Meade ETX-60 Telescope Rear Port Cap

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Had to fabricate a rear port cap for my ETX-60 telescope. Threads are reportedly 1-3/8 at 22 threads per inch, and the iso tap tool in Tinkered came remarkably close, allowing the part to thread all the way first time. This is only 1 millimeter thick, with walls measuring 1.5 millimeters. The height is 7 millimeters, so the inside depth is roughly a quarter of an inch. Location is the straight-through rear port underneath the eyepiece on the ETX-60. Alternative options include remixing with increased thickness to the base, adding a 38-millimeter disk to the bottom for any desired thickness and adjusting your fill accordingly. The disk is translucent at 1 millimeter, posing little concern at night in the dark environment. However, a thicker back or wrapping in painter's tape and spraying the inside with rust-oleum flat black primer proves effective, as seen in the photograph. Just ensure it dries overnight to avoid flaking off when screwing it on, which is preferable to sticking from wet paint.