Show Me Your 'Thumbs!'

Thanks for the good advice digger dan. I have a good fabricator here who has made one off pieces for me before. I did n't realise any of your fabricators would sell the drawings, i thought they'd be top secret! Great idea, but who's got the best designs I'll try and get a copy?

Here's the thumb on the hoe I use from time to time. I hate direct link thumbs. They're better than no thumb but a prog. linked thumb is so nice to have.

Like the pics coopers, is that a CWS thumb? I like the design.

Here's mine

This is a pin on, and works fantastic. Makes the machine about a hundred times more useful.

Once you use one, it's becomes apparent why it should be built out of the toughest steel you can find. Twisting!

Also, the builder recommended i drop the relief pressure on the thumb to 2500 psi, and it makes a lot of sense. I think the stick would twist before the thumb, so this way the thumb breaks away before anything else starts to yield.

Also, the volvo comes with both foot pedal and electric control for that circuit, so it works really slick.

:drinkup

Eddiebackblade said:

I
It would be good to get a look at the different makes and how they integrate with Quick Couplers.

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I just recently build a mechanical thumb for my 1.6 tonne Kub and the only draw back is that it is hard to see the quick coupler with the thumb on the machine but not a big problem.
I should take some pictures of my set up because it is quite neat in the way it stows away.

I am a small contractor. I have (2) excavators (Bobcat 435 mini-11,00#, & Cat 315CL-40,000#) and both have thumbs. I would not buy a hydraulic excavator without one unless I needed a machine that would do nothing except dig trench. Both units also have couplers (hydraulic actuation). One important thing to keep in mind: The thumb (whichever brand you choose) must be made to work with a coupler (and specifically for that coupler), or for pin on. The thumb is not interchangeable. I suppose it can be done but it won't work correctly. Bucket rotation and the distance between the thumbs mounting pins and the bucket teeth change when you add a coupler. Progressive link thumbs have advantages and disadvantages. The main advantage is that you will get more rotation (out) than with a non-link thumb. This allows you to "grab" things closer to the machine than you can with the non-link thumb. If you have never used a thumb, you won't know the difference. If you have, it can be frustrating when trying to go back to a non-link (for the operator). The disadvantage is that some models don't "stow" out of the way as well as the non-link type. This is not usually a problem except when you are reaching out away from the machine to almost full extension or if you are digging around existing utilities. The other disadvantage is that you have three more sets of pins and bushings to wear out. Furthermore this main link pin is often not visible to the operator (because it's behind the thumb for part of the travel) and if it should come loose, and the operator tries to use the thumb, it will twist the thumb and linkage all to hell.

bigkit said:

Like the pics coopers, is that a CWS thumb? I like the design.

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Bigkit, yes it is CWS. CWS makes great thumbs. I specifically like this thumb they make. I also like their buckets and couplers. PSM also makes a similar product and is also a very good company to look into. Their products looks similar to CWS. I actually had a PSM clean up bucket on in those pics. Coupler and digging bucket were CWS.

PSM is in Washington State, USA. Direct link thumbs in my opinion are a joke with larger excavators. Okay for smaller ones but still a PITA. Stay away from CP products. Horrible designs.

Check out Loewen equipment. They make a pretty neat quick attach thumb set up.
http://www.loewenequip.com

Look under the for sale section.

great idea with the teeth!

quick attatch thumb looks pretty cool,i havent seen one yet im gonna chk out that site

I am enjoying the input from all on the whole thumb issue.:thumbsup

Firstly I haven't had time follow up Rocklnd on the Krypto Claw yet, but shall do so. It would be good to get some pictures and input from a real user on here though.

The latest idea from Lowenequip of a Hitch/Thumb combo is quite inspired also.

I enjoyed the post from DGODGR, all very good information for us 'Non Thumb' operators.

I know it's a bit sad, but I have been keeping a sort of mental note of how a good 'Thumb' set up would fare against my current 'Engcon Tiltrotator and Selector Grab' on clearance work.
I am fairly convinced that obviously each has benefits, but a Thumb set up would be very low cost (by comparison) stronger,lighter and much less chance of being damaged.

That's obviously not detracting from the outstanding ability of a Tiltrotator and grab, but I'm certain all will agree where any work involves clearing timber and brash then strong and simple is the way forward.

Eddie

I was not thinking of your tilt rotator when I made the reccomendation against the Klaw.

It would be the ideal match with the rotator, as the thumb part is always aligned. It would work good if you have good proportional E/H control for the aux curcuit it would work on.

I love a thumb, and the idea of one I can turn whichever direction works best just blows my mind.

Hi everyone,new here. Looking for thumb on mini-excavator,either to buy or plans to fabricate. Takeuchi TB-035. Any ideas would be helpful,thanks.

Maybe this thread is dead, but if not I also would like to know if some brands of thumb are better than others, or is it just important to make sure you purchase a hyd. thumb with progressive linkage. I am currently pricing a thumb for a 35 metric ton machine. Thanks.

When i bought mine i didn't know anything about them. So i asked around some of the excavator dealers, and they told me who to avoid. There are some manufacturers that make cheaper units intended for the auction market. Those have a tendency to disappoint.

After seeing the twisting forces applied, i'm glad i went with a unit with a good reputation.

Mine is built from 100% AR400, designed specifically for my machine and bucket. Works great and very strong.

hows this?

Watglen,

Thanks for the input. Sounds like everything, you get what you pay for, and if you pay more, there is usually a reason.

Hydraulic thumbs

How do the hydraulic thumbs work, are they on an electric circuit? I've only been around the stationary ones, and they're a pain to use.

Eddiebackblade said:

I am enjoying the input from all on the whole thumb issue.:thumbsup

Firstly I haven't had time follow up Rocklnd on the Krypto Claw yet, but shall do so. It would be good to get some pictures and input from a real user on here though.

The latest idea from Lowenequip of a Hitch/Thumb combo is quite inspired also.

I enjoyed the post from DGODGR, all very good information for us 'Non Thumb' operators.

I know it's a bit sad, but I have been keeping a sort of mental note of how a good 'Thumb' set up would fare against my current 'Engcon Tiltrotator and Selector Grab' on clearance work.
I am fairly convinced that obviously each has benefits, but a Thumb set up would be very low cost (by comparison) stronger,lighter and much less chance of being damaged.

That's obviously not detracting from the outstanding ability of a Tiltrotator and grab, but I'm certain all will agree where any work involves clearing timber and brash then strong and simple is the way forward.

Click to expand...

Hey Eddy thumbs are great when you do a lot of demolition type work or land clearing work as you can grab a larger amount of material when your loading out trucks. But one thing to note is that there is a large weight penalty, especially with progressive link thumbs. I do a lot of work with tilt buckets and find that thumbs just get in the way when I'm doing shape work and can make the machine more tippy when the bucket is full and I have to reach out to a truck to dump it. A few years ago I was digging a basement next to a demolition site cleanup. The company there was using an old Hitachi UH-181 and the operator there was a bit of a backyard fabricator and had built himself a thumb setup similar to the "krypto claw" and he said he preferred it over conventional thumbs as he could take the whole thing off much more easily and not suffer any big weight penalty's when using a breaker (which are pretty heavy) or using a larger sized bucket for truck loading dirt, gravel, etc. Here's another one called "powergrip" I've never used it myself but its a pretty clever design kinda like a 4 in 1 bucket for loaders.

http://www.helac.com/construction/powergrip.asp

Hope this helps

Hi Coopers, sorry its been a long time hope you're well! Things have been busy here but I'm back on the thumb thing. Can you tell me what the approximate ram size and the stroke is on your thumb on the 120 if you've got time please? I'm going through a creative phase...........

Thanks in anticipation........