sanding blocks

well i dont like dura block at all and i was looking at asf block and i took a jab at making my own...

I took aluminum I beams 3X2.5X0.15 and ripped them down the middle and mil the surface to make sure it was true and flat. Then I took some 1/8 in EVA foam for backing glued it to the I beam for adhering the sand paper to the block.. for $90 bucks I got a 4", 6", 8", 2 12", 2 16" , 24", 36", 48" blocks the 36" and the 48" block seems to be working really well for the long panels on my a body..