I went to use this clamp recently. Either the plastic was brittle, or I squeezed the handle too hard. The part of the handle that adds pressure to the clamp broke in my hand. I decided not to discard the clamp and get a new one, but to make a new squeeze handle and continue using the clamp. The photo shows the break.
Step 1: Tools and Materials
Angle grinder with a cutting wheel
1/8 x 3/4 inch strap iron
7/16 inch rod
The photo shows part of the broken handle that will be used for a pattern. In my hand I am holding a piece of 7/16 inch steel rod I have ground away to copy the half-round portion on the broken handle. After grinding, I used a hacksaw to saw two cross section slices from the rod. It was necessary to cut a triangle to be welded to the 1/8 x 3/4 inch strap iron.
Step 2: Weld Both Halves of the Handle
The two halves of the squeeze handle I made are shown here welded. Compare the cavity in the blue handle on the clamp and the broken portion of the original handle. I have ground the welds a little to make them nearly flat. There is some free movement in the clamp for the handle, so the welds do not need to be completely precise and smooth.
I cut and ground away some of the triangular pieces welded to the strap iron to fit the cavity in the blue portion of the handle. Notice a chalk mark on one piece and a score mark where I began cutting on the other. I did a little grinding for making a close fit.
Step 3: Test Fit
Insert the welded pieces of the replacement handle into their place in the clamp handle to test the fit. Pay attention to the angle of the welded replacement handle pieces. I had to grind the round 7/16 inch rod a little on one of the replacement pieces to make both pieces follow the same angle of inclination coming out of the blue section. I probably did not have the half-round pieces positioned identically when I welded them to the strap iron pieces, or the flat portion was not identical on both.
Step 4: Weld the Squeeze Handle Pieces Together
There are three pieces in the replacement handle I am making. Two have already been shown. The third is a flat piece that makes a bridge across the front of the two already seen in earlier steps. I welded the flat piece to one-half of the replacement squeeze handle using a piece of aluminum angle to hold the pieces while welding.
Unfortunately, the replacement squeeze handle cannot be attached to the clamp after all welding is finished, but the final weld must be done while the replacement handle is on the Irwin clamp. Fortunately, a spring clamp held the pieces for the final weld as shown in the photo.
Step 5: The Final Result
The new squeeze handle works as it should. Here I am holding it with some pressure on the squeeze portion of the handle. The Irwin clamp advances and tightens just as it did before it broke.