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Hydraulic thumb

southernman13 · 2015-12-12 07:42

We have a kobelc SK250LC and a Cat 320CL. Was curious what it would take to put a hydraulic thumb on either one. Neither one is plumed for a thumb. At least on the boom their not, I'm not sure on the valving and such. They both have manual thumbs and I'm going to sell one of them so not sure what it would take to accomplish this or if it's worth fooling with.

Replies22
  1. #1roddyo2015-12-12 08:28

    I would probably sell a machine and buy one with a thumb like I wanted. I'm guessing around $25,000 to rig out a machine you have. It was $17,000 to Put one on a 315 a few years ago at cat. I don't know how good a thumb it was or if it needed a valve. I traded with the guy for $20,000. He got a machine over 10 years newer and with 3,000 less hours along with his hydraulic thumb.

  2. #2southernman132015-12-12 08:33

    Well at that rate it isn't an option. Wow that's crazy man!!i don't need one that bad hehe

  3. #3FWD2015-12-12 21:14

    I was looking at 120 size excavators (used) about 10 years ago. I wanted and needed one with a thumb. I found several different brands of good machines but not set up for thumbs. At that time around $10,000 and not a progressive link thumb. I found an EX 120 Hitachi all set up (it needed some pin and bushing work) for not a real lot more. It has the progressive link thumb which I didn't know at the time is what I really needed for my type of work. FWD

  4. #4roddyo2015-12-13 10:32

    This^^^^^^ There is a lot of cobbled together crap out there and at least one instance on this board. If anyone is going to the trouble to mount a hydraulic thumb make sure it mounts to the bucket pin. Progressive link is the best but mounting to the bucket pin will solve a lot of problems. The experts on hydraulic thumbs are those guys in Canada and the PNW, they have been running these things a long time. If one of those members chime in they will give you advice you can take to the bank.

  5. #5Shimmy12015-12-13 13:19

    I agree with half your statement, but not the other half. While mounting on the bucket pin is preferable, it is not absolutely necessary. In my instance, having it on the pin does not work for me. I will not mount/unmount my coupler to take my thumb on and off. I also agree there are some terrible stick-mounted thumbs out there, but mine isn't one of them. I'm not trying to be an a-hole, just pointing out that saying ALL stick-mounted thumbs are junk is incorrect.

  6. #6roddyo2015-12-14 00:16

    Since you mentioned it. When I said cobbled together crap on this forum, it was your thumb I was referring to. That was also one of many posts where I felt you was offering advice or injecting your opinion when you didn't have the experience or practical knowledge to back it up. That also lead to a first for me at HEF, using the ignore function on a user. From occasionally reading your posts in threads I'm involved in, I haven't missed out on much. When it comes to Hydraulic Thumbs, I don't think the entire West Coast of the United States and most of Canada have it wrong. I listened to the experts about 8 years ago and there hasn't been one day in those 8 years that I regretted that decision. Not trying to be an A Hole and certainly don't mean any of this as a personal attack but maybe that will clarify my earlier statement that you seem to take issue with.

  7. #7Shimmy12015-12-14 10:53

    As they say, opinions are like....everyone has one. While I respect your views on a pin-mounted thumb, calling mine cobbled together is a chicken**** statement. Have a nice day.

  8. #8movindirt2015-12-14 13:53

    I gotta agree with Shimmy here bud, going the most expensive and best isn't always an option n'or is it practical, as in Shimmy's case. I've got a stick mounted thumb on our 20 ton hoe and also on a mini hoe, is it the best? Maybe not, but thats what works best for me, I pull the thumbs on and off of these 2 machines so frequently for different applications that it would make no sense to have a main pin thumb. As for Shimmy having no experience or practical knowledge, thats not needed what so ever. Comments like that are better off kept to yourself. Have a nice day.

  9. #9southernman132015-12-14 20:31

    I'm good at coblin things up myself hehe. If it works it can't be that bad. Bottom line right. Post a picture of it so we can see it. I'm all for what works and even more so if it was homemade!! I have manual thumbs on both of my machines now but theyre store bought. I'd like the control of a hydraulic thumb but not willing to go to that expense. These are farm machines not money makers

  10. #10Shimmy12015-12-14 21:02

    $5100 delivered. I welded the mounting plate and tines on.

  11. #11cuttin edge2015-12-14 22:02

    They buy our hoes already plumbed. They had a 320 done after it was a year old, and I do believe it was around $25 000. We have some mounted to the bucket pin, and some with their own pin on the stick. Both work well. They have a home made thumb that they switch back and forth from a 330 JD to a 350. Most of the time it is only put on when the job calls for it. The boys can stick it on in about 20 minutes. A thumb is a handy rig, especially for picking up asphalt and concrete. One thing I don't like about them, and more so on the bigger machines, is loading over a tailgate if you are sitting lower than the truck. I find it gets caught sometimes.

  12. #12Shimmy12015-12-14 22:05

    Sorry, southernman. I wasn't realizing this was your thread. I started with an ACS stick mounted thumb. It comes with 2 tines, mounting plate, and cylinder for $4200. I bought 3 extra tines for $200 each. The round tubing through the tines close to the end was extra that I added as well. I have $5500 into mine, not counting time to build it. Your biggest expense is going to be adding auxiliary hydraulics if your hoe doesn't have it. I've never priced it, but I don't disagree that it might be $10,000. Post your serial number and maybe Nige could get you a part number to check on price. Edit: I would not be afraid of buying one like I built and doing the work yourself. When we bought our 210, Case wanted over $9000 for a generic Werk-Brau, $12,000 to special order to match my bucket. Like other guys (including myself) say, a bucket pin mounted progressive link is the best, but sometimes you have to go with what works best for you.

  13. #13southernman132015-12-14 23:33

    Tenfo that's a nice thumb and a d cent price. I figured the valving and plumbing would be a big part of the expense. I don't know if either machine I have has anything in place. I know they don't have the plumbing on the boom. I'll have to look further into it. Thanks

  14. #14antpoo2015-12-17 08:02

    i bought my thumb from china for $1000. i have no idea how they even made it for that price but i was so happy with it. Fully hydraulic with 90mm pin for 24 tonne JCB. Delivered to Australia. i have had for 15 months now and the only problem has been a nut coming off that allows pin to hang out sometimes. Non progressive link hydraulic is no different from rigid except that you can retract and operate from cabin which needless to say makes life infinitely better.

  15. #15antpoo2015-12-17 08:08

    my China thumb and skeleton bucket.

  16. #16John C.2015-12-17 19:32

    I've installed a number of thumbs on excavators going back to 1979. I hadn't seen the thumb pin mounted on a boss welded to the stick before. I'm sure it works but would be a little leery of its long term life. Hopefully you guys can tell me you haven't had to weld a stick back together after a couple of years of use. I like the quick coupler plus thumb combinations where the coupler mounts to the stick and the thumb bosses are on the outside of the coupler. They stay together as a set and buckets swap on in seconds. The couplers around here are of two varieties, wedge lock and pin grabber. The pin grabbers seem to be the popular units now. The valving and tubes going over the boom are not a problem. I used to buy a four way solenoid valve to work the pilots, a pressure reducing valve to feed that solenoid unit and whatever handles the new owner wanted. The auxiliary control valves were in the machines at that time so you plumbed pilot lines to the spool ends and then ran your main lines from the auxiliary valve up the boom. The switches in the control handles at that time were all normally open momentary units that needed a hot to one leg going in and the other two legs went to the solenoid. Machine control switches now days are PWM type which is a digital unit that hooks into a computer which runs the solenoid so that is probably a lot more expensive. The company I worked for then bought the bucket and thumb combos but at that time didn't have the quick coupler. Bucket and thumb for a 200 size excavator back then was about $12,000. The tubing, hoses, hydraulic valves and labor to install was around $4,000. This was in the early nineties. I used to do the whole install in less than twenty hours. Now days I'm thinking that $25,000 price from a dealer is probably about right. And I almost forgot that I heard the machines sold today don't necessarily have the auxiliary valve when new. You have to buy that as an option.

  17. #17Scrub Puller2015-12-17 20:58

    Yair . . . Thumbs are a rarity around here, the general opinion seems to be they are neither your azz nor your elbow and most blokes don't bother. They seem to run bucket or grapple as needed . . . I can't believe the costs involved. Having said that I recently saw an example of an excellent "cobbled up" thumb on a smallish Sumitomo . . . the feller used it for stacking brush and ran it with a couple of salvaged 12volt power packs. Worked well enough he reckoned and it cost a few hundred bucks in scrap steel and a bit of time. Cheers.

  18. #18Heavey Metal2015-12-17 21:17

    You can make a thumb work just fine with a selinoid valve( with relief) a cylinder some plumbing and an accumulator. No need for any live hydraulics.

  19. #19John C.2015-12-18 00:32

    The old saying around here is "once fed, always hungry". Once you have used one of these you never want to go back to the stiff leg. Around here it goes no thumb, no sale.

  20. #20Shimmy12015-12-18 00:34

    The key is to have one that has a plate that holds the cylinder mount and the thumb mount. That way, the forces applied by the cylinder are transmitted more so lengthwise on the stick rather than pushing on the tube. I've seen pics of the cylinder mount "beer-canning" the stick. Mine uses a ½" plate to hold the pin bosses, and the thumb boss is almost fully over the bucket hinge pin casting on the end of the stick. I use mine as hard as I would use a pin-mounted thumb, have been for two years. Like has been said up-thread, a pin mounted thumb is the best, but my work requires me to take my thumb on and off so often that it just doesn't work for me. I can put it on or take it off in 20 min, quicker if I have another guy to help. BTW, John C, what is your opinion of the thumb that I built?

  21. #21John C.2015-12-18 20:18

    I think what you are describing is somewhat like the machine posted above. I like the 1/2" plate idea real well and don't see any problems with it. We do have contractors in our area that work with underground utilities and the thumb just gets in the way. I think they would be receptive to what you have done so they could work two kinds of projects with one machine. Do you put the pin boss back just enough that the bucket top edge clears?

  22. #22Shimmy12015-12-18 20:23

    Exactly. The coupler hook is what actually interferes with the pin boss. When we welded the plate on, we had the coupler curled all the way in, and set the pin boss about ¾" from the hook on the coupler. I thought about putting it closer, but figured I better leave some gap to allow for wear in the pins and bushings. I would hope I never let the wear get that out of hand, but maybe the next guy might.