In another thread I saw talk about progressive v Direct link thumbs and although I know the difference and will outline it below for those who don't, I was wondering what the advantages and disadvantages of each were and where one should be used over the other etc. Thanks. For those who don't know a progressive link them looks like the excavator bucket look up like this... A direct link thumb is real simple you can see pictures of both. http://www.accuratefabricating.com/products.htm
Thumbs The progressive link thumb will have more range of motion, and therefore be more versatile. It will also move out of the way more when not in use.
http://imac.ca/products/bucketclamp.htm I would agree with dirtworks but also the progressive link mirrors the follow up linkage on the bucket and allows the object to be gripped through a larger range of movement than the direct link. I would guess that the direct would be more suited to occassional use but the progressive would be better suited to accurately positioning logs, boulders etc.
:iagree i agree with your explications wulf.A progressive thumb is suited for finish positioning landscape element but also for handling large material such demolition debris.In my opinion,i prefer the progressive thumb,more precision in handling operation but a direct thumb is also good.
Getting a direct link Getting a direct link for my PC75UU-2E. Dealer offerer a thumb that pivoted on a bracket off the stick, but i elected to source one that pivoted on the bucket pin.
Also with a progresive the thumb cylinder remains closer to the stick which is useful in not bending the ram while loading trucks.
Oops! Still should turn out OK! Oh well! My new direct pin thumb interferes with the existing bucket. USA Attachments is being great in the way they are handing the fit-up issue. Rather than heavy rework of the thumb and bucket at $85/hour shop rate at my expense, they are providing a new bucket at minimal cost. In the winter I will rework the old bucket and slightly rework the thumb to fit the old bucket, which I will use as my rock bucket. RC Hazelton's have been understanding working with me on this also. See attached posts.