Part One: Maintaining and Adjusting the "Stock" Orion Bearings

The standard Dobsonian telescope alt-az mount is a good, simple, workhorse device, but it was scarcely "invented" by telescope maker John Dobson. It is merely an adaptation of the way large reflector telescopes were mounted by William Herschel. In the 1780s, Herschel employed gargantuan metal alloy mirrors (made of what was called "speculum") to discover many deep-sky objects that could not be seen in the small refractor telescopes of his contemporaries. Once, I went over Herschel's papers and took his calculations for the reflectivity of his 17.8 inch "speculum", and determined that if his findings were correct, his most-used survey telescope would perform about as well as a modern 15" aperture Dob -- except that Herschel did not benefit from today's low-loss, wide-field oculars; he typically used one small hand-polished lens, getting a very narrow field of view, allowing objects to drift through his eyepiece field. Then, he'd drag the big old telescope around a bit, and start all over again...

John Dobson's mount, having the same movement in altitude and azimuth as Herschel's, was lighter and more efficient, because the MIRROR was no longer a heavy metal monster weighing hundreds of pounds. Dobson also was able to experiment with modern plastics and metals that were not available to Herschel. My own first attempt to make a Dobsonian telescope came many years after I had acquired "pipe mount" equatorials. After some trial and error, I built an 8" Dob, in the late 1980s, that served me quite well for an entire decade. To improve the smoothness of the "action", I eventually obtained the standard recommended parts for the bearings: pads made of DuPont's Teflon®, and a large sheet of Ebony Star 4552-90 Premium Laminate, made by Wilsonart®. These two products, working together in the Dobsonian telescope bearing system, appear to give the smoothest possible motion with a minimum of "stiction". And, the standard advice of most ATM's was to improve the action even further by applying a VERY light coating of ArmorAll® protectant. I did that, and got good results, with very smooth telescope motion.

When I first purchased my Orion SkyQuest 10" Dob in the late summer of 2005, I had to chuckle at the wording of its instruction manual, which described the action of the Dobsonian mount as "buttery smooth". Nothing seemed to me to be further from the actual truth of this assertion: the action of the telescope was far stiffer and more sticky than my old home-made Dob mount, with Teflon and Ebony Star. I suppose that the Chinese factory that made the Orion scope put their attention in the right place, for -- after all -- the mirrors in this scope are WONDERFUL and far exceeded my expectations (indeed, user after user makes similar comments about these Orion Dobs, all over the Net.) But the mount -- whew! It was a struggle to use at first, especially in the altitude motion. I finally decided that enough was enough: I had to modify it.

Unlike my own old home-made mount, which operated on a very fine balance achieved by moving the tube assembly inside a cradle that fitted around it, the Orion scope's metal tube is permanently affixed to the altitude bearings. To make sure that the scope works with a variety of eyepiece weights, and with different finders, a heavy spring pulls the altitude bearing down into very firm contact with two extremely thin, slightly curved white plastic pads (seen here) that are stapled to the inside curvature of the press-board mount's vertical sides. I very seriously doubt that these pads are made of Teflon; nor do I think the apparently identical (but larger) ones on the azimuth bearing are the superior DuPont material. To improve the altitude motion I needed to release some of that tension, which I did by adding three different fasteners on each side (made merely of long bolts, nuts, and washers), spaced about 3/4 inch apart below the bearing, the highest one barely putting any tension on the spring (for use when the scope was pointed nearly at the zenith, where little bearing pressure is required.) Now, with less downward pressure it was much easier to move the scope tube up and down; and luckily the balance was still correct with all my eyepieces, and even with an additional Telrad finder, though I now may "fine tune" the pressure if necessary when the scope is pointed near the horizon.

But, I suffered with the azimuth motion, which was exceptionally stiff: and over the months, stretching past a year, it got stiffer yet. Finally it seemed to be an absolute CHORE to point the telescope, and I took a look at the instruction manual to see if there were any suggestions about maintenance. But, aside from very thorough and correct information about cleaning the mirrors, nothing at all was said about the mount or the bearings. I was on my own. As I used to be the Product Development Coordinator of Orion Telescopes, as well as an amateur telescope maker myself, it simply did not occur to me to call them about this; would their telephone service people have thirty years' experience out under the stars? I was doubtful about that. But, I did check with similar scopes on the showroom floor of their Cupertino store, and found most of them to be almost as stiff and unyielding as mine...

Just as spring was dawning in 2007 I got a yearning to work less hard while using my SkyQuest -- which otherwise is a marvelous and very productive instrument -- and decided that the azimuth bearing needed attention, too. So as usual, I looked on the Net to see if others had coped with the problem.

I found nothing specific about the Orion SkyQuest mount, but there were countless webpages and forums and newsgroup posts about using ArmorAll! Just the same advice that I followed years ago, with nary a single objector. One or two people seemed to prefer something called "Pedro's Ice Wax All Purpose Bicycle Chain Lube" (which you'll find buried in the website of Pedro's Bicycle Products if you're persistent enough) but ArmorAll seemed to carry the day, as I found hundreds of very positive references, in discussing Dob mounts, that had no indication that there could be a downside to its use.

I went into the garage on the afternoon of 8 April 2007, just before loading my Orion Dob and all other astronomy goodies for a mountaintop observing session, and found my bottle of ArmorAll (which is regularly used to keep my wife's car looking spiffy); and gently applied a bit of it to the white pads. I wiped off any dribble and smiled, considering this a "problem solved", expecting to enjoy myself with trouble-free viewing. For good measure, I also cleaned thoroughly the press-board base of the mount: the bottom of the rocker box. It had picked up streaky bits of white plastic that had sloughed off of the pads.

But, what I found two hours later, when I finally got my first eyepiece in the focuser of my Dob, was a horrible situation. The mount was RUINED! The action was now coarse, sticky: it shuddered. I could barely move it except in the most rough manner. Applying pressure in my normal way, I found that at first nothing would happen, with no motion whatsoever; then at a critical pressure the mount jumped and would lurch, taking the object I had in the eyepiece way out of the field. I tried to watch Saturn at 100x and saw that the seeing was incredibly good; pumping up the magnification to 200x, I simply could NOT get the planet in my eyepiece: I kept "jumping past it" as I tried to point the scope. I tried Herschel's trick of moving the scope ahead of the sky, waiting for the object to drift into view. But, try as I might, I could not do this reliably, now, at 100x, or even -- to my shock and dismay -- at 40x! The telescope motion was WRECKED.

I realized at once what the problem was: STICTION. Believe it or not, there's a Wikipedia page for it: and pretty well written, too, so I needn't elaborate. The problem was equivalently obnoxious in both altitude and azimuth: and the common factor was the application of ArmorAll to the bearings.

After a good forty-five minutes of struggling, I finally decided that I could go no further; took the scope off the mount and gently laid it in its carrying case; and got out some alcohol cleaning wipes that I keep in the car, and did my best to remove the ArmorAll. I could not reach the azimuth bearings without disassembling the base, but I did my best by trying to insert the wipes between the pads and the base; finally I used sheets of clean typing paper, and rubbed and rubbed, hoping to take all trace of the residue off the surfaces. I replaced the scope; but though the motion was smoother, there was still quite a bit of irritating stiction, particularly on the azimuth bearing, which I had not cleaned as effectively. I gave up, cut short the observing session, and went home: dejected and furious.

The next day I disassembled the mount and cleaned off the base very carefully (with a very gentle solvent called "The Green Solution" by Pro Power, seen here on the website of Blue Cross Laboratories, the maker.) I had learned of this cleaner from advice given on the antique radio collectors' newsgroup: it is non-damaging to plastics and does an excellent job of removing gunk without harming anything. Local "dollar stores" in the San Jose area carry it -- for a dollar!

I also used a bit of acetone on a cloth to wipe off the white pads on the base, and in the altitude bearing. But I discovered by testing the edge of the round black plastic bearing on the scope tube that ACETONE WOULD EAT IT and damage the surface! So I cleaned those two plastic bearings ONLY with the "Green Solution" cleaner.

In fact, always exercise extreme caution when using acetone with most materials. It will damage many things, though it's an exceptionally good cleaning solvent.

I allowed a half hour of drying time, and then went over all the surfaces again with a lint-free clean and dry cloth. There was not a trace of any extraneous substance on the pads or the base or the bearing. Everything was also as dry as a bone, with NO lubricant residue whatsoever: the way the scope was ORIGINALLY made.

There was still a slight amount of stiction when rotating the azimuth bearing. Examining the three small white plastic bearing pads, I noticed that they were each attached to the base plate with a long narrow staple, which caused a slight puckering of the plastic. I carefully pried the pads loose with a thin blade screwdriver and examined each plastic square. One side looked more worn than the other, in each case. Obviously over a year's use, the plastic had become somewhat scuffed by friction with the rocker box: this accounted for the streaks of white plastic that had worn off. I polished each side of the bearing pieces carefully with a cloth and Green Solution. Then I held each one up to the rocker box bottom by two fingers, and moved it around. I could tell that one side of each piece moved VERY smoothly, while the other side moved more stiffly. I marked the stiff side "B" (for bad) and then took my Dremel tool, and -- using a very blunt round bit -- created a little depression right in the center, a fraction of a millimeter deep, around one of the holes left by the staple. I took a small carpet tack, which fit into the depression, and drove it through the hole, making sure that the head was in the depression, well below the top of the plastic pad. Then I tacked the bad side of the bearing piece down onto the bottom board, with the good side "up" toward the rocker box. (Perhaps the preferable way is to attach with permanent cement but I wanted to test this arrangement first. Later, when I am entirely satisfied with what I've done, I'll remove the tacks and glue the pad down permanently -- and get a spare set of real Teflon pads for future replacement use!)

The rocker box rotated more smoothly, without the scope; but with the added pressure of the optical tube, it became somewhat stiff again.

I decided before giving up and accepting the improvement I had made, to take one more look at the Net and see if I could find any useful suggestions, and if anyone had ever posted a warning about using ArmorAll with this type of scope. I found no caveats about using any particular solvent or lubricant with the Orion Dob base and bearings; but I did locate an interesting page that recommended using a compact disk as an extra central azimuth bearing in a discussion on an ASTRONOMY magazine ATM forum. I confirmed this with several other discussions and articles about improving Dob bearings, suggesting that one cut out and fashion large extra washers from the plastic material used in milk jugs -- or use an old CD. I found that on one of the two surfaces of the press board azimuth bearing in my mount there was a shoulder washer, which stuck out a bit but did not touch the other board. I placed one old compact disk on the center of the bolt holding the boards together which, in my mount, was all that was required to add just a LITTLE more support to the center post, barely touching the other board when the telescope tube's weight pressed down.

I reassembled the mount, placed the scope on it, and took a deep breath:

SMOOTH AS BUTTER!

Inserting a Barlow and my highest power eyepiece, I looked at trees down the street and shingles of my neighbors' houses, at more than 400x. I could move the scope now with the SLIGHTEST and most gentle pressure; it started to turn at once without ANY jerking or jumping, and then stopped immediately. It was, in fact, MUCH better than it had been when brand-new.

This was achieved, I must emphasize, WITH NO LUBRICANT WHATSOEVER! NO trace of ArmorAll, or anythingthing else: just clean, dry surface-to-surface contact of the bearing material.

With the improved fine adjustment of the altitude bearing pressure -- using the spring under the lowest-tension support -- I could now point the scope up toward the zenith and make VERY fine movements in altitude, even while using a magnification of 400x, without the slightest bit of jumping, jitter, or sticking. Similarly, with the improved freedom of the azimuth bearing, the scope no longer shuddered or even creaked (as it used to do), now allowing me to track the motion of Saturn easily, while it was high overhead in the constellation of Leo. All in all: an astounding improvement, with motional smoothness now comparable to my old homemade Dob.

I have no doubt that using ArmorAll is VERY effective with the "standard" ATM combo of Teflon/Ebony Star; I've done it myself. But: it does not work with the materials in the Orion SkyQuest Dob mount. The surface is different in some distinctive, important way; lubes don't help but actually make the problem worse.

Now, the important thing that I must urge my readers to be aware of is this:

DO NOT BLINDLY TAKE ADVICE YOU GET ON THE INTERNET!

Do not, in fact, automatically accept anything I have said, above, in this article... don't merely go to your telescope and do ANYTHING at all that I have described, without very thoroughly considering your options. Check everything out with other persons' testimonies. Be certain that the advice they give works IN CONTEXT with what YOU are going to do. The problem with the standard advice given to Dob owners who want to improve the actions of their bearings is, in my case, that the context was wrong: the advisers were not using the same bearing material that I had in MY scope.

And, who knows: maybe Orion's bearing material CHANGES over time, and your scope -- even if it seems also to be a SkyQuest Dob -- will be significantly different in some respect than mine is. You never can tell... the details of products do change all the time; retailers even change suppliers, though the new factory uses the same blueprint employed by the prior maker. The product might look identical, but be very different "inside".

Now, I have every respect for ArmorAll and consider it a very fine product; of course, the company has never marketed it as "a telescope accessory". But, I'd use it on A DIFFERENT DOB, after doing some tests to make sure it was satisfactory. And, I'd test it AT HOME, at my leisure, not merely apply it just before leaving for an observing session.

Part Two: Replacing the Original Pressure Bearing with Ball Bearing System

After using the scope for two nights with the repairs described above, I was reasonably pleased with the improved performance. But I found that the white plastic in the Orion azimuth pressure bearing material was still rubbing off onto the rocker box bottom. After several hours' use, the rocker was once again scored and scuffed with streaks of this white plastic material (whatever it is), and the more that accumulated, the less smooth the azimuth rotation was becoming. You'd clean it off; then after the scope had been revolved a while, it would build up again. This is why I suspect that the square white plastic pads are not the authentic Teflon material that I had used in my own home-made Dobsonian mount. I only noticed this slight deterioration in smoothness AFTER having improved the azimuth bearing performance of the scope. It wasn't as smooth 'in the field' after two nights' use as the rotation had been in my garage workshop.

I was aware of the use of a "lazy susan" type steel ball-bearing system in some commercial Dobsonian mounts, such as the Meade "Lightbridge" scopes, which have steel roller bearings instead of the pressure system of 'standard' Dob mounts. The use of a roller bearing system requires a tension adjustment in order to prevent the scope from moving too freely, allowing wind, or even the slightest touch while operating the focuser, to cause the scope to move off position. I reckoned that I could use the same technique that I had employed on my old home-made mount, using a spring and tensioner nut on the central azimuth bearing shaft's bolt. This turned out to be a very fussy and time-consuming process, but eventually I was able to cobble together the right assortment of components to get the tension I desired, as explained below.

My local hardware stores had no lazy susan bearings larger than 4" in diameter, way too small to support the mass of the scope. I quickly found online an appropriate 12" bearing, quite adequate for my 10" scope tube assembly, from the Rockler Company: see this page of their online catalogue. I had purchased esoteric furniture hinges from Rockler before, and knew they delivered great service at prices that were generally lower than local retailers (that is, WOULD be lower, had the stores carried the products at all!) Rather than spend days searching around for a furniture repairer who had such a bearing in stock, I placed a mail-order and received the 12" bearing (Rockler part no. 28985) in about 8 days (though the cost of shipping was more than the bearing itself.)

I decided to make the modification to the rocker and base as non-destructive as possible. That way, I could always go back to the original pressure system if the ball bearing assembly proved unsatisfactory. The main concern was positioning the bearing so that it was perfectly concentric with the central shaft hole. To do this, I used a caliper and made many pencil marks on the rocker base, moving the bearing by tiny fractions of a millimeter at a time until it was EXACTLY centered with respect to the central hole. (I must have done a perfect job, for the end result was completely smooth rotation of the rocker with no "planetary offset" and no erratic tension on the central bolt.)

Normally when this type of bearing is used on a rotating chair, each side is bolted in place firmly. There are holes provided to allow one to insert and tighten screws from each side. I reasoned, however, that it would be necessary ONLY to attach the bearing plate to one part of the assembly, not both: so I drilled four properly-marked holes through the base of the rocker board, and screwed down the bearing from that side only. I removed the square white plastic pressure bearings and reassembled the mount. As expected, the azimuth rotation was far too "free": the slightest touch would cause the scope to roll. I attempted to increase the tension by putting a spring between the base of the rocker board and the central shaft locking nut, with washers at each end. But, even with the nut cranked down tight, compressing the spring, there was insufficient tension. And, I did not want to warp permanently the ball bearing assembly.

So I experimented with the three original pressure pads, putting some rubber under them to get the pads elevated slightly in order to touch the bottom of the rocker box. No matter what I did, the result was never QUITE right. The azimuth system now had either too little or too much tension. I then took off the white pressure pads completely, and substituted two layers of rubber-backed carpet runner, cut into little 1-1/2 inch squares. The carpet-side was arranged to scrape lightly onto the bottom of the rocker box, just barely touching it when the scope tube was in place on the cradle (which does add a little pressure and warpage to the wooden structure.) After about 30 minutes of adjustment and testing, I had the height of the carpet pads optimized, and by finely-tuning the locknut pressing onto the central spring (as shown below), I had a small range of tension control.

Now, the scope would rotate in azimuth with a very slight application of force, though far less than with the original pressure bearing system. Removing the force would cause the tube to stop instantly, with no trace of bounce or backlash. I could put a high magnification ocular in the scope, even with a Barlow, and make very fine positioning adjustments, tracking the celestial motion with little difficulty (now that I had made the provision for adjustment of the altitude tension, described earlier.)

I also made a simple addition to the base in order to provide more mass and reduce the tendency of the rocker box to "tip": adding three round iron barbell weights (2.5 lb. apiece) that I purchased at "Big 5" Sporting Goods for $1/pound. I drilled two holes in each weight and screwed them to the bottom of the bearing board, against the three rubber feet. The addition of weight made the assembly more solid without increasing the mass on the rotating rocker itself.

I considered this modification a complete success, and certainly worth the cost of $16 for the bearing and shipping, and the several hours' work that preceded and followed its installation.

Part Three: Balancing the Tube Assembly

There was ONE imperfection remaining, from the original design of the telescope tube assembly and mount. The central pivot of the tube assembly was mounted not at the point of perfect balance, but closer to the opening azimuth end than ideal. Normally this would cause the scope to be top-heavy. But by applying a large downward tension onto the altitude bearing, by means of two hefty springs, the tube assembly would TEND to come to rest quickly, no matter what eyepiece was used. There was so much tension in the altitude bearing, however, that I found it very difficult to point the scope near to the zenith. Thus, I had added three extra bolts on each side, in order to permit "fine tuning" of the spring tension. With the scope pointed down near to the horizon, heavier tension was necessary than with it pointed nearly straight up. This was a workable but slightly fussy arrangement.

My old home-made 8" aperture Dobsonian design used a sliding pivot box to hold the tube assembly, with altitude bearings that were about twice the diameter of the ones in the Orion mount for the 10" aperture tube assembly. In addition, I surfaced the bearings with a narrow, curving strip of Ebony-star, and used 'real' Teflon blocks. There was perfect static balance in my old design, as I could fine-adjust the position of the tube assembly in the pivot box. Orion's design makes no provision for this. You get what you get; the system relies on the spring tension to try to eliminate 'tippyness'.

But this is only an approximate solution. The altitude tension required to move the scope up and down varies continuously, depending on the pointing angle of the tube assembly. Even my coarse-adjuster bolts could not eliminate that problem. Furthermore, the focuser and finderscope were positioned on one side of the tube assembly, which places a little bit more pressure on the close-by altitude bearing. I found it necessary to offset this by using a slightly different tension positioning on either side of the tube assembly.

What could improve this arrangement? It was obvious to me that moving the central pivot bearings up or down on the tube assembly would require a complete disassembly of the scope. I'd already been through that before when putting in some flocking paper; I did not relish doing it ever again. So I would have to use a variable counterweight that could be positioned on-the-fly, on the telescope tube assembly.

I had read about a system someone once devised, using a little bag of shot and a magnet. Testing the telescope tube, I found that it was indeed ferrous (a steel alloy of some type?) so a magnet would adhere to it. But, FINDING the blasted parts were the problem. I went to several stores and contemplated all sorts of arrangements. Shot was impossible to get. I thought of substituting lead weights used for fishing line; but they were costly. Enough weights to work would set me back at least twelve to fifteen dollars; and I still had no "bag" to hold them, and no strong magnet. By the time I found all the materials necessary, I calculated that I'd have to spend over $20 just for a 'movable' counterweight; and to get my wife to take off time from her teaching to help me sew up the bag for the shot pellets, and figure out a way to attach the magnet (with some form of glue, I presumed.) This would take DAYS of work.

I had despaired of finding an easy method, and was trudging out of a local store, disconsolate and discouraged (I hate building things!) But I happened to pass by the sporting goods department, and saw an assortment of exercising weights. Why not take a look? So I meandered up and down the aisles and finally focused on the weights used by joggers. I found a cheap package containing 3 pounds of wrist weights in nice black fabric pouches, held together with Velcro strips. If I could figure out a way to get these weights to be movable along the tube assembly, I'd solve my problem. I assumed that a bungee cord might work, if attached to each of the bags of the two wrist weights. So I purchased the pack, which cost less than $12 at Wal-Mart: a Danskin WM-2512R 3-lb pair. Each weight is only 1.5 pounds, so I found it necessary to use both of them on my telescope tube assembly to improve the balance. My wife took off a few minutes from her emailing to sew the ends of a flat bungee cord onto the flaps of each of the two weights, after I measured the exact size necessary for a tight fit.

Ideal balance turned out to be achieved with both weights UNDER the tube assembly, one of them above the central pivot and the other one half-way down the remaining distance toward the primary mirror. For the picture shown here, I have rotated that weight onto the top of the tube assembly so that the arrangement would be visible. By means of the tension of the bungee cord I could place each weight so that it was slightly rotated to offset the positioning of the focuser and finder, on the opposite side of the tube, just clearning the rocker box sides. In a few minutes I achieved the best balancing arrangement, allowing me to use the LIGHTEST spring tension on the altitude bearing, yet preventing the scope from falling to the horizon when pointed low, or becoming stiff when pointed high. The improvement in the ease of altitude positioning control was quite remarkable. And the small amount of bearing spring tension allows one to change eyepieces without rebalancing: I can switch from my heaviest 2" barrel ocular to a lightweight 6mm focal length 1.25" barrel Plössl without having to fuss with the position of the counterweight.

Part Four: Replacing original plastic altitude bearing pads

Further use of the telescope at my regular observing sessions confirmed that the azimuth bearing system was now, for all practical purposes, ideal: with exactly the right tension; no stiction; smooth motion, even at 300+ powers of magnification. But the "stock" altitude bearing pads, even with reduced spring tension, still had a small amount of stiction, which made it somewhat hard to re-center an object at high power. I visited the Orion Telescope Center store in Cupertino and experimented with equivalent Orion dobs on display: some were better, some almost as stiff; but all had far less stiction. I discussed this with manager Ken Sablinsky, who called the Watsonville headquarters and determined that there was no part number for the bearing pads: they were not available, except in a new telescope. I was on my own!

Perhaps the best solution would be to order some Teflon pads from an ATM equipment supplier. I put this thought in the back of my mind, and determined to try to do something immediately, with materials on hand. The bearing pads do NOT appear to be authentic, high grade Teflon. They measure a little more than 5/8" square, and are slightly under 1/8" thick. The material seems to be two cemented layers of plastic, one with a slightly whiter surface on top where it contacts the plastic bearing of the tube assembly. A closeup examination revealed that my pads were badly worn and scuffed, with specks of black plastic (or dirt) embedded, hard to remove even with a variety of non- damaging solvents. Each pad was merely stapled to the pressboard, and some were slightly offcenter. They came off immediately with slight pressure at the side, using a blade screwdriver. I decided to remove them and to experiment with replacement material.

After trying several fibre materials that had too much "give", I settled on some densely woven rug runner, backed with rubber. As shown above, the original four bearings are on the right of the table top. On the left is the rug runner material purchased at Orchard Supply Hardware a few years ago, a remnant left over that I cut into four square pieces the same size as the plastic pads. I used a very small amount of 3M contact cement to place them exactly over the centers of the staple-holes for the original ones. The scope tube would now rotate up and down in altitude, stopping almost instantly when pressure was removed with no bounce or backlash. More important, there was no startup "stiction" that would cause the highly magnified view to jump. Success!

I tried the scope at home that night, viewing Saturn and Jupiter at high magnification, finding it easy to track the planets now at the highest practical magnification. Two nights later I used the telescope at my mountaintop observing site, and employed my 6 mm eyepiece (200x) and even my 3.7 mm ocular (322x) for many observations, having little difficulty in moving the scope as the objects drifted through the field. All in all, the improvement of the telescope pointing was beyond expectation: as smooth as could be desired. This is especially important to me, as I like to use very high powers to try to discern the central stars of planetary nebulae, and to see very small angular diameter faint galaxies, often requiring far in excess of 200x. The optics of the telescope can deliver great views at high power when the atmosphere is steady. Now I can spend far more time observing and a lot less time struggling to point my scope, while making critical observations.

My Attitude About Modifications to Commercial Gear

I am definitely a modifier skeptic. Most of the time, commercial products are designed and tweaked better than typical users could do on their own. But sometimes after living with a product for a while -- and I had used the Orion Dob for almost two years! -- I decide to bite the bullet and make needed improvements. They almost always have unintended consequences. The 'simple modification' turns into a nightmare of fussing that can go on for weeks, or months -- and sometimes you never achieve complete satisfaction, or really create an improvement that is totally worthwhile. BE WARNED that unless you find it absolutely necessary to change your telescope or optical product -- nullifying its warranty! -- that you have considered all the other options. In my case, the scope was out of warranty; the smoothness of its pointing had deteriorated badly (almost to the point of uselessness); and I had prior experience with a superior, home-made mount that had greater latitude of adjustment, and none of the design limitations. I knew what it would take to create a meaningful improvement (though I am very tired of building and tweaking things like this, which is why I bought a commercial scope in the first place -- after more than twenty years of fiddling with home-brew instruments.) Remember that you might try to follow my procedure and end up WRECKING your scope! Don't try, if there is even the slightest chance that you can't complete the modifications, and any necessary changes required for your specific situation, to a final satisfactory result. And, expect the UNEXPECTED!

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First part: Thursday 18 April 2007 at 2:54 pm; second installment last edited on Sunday 30 September 2007 at 12:31 pm. Copyright © 2007 Stephen R. Waldee - All Rights Reserved. All Trademarks or Copyrights are © or Property of Their Respective Copyright Holders.

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