wolf44
Well-Known Member
After looking around and getting prices on thumbs I came to the conclusion that thumb manufactures are on crack. Way out of line on prices. So I started to design and build my own progressive thumb. Here is the steps I have gone thur so for in my design build. First my machine is a Kubota KX-71-3. I started buy taking pictures and getting dimensions of the stick and the connection links and the pin sizes. One of the problem that I began to notice when I started looking at thumbs was that they were either to small or to large or they welded on and had poor travel amounts. My other excavator is a Cat 312-CL with a hydraulic thumbs which has always irritated me that the thumb travel was less than I would like, so when I got the little mini I was determined not to have that problem.
The first thing I did was make cardboard cut outs of the stick and the bucket and the control link and the H link and to work out the travel and the pivot positions. after the card board cut outs I made aluminum mock ups to test and refine the pivot positions and linkage shapes and thumb detail. Then on to the solidworks cad program to design the part for flame cutiing.
The first thing I did was make cardboard cut outs of the stick and the bucket and the control link and the H link and to work out the travel and the pivot positions. after the card board cut outs I made aluminum mock ups to test and refine the pivot positions and linkage shapes and thumb detail. Then on to the solidworks cad program to design the part for flame cutiing.