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I built a mechanical thumb for my EX 60. I just used a piece of 6" wide (1/2" thick) H beam about 3' long. I welded a 1 1/4" bushing onto on end and another piece of H beam 18" long at the bottom to form a T (this is not necessary and didn't really work well). I made two U brackets(sides about 4" X4" top about 5"x 4") out of 1/4" plate. Cut a couple holes in the sides for the 1 1/4" pin to slide through. Also cut a couple holes on the back side of the H beam abot 3/4 the way down. The last piece was the connecting rod made out of 3/16" 3X4" about (3' long) box tubing. Welded bushings onto each end. Now the fun part. Put all the pins in place and clamp the brackets onto the stick about 6" above the bucket pin. If you measure correctly, the top connecting rod bracket will be positioned the same distance from the bottom pin as the bottom pin is from the pin holes on the back part of the H beam. This will allow you to remove the connecting rod and fold the thunb back up and attach it to the stick if you are not going to use it. This is not necessary and sometimes it is better to take the whole thumb off the stick. Now the part I'm going to be yelled at for. Weld the brackets onto the stick. This will severly degrade the strength of the stick I am told. Your stick will warp, twist, and break, your tracks will fall off and your machine will be worthless. When you get tired of hearing people telling you this, ask a welding supply shop which rods you should use and carefully weld the two brackets on. These welds must be stong, but you don't want to heat the stick up too much- also make sure you get rid of the paint before you try to weld. Or you could get a professonal welder to do it. Either way - it's welded on. I put mine on two years ago and have cleared acres of trees and brush. The only problem I had was the T at the bottom bent longditudnally through the H beam where the blade of the bucket kept closing on it. It eventually bent back and broke through the middle. Now I'm left with just the top edge and it is fine. The main reason I put the T on was to create a larger surface are for ripping out blackberries and brush. For large trees and rocks, I've had no trouble. I have seen no faults in the stick since the weld. I used a MIG to weld mine on BTW. Total cost was about $25, most was laying around as scrap, the pins and bushings were from the ends of worn out augers. Short bushings welded to the outside of the pin holes on the H beam and the brackets would keep it tighter, but I've had no problem with it. I spent a lot of time measuring and making sure everthing lined up where it was supposed to. Took about three hours to complete. I'll try to put a picture on tomorrow if you want. Good luck, Grant
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