Alan64

It may be worth noting, also, that the bronze washers I made for the secondary ball-bearing assembly had to fit, drop into, this depression... I arrived at two 0.008"-thick shims for the secondary ball-bearing assembly by subtracting the widest diameter of the RA-shaft(34.76mm) from the inner-diameter of the ball-bearing assembly(35.6mm) = 0.84mm. I then divided that by four, and for .21mm(0.0082677165"), but at the time I came up with twice that, somehow, some way... http://gph.is/2iPNjr1 Yep, that must've been how. *EDIT: No, wait a second, I divided that result by two, which is correct. I suppose both will fit, but it would be too tight, I suspect.

The slathering continued... Only one shim would fit, and that will do. You want to screw the RA lock-nut onto the shaft until you come to a dead-stop. Then, back the nut off one-quarter of a turn, and tighten the nut's three set-screws. *NOTE: Be certain not to mistake the dead-stop caused by the initial, factory set-screw indentations into the aluminum threads, and for the actual dead-stop either a tad farther, or a tad behind, whichever. O! My stars! The motion is though it were temporarily greased with the smoothest butter imaginable, and with no slop whatsoever. I could not be more pleased. There it is, peeking through those holes: the secondary RA-washer, and perched atop that narrowest of ledges! Synta!

The time had come, and upon awakening from my slumber... All surfaces that touch one another were, shall I say, conservatively slathered with the Super Lube grease. This also includes the full outside length of the RA-shaft, and the outside of the RA worm-gear. Now, if the latter proves a problem, when clamping the axis, I can remove the grease.

You flatter me, sir. But I think that you can do this yourself. That's why I'm detailing everything.

A Maksutov is the closest that a reflector, utilising mirrors to form the images, may come to simulating the performance of a fine refractor, including the reduced need to collimate. But when a Maksutov does require collimating, it can be the most daunting among all reflectors. Then, you have a Maksutov's rather long focal-length, and the longest among all reflectors. When paired with a manual mount, a larger optical-finder is most helpful, or a red-dot in a pinch. My own 127/1900 Maksutov makes for an effective simulation of this 112mm f/18 achromat... ...yet within a short, compact tube... Indeed, Maksutovs are used during the day, and for long-distance spotting. At night, a Maksutov is like a microscope, but for the sky.

For upright, corrected images during the day with a refractor, an Amici-diagonal is used; for example... https://agenaastro.com/baader-1-25-90-amici-prism-diagonal-amici-45-2956150.html

A triplet-refractor is generally chosen for astrophotographic pursuits, with a camera and a go-to equatorial mount. Triplets are also more delicate, more prone to mis-collimation over doublets, and are not usually user-serviceable if service is needed. Triplets also tend to be front-heavy. I'd take another look, a hard look, at that 76mm fluorite-doublet. My Takahashi FS-102, from 2003, has been described as "mythical"...

https://www.landseaskyco.com/takahashi-takahashi-fc-76ds-refractor-telescope.html

Excellent questions, those, and as it turned out, prior to reading your post, I had already decided to forego the marine-grease. Super Lube is definitely super, superior.

Just now, I took a small dab of the Lucas marine-grease, and rubbed it between my thumb and forefinger. I then did the same with the Super Lube. I did both twice. As a result of this "taste" test, I will be greasing this mount-head with Super Lube, rather. I can use the other for more common tasks, and unrelated to astronomy. Why, Super Lube is waterproof itself.

The shims for the secondary ball-bearing assembly are completed... Both shims within the ball-bearing assembly... The shims are not only to take up any slop, but just as importantly, perhaps even more so, to isolate the steel inner rim of the assembly from the threaded aluminum of the RA-shaft. I may not be able to insert both shims in the end, but we'll see, as one will do just as good a job as two. Bronze is truly beautiful, when it's not tarnished...

I had gone out to one of my local big-box hardware/lumber stores yesterday afternoon, and got a tube of Lucas Marine grease. I've had the Super Lube for a few years... ...the one white, the other a greenish blue. Jeff DeTray, aka "Astronomy Boy"... http://www.astronomyboy.com/ ...is something of a pioneer in refurbishing the earliest of these larger, Chinese-cloned, equatorial mounts, the first-generation CG-5 in particular(I believe Helios-branded in Europe). Mr. DeTray found rough areas within his CG-5 mount-head(s), but I did not within this Meade LX70, not in the slightest. Mr. DeTray also returned the plastic washers to the mount-head, whereas I will not. In addition, the gentleman stated that he has had no personal experience with the second-generation CG-5, manual still, but with ball-bearings, and most likely identical to the Meade LX-70. Robert Burns, mentioned within DeTray's site, who refurbished his second-generation CG-5(or the third, a CG5-GT, that is, the go-to variant) used Quaker State marine-grease to re-grease his mount-head, however that particular marine-grease has been discontinued, and for quite some time. But lo and behold, I did find three tubes of the stuff this morning... https://i.imgur.com/igMKXb0.jpg No, I won't be getting a tube, but it was the use of such that sparked my interest in marine-greases. These marine-greases are perhaps primarily for water-craft and such, hence "marine". Such are large, and containing large-scale parts. By comparison, these mount-heads contain relatively small parts, for relatively smaller loads, and perhaps in no need of such a heavy-duty grease. However, I will be using the new marine-grease for this mount-head, and for these two reasons... I live in a humid, sub-tropical climate. I'm not thoroughly convinced that Super Lube is head and shoulders above the rest. All that's left to finish before reassembling the RA-axis are the shims for the secondary ball-bearing assembly.

Hi, At night, the grass, the ground, can become quite wet with dew, as does the telescopic equipment. In addition, it may be desirable to observe after an afternoon storm, the ground wet still as night falls and progresses, as the storm had scrubbed and washed all of the particulates out of the sky. But whilst the transparency is very good after such, the seeing is generally poor. I'm afraid we can't have our cake and eat it too in that. Self-adhesive Velcro would be ideal to attach the adaptor to the tripod/mount, the higher the better. Also, if you don't have one already, a dew-shield for the front of the telescope will help to keep the front "lens" of the telescope clean and dry, also to prevent stray lights from reaching same. I have one for my catadioptric... I didn't even take that one out for the very first time until I had it protected.

Hello, and from the 20th colony. In that it is summer, especially, you'll want to protect the front of your telescope, the corrector-plate or -lens, and with a dew-shield. For example, I got one for my catadioptric... It will help to keep bugs, dirt, dust, moisture and pollen away from and off of the glass. It will also help to prevent stray-light sources, natural(the Moon) and artificial(light from the street, houses, automobiles) from reaching same. Be certain to get one that's lined with an absorptive material, and enjoy.

I love pie...er, π, pi... 35.6mm x 3.14(ad infinitum) = 111.84mm How about an even 111mm... They will actually be somewhat shorter when finished, and the ends blunted, rounded.

The birth of the two shims for the inner-diameter of the secondary ball-bearing assembly... Why, they're twins!

I have already made merry mention of galvanic corrosion, and when mixing aluminum with other metals. Although, that should not be a problem if the metals are thoroughly greased, but never to excess. You don't want globs of grease within your mount-head, again, like when it left the factory. Then, the manufacturers do combine brass worms with aluminum gears, so it can't be the monster I've suspected; or can it be? There is another caution that presents itself. The plastic washers would perhaps or definitely never wear down and away the aluminum surfaces with which they come into contact. Plastic would seem to be softer than aluminum, at first thought at least. But what about bronze, bearing, rubbing, against said surfaces? If indeed a problem, I would be wary of using bronze within a go-to equatorial, with its motorised slewing-speeds, over the months and years. Copper, and brass even, are softer than bronze, and therefore less destructive. As for myself, my enhanced mount-head will motion ever so slowly, even when simply motorised with a small drive, like the pendulum of a clock, or a tortoise even. Got a CG-4, or an EQ-3? Here's what's inside of it: plastic and red fibre washers... Get those out of there, if you might, and add ball and/or needle-thrust bearings even.

https://www.youtube.com/watch?v=b9xDvX2_v0k The secondary RA-washer... There it sits, and perched atop its ridiculously narrow ledge all round. Meh. Ah, but this, this, the primary RA-washer, and which happens to be the narrowest of the four washers... Glamour shot... All of the gear's teeth are visible from overhead, which is why it's narrower than the secondary washer... You don't want the washer interfering with the worm as it meshes with the gear. This, yea, this, is what makes the Earth stand still...

I broke several of my jeweller's blades getting these cut out. The sawing is done, but I've yet to snip the larger washers out from the sheet. It turned out that the thickness of the ball-bearing's original enclosures, surrounds, whatever, are also 0.020".

For the RA-axis, the circles for four washers have been described onto the 0.020" sheet of phosphor-bronze. Note, there on the right at the bottom, where the compass leg went astray, but no matter as that lies within the scrap area... Yes, four washers, two for the RA worm-gear, and two for the secondary ball-bearing assembly... The dimensions of the ball-bearing washers were arrived at via these measurements... Those parts are actually sloppily-fitting. As a result, I will be making a shim from two 6mm-wide strips of 0.008"-thick phosphor-bronze... The inner-diameter of the innermost washer is 1mm larger than the outermost, and per the RA-shaft... ...34mm and 35mm, roughly. The red line illustrates the division between the inner and outer portions of the shaft. Once the four washers are cut out, dressed and polished, the RA-axis can be re-assembled. I used Super Lube grease for the latitude-axis, but I'm wondering if I should use marine grease for the rest of the mount-head. I haven't decided yet.

Yes, Snap-On tools are stellar as well, although I've never owned one.

The relation saw what I was doing, whilst using the China-made, and introduced me to those. What a wonderful introduction.

Starting over from scratch, the following measurements for the RA-axis's washers were made with a relation's Mitutoyo digital-calipers, and leagues above my generic Chinese calipers... The RA primary washer... The RA secondary washer... I suppose that the inner-diameters of both can be made at an even 62mm; but no narrower than 61.80mm for the primary. However, that for the secondary washer is most critical, given the rather narrow bearing surface onto which it will rest... Then, the inner-diameter, at 61.95mm, is quite close to 62mm after all, but we do want that as snug-fitting as possible. Why, you could even glue the washer into place if you wanted. In so far as the outer-diameter, it can be the same as the bearing-surface itself, but I'd hate having to make a washer that narrow. The washers will be born from this beautiful 152mm x 90mm x 0.020" sheet of phosphor-bronze...

The time came to unfurl the roll of bronze sheet. I began by cutting at its cardboard band within the house, but then decided to take it out to the shed. Good thing that, as it violently exploded to its full length once the band gave way...

I neglected to mention: since the thinner washers did not fit initially, I then decided to level the other hub with its spokes, thereby reducing the need to sand the washers further... The total thickness of the washers per side is roughly 0.0575". In future, I may re-do this with one washer per side, and of brass. Incidentally, aluminum doesn't play well with copper, brass, or bronze, among others... https://www.archtoolbox.com/materials-systems/metals/galvanicaction.html However, it seems that if the dissimilar metals are saturated with grease, then there shouldn't be a problem. Food for thought, and when incorporating said metals within this aluminum mount-head.