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4.5 Inch f4 ASTROGRAPH – Assembly Required

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I am selling my 4.5-inch f4 Newtonian Telescope. I used it to do astrophotography for the past three years. The only reason it needs to be reassembled is because the original tube was damaged. I purchased a new solid, spun-aluminum, tube to replace the old tube. The optics are very good and the new tube is much better quality than the original tube. I disassembled the telescope and have not put it back together. The primary mirror and the oversized diagonal mirror, for astrophotography, are in excellent condition. The parts have been safely stored for months. In the meantime, I purchased a larger aperture scope online. I am using it to do astrophotography and don't know when, if ever, I will get around to reassembling the 4.5-inch scope. If you are interested in buying the parts, and assembling it, you will have to do the following: Drill the holes in the new tube for the spider diagonal, the focuser, and the primary mirror holder. All of these must be aligned and installed very precisely. Two other things I need to mention. I was considering purchasing a better-quality focuser for astrophotography. I am including the old focuser I have been using as part of this package, but it is not what I had planned to continue using. Now is the time to upgrade the focuser because once you drill the holes in the new tube, it is permanently modified for that focuser. Finally, the primary mirror cell mounting disk is slightly too large to fit in the new tube, by about 1/16th of an inch. This is only because the thickness of the walls of the new aluminum tube are slightly thicker than the original rolled steel tube. The outer diameter of the aluminum tube is the same as the original tube so the telescope mounting rings fit perfectly. The spider mount fits perfectly and the inner cell that holds the primary mirror will fit inside the tube with room to spare. The mounting disc that supports the primary mirror cell is about 1/16th of an inch too large in diameter to fit inside the new tube. I had planned to cut a 1/2-inch-thick wooden disc, 5 1/4 inches in diameter, and drill three holes, through which I could insert 3 longer adjustment bolts that are attached to the inner cell and that hold the primary mirror. The inner mirror cell would be supported by 3 strong compression springs and by 3 bolts. This is probably the simplest solution to fixing the problem. Lastly, the new aluminum tube needs to be painted flat black, at least on the inside, before the telescope can be used in a practical way. Provided are pictures of the telescope parts I am selling and a couple pictures that I took through the scope when it was assembled and working with the old tube. The picture of the Andromeda Galaxy is a mosaic of four images.

Included parts are: 4 1/2 inch f4 primary mirror, mounting cell for the primary mirror (needs to be modified: read details), diagonal mirror for astrophotography, spider mount for the diagonal mirror, 2 inch low profile AstroSystems focuser, 5 1/2 Inch diameter Aluminum Tube (3 1/2 inches extra length for Astrophotography), mounting rings for the telescope tube, and 8 Inch Vixen-Style dovetail bar.