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Alan64

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Everything posted by Alan64

  1. It's a shame that I can't make another washer smaller than this one(58mm x 55mm)... ...but I may have a use for that centre portion in future, for whatever that might be, resting there within a crystal ball.
  2. I would think that placing a small radiant-heater, like that for a chicken-coop, would be an ideal, and with an adjustable thermostat. You wouldn't need a lot of heat.
  3. Now on to next order of business(busyness): the RA setting-circle assembly; the assembly consists of the primary dial; glamour shot... ...and the secondary dial... ...albeit my sample with a broken screw, but no matter, as we will soon see. The reverse of same... Note the three clear-plastic washers; combined, they are 0.039"/0.97mm in thickness, but no bronze washers to be made there. Note also the triad of "cushions" round the centre. That part, however, is dispensable, utterly useless. The inner portion, with the three foam pads, is intended to hold/stabilise a polar-scope which is no longer extant; this one... When I bought my Celestron CG-4/EQ-3 back in 2012, I got the polar-scope for it, too... That's Celestron part # 94223, but it will not fit my LX70/EQ-5. I would need part # 94224 instead. The Sky-Watcher polar-scopes for an EQ3-2 or EQ-5 are the same, and made by Synta as well. The polar-scope for an EQ3-class mount-head screws ONTO the rear of the RA-shaft... Conversely, that for an EQ-5 is screwed INTO the rear of the RA-shaft... I make mention of this as there has been considerable confusion online as to which Synta polar-scope fits which Synta mount. Perhaps now the confusion will come to an end. Whilst there is the Celestron polar-scope, "tried and true", there is also that by Astromania, for an EQ-5, and reputedly with a more accurate, precise reticle. The two reticles compared... The Astromania polar-scope is also 33% less in cost, and for which I have already placed an order. This is the order for assembling/re-assembling the RA setting-circle for an EQ5-class mount-head... Fairly simple, eh? But in my case, I'm going to have to figure out how to enhance the assembly. I know of at least one bronze washer to be incorporated, and perhaps a second once the polar-scope arrives. To top it all off, the cap for the polar-scope, and the RA-screw... Said screw is much mysterious. I'll have to research that. The cap; glamour shot ... Have a look at this... That's a bit of thick felt there, a small bit, and I'm rather surprised to see it included, but I'm going to replace it with considerably thinner flocking material, as the cap fits too snugly, making it difficult to place. I may be able to flock it all the way round, or at least halfway round, and for an improved fit. We'll see.
  4. Only if you have no other choice. Like if you're in the middle of a desert, with no car, no internet, and the local trading-post carries only that. Otherwise, it's best to avoid eyepiece/accessory kits. You really only need a 32mm Plossl, for your lowest power. Then, choose a 12mm, and a 2x-barlow. With just those three, two eyepieces and a barlow, you will have these magnifications at your disposal... 32mm(20x, and binocular-like) 16mm(41x) 12mm(54) 6mm(108x) I have the same 20mm that came with your kit. It's an Amici, erect-image eyepiece... It's primarily for use during the day; birds in trees, ships at sea, that sort of thing. It can be used at night, but unsuitable in the end. It came with my Celestron "PowerSeeker" 127mm f/8(f/4 or thereabouts natively) "Bird Jones"... Eyepieces are the whole other half of a telescope kit. You can't use one without the other, imaging notwithstanding. Else, separately, they'd be useless, bricks. It is for that reason to choose your eyepieces carefully, slowly, one or two at a time, and tailored to your telescope, yourself, and the objects you'd like to see. Incidentally, ALL brands of 1.25" eyepieces and accessories will work with your Celestron telescope. There's no need to acquire only those branded "Celestron".
  5. The moment of truth arrived... Success... The DEC clamp-lever gets ever so close to its fitting, but not quite; in its hard-locked position... Disappointingly, the RA-clamp, when unlocked, rocks back and forth a bit; slop, and has all along. I was hoping that the thinner "buttons" would improve that, but no. So, I took a piece of 0.005"/0.127mm thick aluminum sheeting, and lined the fitting's threaded cavity from top to bottom, halfway round. I then screwed in the brass clamp-bolt all the way down, then out, and the shim conformed perfectly. I then applied a liberal amount of grease to the fitting's and the brass bolt's threads... I would've loved to have shimmed it with the slightly thicker bronze, but forcing the bronze to conform might damage the threads of the aluminum fitting, or the threads of the brass bolt, or both. I'll play it safe for the time being. That's something I would need to test, but not on this mount-head. The result? In its unlocked position, the RA-lever does not rock in the slightest. I don't think that the brass bolt, moving such a short distance, will chew up the shim over time. But time will tell.
  6. The thinner brass "buttons" were dressed and polished... Aren't they even lovelier, now that they're svelter?
  7. I sat the fence of the saw a frog's hair over 4mm from the blade, 4.10mm to be exact... I certainly didn't want them any thinner. They must be of some substance, else they'll compress and wear away into nothingness, not to mention leaving a mess behind. They're awfully small, and now thinner...
  8. Waiting, or rather being forced to wait, for night-fall... This time round I'll be sawing outdoors, upon the saw-horses, as the sawing of this brass rod produces a lot of "chaff".
  9. Often, the reason for selling a telescope of that size is due to its being rather large in the first place; a case of biting off more than one might chew. It may, perhaps, have seen very little use, if any at all. Their loss is your gain, so go for it. But be forewarned: its parabola will hunger for corrected and therefore costly eyepieces.
  10. I may just imagine two stacks, of spherical and parabolic mirrors, on a table, there at the factory. An assistant is told to go and fetch a mirror from one of the two piles. However, the assistant is blindfolded. If the primary-mirror is without a centre-spot, then I would strongly suggest that one be placed... https://garyseronik.com/centre-dotting-your-scopes-primary-mirror/ Use a white, plastic reinforcement, instead of a paper one, and for durability.
  11. You can begin with a 2x-barlow, as they're more commonplace. A 3x-barlow is useful, too, but you'll want the collimation spot-on when using that one, and for the highest powers. A telescope has to work harder as you go up in power, therefore a precise, or nigh enough, collimation becomes paramount. It would be reasonable to expect 150x or so in the beginning. Your telescope has a focal-length of 650mm. That's what you use to determine your selection of eyepieces... 650mm ÷ 150x = a 4.3mm eyepiece, but let's round that off to 4mm(163x). You can see the planets quite well at that power, particularly Jupiter and Saturn. Then, again, in that the Moon is so very near to the Earth, you can use considerably higher powers to observe its details, up to 250x, and beyond perhaps. You can combine a 9mm(72x) eyepiece with a 2x-barlow for a simulated 4.5mm(144x); then, a 12mm(54x) eyepiece, for a simulated 6mm(108x). This is my 12mm eyepiece inserted into a 3x-barlow, and for a simulated 4mm... I have the benefit of a larger eye-lens through which to observe, whilst retaining the greater eye-relief of the 12mm by itself. I also have this 4mm eyepiece... Note how it appears quite similar to the eyepiece-and-barlow combination above. That 4mm eyepiece contains a built-in barlow, and for a single, tighter unit. To help in finding objects in the night sky, to aid the finder in same, a 32mm Plossl is suggested. The 32mm would provide the lowest power and the widest view of the night sky; for hunting and spotting, then to increase the power for a closer look. It may also be used to observe the largest objects in the night sky: the galaxy in Andromeda, and the Pleiades, in winter. In summer, the star-studded fields of the Milky Way unfold. Going from a 32mm to shorter, I prefer a 20mm over a 25mm; then, a 12mm or 16mm. I think that a 12mm is more versatile, as you can reach the higher powers when combining it with a 2x or 3x barlow, more easily. If we knew where you're located here on Earth, we could help you to find online listings of these items, and go from there.
  12. Respectfully, I have the same, what I term, "one arm bandit", and as the Bresser "Messier" 150/750 Newtonian-Dobson... ...but under another marque and colour-scheme. As you can see, I transferred the OTA over to a tripod-type alt-azimuth, and it has been far more enjoyable. I then chucked its dreadful, one-arm Dobson base up into the attic, and where it will rot. It shall never be missed. If a Newtonian-Dobson, choose one(at 150mm and up) where both sides of the telescope are supported; for example... https://www.astroshop.eu/telescopes/skywatcher-dobson-telescope-n-150-1200-skyliner-classic-dob/p,15559
  13. I made a mistake... The brass "buttons" are too thick, perhaps even the original black-plastic ones, as the brass ones are only slightly thicker. There are built-in stops on the head for the two black clamping-levers. The levers still did not go past the stops, but just barely. I'm going to make two more, and this time at 4mm in thickness, 1mm thinner than the originals. I was able to rattle out the brass "button" for the RA-axis, but the DEC proved more difficult, and how. In the end, I used five-minute epoxy, and attached a toothpick to it... Incidentally, when duplicating a metal part, not necessarily for this mount, and with plastic or wood, the part generally has to be made larger or thicker to maintain the strength of the original part; wooden spoons are larger and thicker than metal ones, for example. This, however, does not apply to all man-made, metal articles and instruments. But in this case, I did it in reverse.
  14. I have this one, and purchased about twenty years ago... https://www.grizzly.com/products/grizzly-7-x-12-mini-metal-lathe/g8688 ...but it's fouled at present, rust mostly, and will need a nigh-complete restoration, if such is possible at this point. I'm not aware of having once been a watchmaker. I do directly descend from Benjamin Franklin's eldest brother, if that helps.
  15. Now, that's the way it should be, nice and smooth. It's a shame however that I did all of that for a piece of useless fluff, but we'll see if I have to eat crow some day. Incidentally, I found the other on the floor. It turns out that there were originally two of these embedded within the glue-grease on the underside of the setting-circle... ...and for a total thickness of 0.026"/0.65mm. But why wasn't one on top of the circle and one underneath; why both underneath? Do I really have to ask? In any event, the two bronze washers that replaced them are a total of 0.016"/0.41mm, but then I did add the thicker bronze washers along with the needle-thrust bearing under the DEC lock-nut, so it balanced out I suppose.
  16. Thank you ever so much, Robert. I appreciate your faith and trust in my abilities, but I would not need to produce an equatorial in the first place, as I have this one, and for a lifetime. In addition, do you realise what I would need? For one, a $50,000 gift-certificate from this online-vendor... https://www.grizzly.com/ ...not that I'd really need that much. However, it's not likely that they'd give me one for free, just for being a good fellow. Then, there's the metal stock to consider. Indeed, you can convert most any equatorial into an alt-azimuth, including the one I'm detailing. You simply extend this part outward... Then, there's this... https://www.firstlightoptics.com/skywatcher-mounts/skywatcher-az-eq6-mount.html ...and proof of the Janus-complex that exists between the two types.
  17. The washers have been sawn out, and dressed to fit... Now to polish the inner-diameters before cutting them out from the sheet.
  18. I was thinking that I was done with making these bronze washers. It's gruelling work, but I certainly didn't mind doing so for the axes, as I was on a mission, and one accomplished; but for these setting-circles, really? The washers are ready to have their inner-diameters sawn out... Perhaps they'll take the sting out of actually using them to try to find something.
  19. This 0.008"/0.203mm thick bronze snippet from the sheet has its Xs... Those will be the two washers, the smaller at 28mm x 35mm, the larger at 26mm x 40mm, for the DEC setting-circle assembly.
  20. If a centre-spot is absent, that's generally indicative that the primary-mirror is spherical rather than parabolic. I have three that arrived like that, however one was parabolic. But all 130mm instruments, at f/5, must have a parabolic primary-mirror to perform at their best. It is to be expected, rather than hoped for, absolutely. In the past, and perhaps still, Synta has been chucking spherical primaries into their Celestron "AstroMaster" 130mm f/5 Newtonians... https://www.celestron.com/blogs/knowledgebase/does-my-astromaster-130-have-a-spherical-or-parabolic-mirror-what-is-the-difference ...that in 2011. On the other hand, a 130mm f/7 has a spherical, yet diffraction-limited(1/4 wave being the minimum, but that one is at 1/5 or so), and therefore performs quite well.
  21. Ah, I see. That's the same type of motor-drive kit that I had been looking at, but for the RA-axis only. Now, at present, the worm of the RA-axis rotates ever so freely and smoothly. I don't know if that will change, hopefully not by much, once a load is placed.
  22. Not at all, for I love to answer questions, or to at least elaborate upon them further. The wee motor-drive has a speed-control, a varistor, which will compensate for any discrepancies... Would that all motor-drives had a speed-control. I'm a bit leery about acquiring a drive with a hand-controller, unless there's some way, somehow, to add same. Hmm, you mentioned that your clutches loosened. I have to wonder if I've eliminated that possibility with the brass clamp "buttons". In addition, they are somewhat larger, and will not compress. Time will tell. I may even have to tighten up the axes, albeit slightly; the RA-axis in particular, for as I was rotating the axis with the worm, with the head on the tripod, I detected a bit of shuddering. Of course, there was no telescope, or counter-weight, attached.
  23. Indeed, and with this... https://www.firstlightoptics.com/celestron-astromaster-series/motor-drive-celestron-astromaster-geq-93514.html I got it for my EQ-1 and EQ-2, but it looks like its very first use will be with this Synta EQ-5(Meade LX70). Incidentally, it has been done before, and successfully. I will need to be creative in its attachment however, and possibly with wood. Do you have mounts that are motorised? The last time I used a motorised mount was back in the early 1990s, and with this Parks Optical EQ-2(made in Japan)... I watched Venus from about 5:30 in the morning whilst it was still dark, and until almost noon. It was wonderful, and I'm wanting to experience that again.
  24. <gasp> The DEC-axis is upside-down... Juuust look at it... That's one sorry assembly, the DEC setting-circle. It's reputedly ineffective, and its execution is deplorable. The clear washer there is 0.0125"/0.32mm in thickness, and fits underneath the setting-circle, and on top of the DEC lock-nut. That's the only location within the entire mount-head where I found factory glue-grease. The RA setting-circle, no doubt, is saturated with it, too. The glue-grease is used, wait for it, to compensate for hastily and poorly designed assemblies. In that I might actually try to make use of it, it will need, not one, but two washers of the thinner bronze, one on each side of the circle.
  25. Aren't they lovely? The clamp-bolts were dirty. The one on the right is still fouled with the factory-grease... Whilst clamped, the axes are immovable, even when pressure is applied; success. However, I am mindful that I've yet to put the mount-head into practice, and with one of my heaviest telescopes attached... Time will tell.
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