looking at the Esco and WB they attach the pivot linkage of the stick with a welded on pivot pin spot, others fasten outside of dogbones on that pin, what is better if you have used both. thanks
A thumb that is utilizing the main bucket pin will have more rotation than a thumb that has its own lower mount welded to the stick just above the main pin. A main pin thumb is also somewhat easier to install since there is less welding, even though you may still need to weld on an upper mount for the thumb cylinder for both versions. The only real downside of a min pin thumb is if you do a lot of trenching with a skinny bucket, the mounting ears of the thumb may stick out and rub the sides of the trench.
Take a look at this ProLink. I had one put on my 160. I really like the design, been excellent and it was thousands cheaper than WB. https://solesbees.com/product/hydraulic-progressive-link-thumbs/
Only progressive link thumb I've had is a Cat thumb on a 321CLCR. Worked great but it was heavy.
sorry I need to clarify, there are two types that I have seen, to get the extra rotation of a progressive, the linkage is spun of the dog bones or a attachment that is on the stick,these of course are all running a thumb that attaches to the main pin I would think the dog bone style would be tougher anybody try the stick attached style
The Solesbee I listed gives you a 180 degrees of rotation. Used it on numerous demo projects, solid design. If you do any amount of serious thumb work, prolink is the only way to go.
checked out the prolink,looks like the piece from linkage to thumb is two inches thick, just one piece to, so less points to wear, looks very nice!
I put a Blue Star Welding progressive link thumb on my 304 and couldn't be happier with the ease of installation, quality and most of all, functionality. https://www.bluestarweldingllc.com/services/buckets-attachments/
blue star is nice, looks like it tucks away nice and close to boom,
The Blue Star is especially nice in that it follows the bucket to within about 3 inches of a fully open bucket. Very handy.
Anyone use an AMI thumb? Letsdig18 Progressive Link Hydraulic Thumb - AMI Attachments® The Custom Edition LETSDIG18 - Progressive Link Hydraulic Thumb provides more constant pressure throughout the entire cylinder range. The thumb achieves more than 180 degree rotation which makes it easy to reach and pick up objects that are close to your excavator. www.amiattachments.com