Help with mechanical thumb

[jb1390]

It's not mine but is in the family. I won't be making this change many times probably. I'm sure the plan is for the thumb to be in the widest position all the time at the farm.

The thumb looks like it's floating but it's got a stop for that position. It looks like it was made to sit just like I have it. There is a tab on the back side of the thumb to hold the thumb bar back against the stick but there is a bit of a gap so it would clang around. I'll find something a little more robust than that old strap to stop the clanging when it fails. I'm mostly loading trucks with driveway shale and going to do a little re-grading around the lip of my pond, so I don't want to fight the thumb the whole time. After doing it the first time I should be able to do better in the future. A lot of the issue is a result of the slop after 5,000 commercial hours. It's in great operational shape but the pins and bores on it are tired and loose. Also the thumb is so heavy there is no way the pin is going to slide unless I get the weight off with the bucket and it's hard to get just right without putting it in a bind the other way.

Yep I hear you on the weight. Having a second person helps, to be able to wiggle the pin while someone is making a fine adjustment. Otherwise you have to run back and forth to the controls. With some practice it's not bad, I'm sure it'll be easier the second time.

Have fun with the machine! It took me a little bit to get used to Cat controls on mine, I learned on backhoes. Mine does not have a pattern changer on it. I thought about changing hoses but wanted to keep it standard. So now I'm halfway decent in the excavator and can't run a backhoe smoothly anymore lol.

 

[LittleBittyBigJohn]

This is the only hoe I have ever run. I got enough hours on it digging my pond I'm probably to that dangerous level of competent, where I think I'm a professional but I still don't know what I don't know. I doubt I would be able to hit the ground with a backhoe if I ever run one. It sounds like the stick and boom are on opposite hands with a backhoe compared to track hoe?

 

[jb1390]

This is the only hoe I have ever run. I got enough hours on it digging my pond I'm probably to that dangerous level of competent, where I think I'm a professional but I still don't know what I don't know. I doubt I would be able to hit the ground with a backhoe if I ever run one. It sounds like the stick and boom are on opposite hands with a backhoe compared to track hoe?

Exactly. With Cat (Excavator) controls the boom is push/pull right hand, and stick is push pull left hand. Backhoe (Deere) controls the boom is left hand, and stick is right hand. Swing is left/right on left hand for both, and bucket is left/right on right hand for both.

Where it messes me up is when you're running multiple functions. Like when you're trying to cut flat, you pull both sticks towards you, then relax on the boom as you hit right angle but keep the stick moving. It's so easy to release the wrong hand. When someone that's used to running Deere runs my machine, I get a good chuckle now, because I know what they're going through.

LetsDig18 is an excellent channel on youtube, he's a very good operator. However, he has a video titled backasswards excavator controls, where a long stick he was renting was plumbed in Deere. It's an entertaining video.