Work with roller glass cutter will be much more accurate if the basis for such processing, as shown in the figure.
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For setting up a small Christmas tree to make the d-pad is not a problem. I set out to build a universal that is not dependent on the thickness of the barrel. Took two cut a metal...
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Sandpaper glued to the plate, to help clean the soldering tip on the scale and layers of soot. And put on the skin of the pieces of tin and rosin help both obludit sting. Y. Zhdanov