Backhoe Thumb - Which pin to use?

[Johnny Glenn]

Thanks for looking in - I've got an 88 Ford 555B and I'm trying to add a backhoe thumb. I've heard you can add an extended boom/bucket pin to attach the thumb but was wondering which pin? Would it be best to use the bucket pin or the pin that hinges bucket movement? Thanks and any other advise or helpful links on a "thumb project" is greatly appreciated!

 

[Johnny Glenn]

I decided to weld a plate to the boom instead of trying to use pin positions.

I'm working on an 88 Ford 555B - a medium sized backhoe - Anyone have an idea on high far should the second support plate be positioned? The (first) plate/pin is located at base of boom where thumb hangs from but trying to figure out where to mount the (second) plate - the one that has different pin positions to change angle of thumb. Thanks

 

[SixHoeBob]

Bottom pin should be about 4" above the primary bucket pin, and welded to the tractor side of the dipper boom. The top pin should be about 24"-30" above the bottom pin. Cut templates out of plywood to determine the design of the thumb. Drill 1/4" holes to represent/locate the pin hole centers.