This is a shot of the rack I made many moons ago. You will need at least 4 spreaders to maintain equal distance between the ends. I use simple screweyes on the end and attach my plugs to them. To eliminate sag I use a spring on one end. I also use a swivel on one end and that allows the plugs to turn easily when applying the epoxy.
You will love the rack, takes the worry out of saggin epoxy.
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