Our patent pending premium adjustable stack pin is a must have. This adjustable stack pin will completely eliminate slop in the frame stack connection point. It eliminates slop both side to side and vertically. It's as if the two stacked sets are welded together... that's how nice this stack pin truly is.
Use it just as you normally would. Insert into bottom frame. Insert a pigtail, toggle pin, span pin, drive pin or cotter pin with cotter key. This secures the stack pin into the lower set of scaffolding. Next stack your set on top. Now secure it again with your choice of above just mentioned. Now all you have to do is tighten the bolt as seen in the pics. This will move the two clamshells outward and press them against the inside of the vertical scaffold tube. It eliminates all slop and movement. I don't know about you but that's what I want. No movement or as little movement as possible.
Word of caution: Do not overtighten!! Hand tighten then a quarter turn further is all that's needed. Overtightening can split the tube. It's not needed. We lineup our vertical tubes with seam inward toward the horizontal's to cover the seam with a weld from the horizontal to prevent splitting of the seam. This prevents the bottom of a 5'X5' frame for example which does not have a horizontal within 1/2 inch of the bottom of tube like the top of vertical tube does. Long story short... Don't overtighten!