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Alan64

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Everything posted by Alan64

  1. After the three screws shown above were sawn shorter, all three sets of hardware were installed... The extensions are now completed. Next, I will need to matte-blacken the hardware on the inside, along with other related areas.
  2. To ensure that the bronze-veneered extensions do not pop off in future. these parts are for securing same to the optical-tube in the highly-unlikely yet not-impossible event that the epoxy fails... Note how one side of each of the nuts has been filed down, and so to clear the flange of the primary-cell.
  3. The three, new mounting-screws for the primary-cell have been cut down, and to where they just barely "peek" out past their jack-nuts...
  4. I was only wondering as to the nature of that Opticstar diagonal. I then found that it uses a mirror. You can use a star-prism instead with your 70mm f/13 refractor. I have the Celestron version of your telescope... I've used a Celestron star-prism with that one, and with my other refractors. A prism is more durable, and with less light-scattering when viewing brighter objects. This is the diagonal... https://www.365astronomy.com/Celestron-Diagonal-Star-1.25-in.html You have to be careful when selecting a prism-diagonal, as there are the Amici erect-image types, and the star types. That Celestron is a star type, and best for use at night, as is a star-mirror. In that the Opticstar contains a mirror, then I assume that it is a star-mirror, and will serve. The diagonal that came with your telescope is an Amici erect-image, and best for daytime/terrestrial use; birds in trees, ships at sea, that sort of thing. You can use it at night, but on the smaller, brighter objects you may see the "Amici line" of the prism, and as an illuminated streak across the objects...
  5. Your 127mm Maksutov may function as a daytime/terrestrial spotter, for birds in trees, ships at sea, that sort of thing, and where you'd want the image to be upright and corrected for left and right. For that, you would need a 45° Amici erect-image diagonal; for examples... https://www.firstlightoptics.com/diagonals/skywatcher-45-erecting-prism.html https://www.365astronomy.com/Baader-Amici-Prism-45-degree-1.25-inch-with-24mm-free-aperture.html However, when the telescope is aimed at the sky, it doesn't matter if the image is upside-down or whatever, for which a star-diagonal will serve, unless you want the view to match what you see on a chart, map or app. In that event, you'd want a 90° Amici erect-image; for example... https://www.rothervalleyoptics.co.uk/antares-90-erecting-prism-125.html With any Amici erect-image diagonal, you will see the "Amici line" illuminated when viewing smaller, brighter objects...
  6. Still doddering along I am...piddle, pitter, putter... That's more like it. In that the primary-mirror will be moved forward by the thickness of a toothpick, combined with limited range of the low-profile focusser, the ability to adjust the cell accordingly will be there if needed, albeit way-overkill given the effected range of adjustment.
  7. With stainless-steel flat-washers integrated, the screws for holding the position of the primary-cell during collimation hold fast when battened down; delightful. However, now I don't want to use Phillips-type screws for this. Instead, I will be heading to my local hardware for hex-key screws rather, yet similar to those. The Phillips-type will be fine for the cowling at the front, as they will be battened down once and forgotten. I could go ahead and flock the tube, but I really do want to wait until I get the cell sorted out.
  8. "Dust" of steel, to bolster the J-B Weld, and thereby the extensions to the tube...
  9. I had forgotten that recesses into the cell had to be made, and for each mounting-hole extension. Those are now done... Now I may J-B Weld the extensions onto the tube...
  10. A home-repair/replacement project reared its ugly head... ...hence a delay, but not for long. I decided to go with a two-handle for the kitchen this time round. Plumbing is yet another of my specialties. The optical-tube was masked off... ...then glossed for the flocking... I may now J-B Weld the primary-cell's mounting-hole extensions onto the tube...
  11. I had no trouble with this 70mm f/13 achromat's tube... ...nor with this focusser's drawtube... Come again?
  12. I wouldn't say better; easier, rather. Unless of course there'd be a pressing need to remove it in future.
  13. I finally got round to removing the bulk of that sooty black paint lining the optical-tube. It was a right good finish, wonderfully flat and of a deepest black, but the interior must be glossed, then flocked...
  14. The lamination of the extensions with bronze, and with J-B Weld steel-reinforced epoxy(made in Texas)... A clamp of oak, hard-felt and wax-paper... Double- and single-sided clear-tapes were also utilised, and to prevent shifting of the components... <tick-tock, tick-tock, tick-tock>
  15. The tube's substrates for the extensions were stripped of paint, roughened in the process, and to be scored... From my humble sheet of phosphor-bronze, three sheetlets... ...which were then sanded with 80-grit paper and scored on one side...
  16. This is only a test-fitting, and to illustrate precisely what I'm after...
  17. The mounting-hole extensions were given a final shaping, sanding with 80-grit paper, and were then scored on both sides; one side for epoxying to the optical-tube, and the other for the epoxying of the phosphor-bronze sheet thereto...
  18. Why, they appear as soda- or beer-can pop-tabs; splendid. In the end, those will be overlaid with a "veneer" of phosphor-bronze.
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