PRO-GRIP 90 DEGREE HEAD BY PEACHTREE WOODWORKING PW569

It simply is not 90 degree. It sits tight on the groove at the bottom. There is no movement. still it is not 90. there is no scope of moving and setting it to 90 as the two runner sit snug on the groove. Bad design. I am back to checking square everytime I use the straight edge clamp.

This accessory reduces the clamp capacity on a 24" clamp to 23.75". For the price it should be gold plated and NOT reduce the clamp capacity. very poorly engineered.

I agree that the clamping face of the 90 deg Head is not molded square to the two rails which get pushed into the aluminum clamp extrusion. When you push the rails into the extrusion you find that it is a very snug fit, with no wiggle room to adjust for the lack of perpendicularity. I put the Head in a vise and used a 10" file to angle the clamping face to counter the misalignment. It was a bit of trial and error, but I finally got it right, and now I have a 90 deg Head that works as advertised. Now that it's properly aligned, I find that it works very effectively to consistently line the clamp up at 90 deg to the work. I gave 3 stars because, even though it is a good idea and now works very well, I shouldn't have had to file it into proper alignment to make it work.