier. Auxiliary circuits seem to be hit and miss for smooth proportional flow, therefore the ability to feather the thumb is usually more difficult than it is to feather the bucket into the thumb. I know the newer machines are getting better and better but most of the hoes I've ran, it was always easier to feather the bucket. Again, depends on the machine, how it was plumbed and possibly all the way down to switches on the joysticks. Some are proportional sliders which is pretty slick.
Depends on what I'm trying to p/u. If it's green waste, brush etc. I will let the thumb do its thing. If it's rock boulders or something delicate, I "get it close" via positioning my thumb, and than curl the bucket in. The hydraulic flow in the bucket seems to be lot more gentle going to the bucket, than it is to the thumb. Depends on the excavator though. My little "Cat" has a thumb that's not very forgiving. She clamps fast and hard. On my 50 zts, the thumb is lot more gentle.........
If the thumb is properly setup the bucket will overpower it. I always set the thumb circuit line reliefs to 2500 or so.
It's going in the shop hopefully this week so I'll see if I get time to check it. Got a couple of oil leaks to try and fix up and going to change some oils while it's in there. Just kind of want to go threw it to learn more if nothing else. I picked up some power poles with it yesterday. First one got made into firewood though.lol..I brought the bucket up to the power pole and then brought the thumb down to it. I let go a little bit early but there's a slght delay from the time you let go of the button to the time the thumb quits moving. Just enough to snap a piece off the end of the pole that I was grabbing. Next ones I positioned the thumb and curled the bucket into it and it worked like a charm. Lesson learned I guess.lol.. Thanks for the replies Ryan
Yeah,I guess Heavan hasn't arrived yet for me.Manual homemade thumb on my 410G hoe,but there's hardly anything I can't do with her.It's all about mind over matter--run with what you have.