We have three Universal I presses in our printshop and a number of the plexiglass dust covers have cracks from use. In the past, I had tried fabricating covers, but they never came out with the correct angle. So, I decided to do it right, and make a ‘buck’ to drape the heated plexiglass over.
I first drew a template of the inside curve of the broken Plexiglass dust cover and cut it out of book board. I then made five more for the uprights of the ‘buck’. Then I glued support pieces of cut book board held together with Elmer’s glue forming a honeycomb structure. (I should have taken a picture of the internal structure).
Then, when I thought it was strong enough, I glued a bottom and back piece, also made of book board. The top was made with a thinner book board and glued over the honeycomb structure to form the rounded ‘buck’.
I then used a sheet of 13” x 23 1/2” piece of 1/4” thick plexiglass, which I placed on top of a hotplate turned up to 500 degrees. I also placed a sheet of plywood on top to add weight and increase heat retention. When the plexiglass was soft to the touch, I draped it over the ‘buck’ and clamped it in place until it was cool. I wore heat-resistant gloves and worked quickly, making sure the plexiglass was square to the buck.
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Well done, Gunars.