Art Mateials Pet Peve

Hey, forgot this yesterday when stretching the canvas.......ever notice how art materials from different manufacturers are not compatible to one another?  It really torks my engines when I go to stretch a canvas and I only have two bars from one company and then two bars from another company and they wont work together because they have the slot on the opposite sides of the bars from the other company's slot.  It's as if they go out of their way to piss me off.  So I am now having to order more bars from company A, just so I can use up those last two bars.......OH, and even worse, some companies will not let you order less than 48 stretcher strips, claiming they will get broken in transit if shipped in small quantities.  Guess what two bars will get used as tomatoe stakes this spring?????