How to Install a Mechanical Weld On Excavator Thumb August 19 2016, 0 Comments


Install of Mechanical Thumb for Komatsu PC50uu

At Frato Products Inc. we manufacture , install and repair equipment attachments for the Construction, Snow Removal and Waste Industries. Our Frato Excavator Thumbs have quickly gained traction and many of our customers have been requesting install instructions for their machines. 

We built and installed a 36"x7" Mechanical Thumb for Carl's Paving on their Komatsu PC50uu. Adding a thumb would make driveway tear outs and asphalt removal much faster allowing a more productive work flow. 

Check out all of our Thumb Attachment products for Excavators and Backhoes at

Excavator Thumb Install Instructions

Step 1: Prepare Surface area of Machines arm and mounting bracket. Make sure to grind them down to bare metal for welding.

Step 2: Set mounting bracket by positioning excavator bucket to full curl while placing a 2x4 under the mounting bracket between bucket top to make sure it has enough clearance when bucket is at full curl. Use a C clamp and clamp the bracket in place.

Step 3: Make sure the clamp is centered on arm with same amount of space on each side of bracket. Place and Level on top of Mounting Bracket to make sure it is straight. Then tack weld the bracket in place.

Step 4: Assemble thumb before fully welding bracket to arm. Verify that everything is inline and positioned correctly. Once verified remove thumb part and arm from bracket.

Step 5: Pre heat welding area with torch to allow for full penetration . Fully Bead Weld the Sides and Top of Of Mounting Bracket and Re assemble Thumb. 

This entire process typically takes between 40 minutes to 1 hour depending on the experience of the welder. We suggest painting any exposed welds to prevent rusting. If your in the North East Ohio Area feel free to bring your machine by and we'll handle the install for you. If you have any questions feel free to drop a comment below.