This page contains restoration information for the Meade 826 reflector telescope first manufactured by Meade in the late 70's. Both the restoration of my telescope and the information provided by others will be archived here in an effort to help anyone seeking to restore an 826 or one of the other Meade reflector's 591, 628, 645, 826, 826C, 856, 880, 1060, 1266. For links to other restoration sites, vendors, technical info, etc... click here.  For additional details and many more pictures of the 826 restoration, click here. As of October '08 there is now a problem locating replacement synchronous motors for the 826. If you have knowledge of someone still selling them please email me so I can post that info here.

I purchased my 826 new on 10/27/80. Along with much darker skies than we have today, I also found I didn't have to travel far to find an area that allowed me access to most of the horizon, very little street lighting and privacy, lot's of luck doing that today. I had opportunity to use the scope quite often up until 1986 when other interests and work curtailed most of my observing efforts. The last time I actively used the 826 again was not until the fall/winter of 1996.

In early September '04, I decided to bring the 826 out of storage and refurbish it where needed. I quickly encountered several problem areas but considering the age of the telescope this is to be expected. One issue involved the studs and acorn nuts used to connect the spider vane to the tube. I hadn't uncoupled them since I bought the scope. And despite my best efforts to carefully separate them now, the studs literally crumbled into pieces when I tried to remove the acorn nuts. It turns out that Meade had used cast aluminum for the studs. Cast aluminum obviously can be rather brittle.

Unfortunately the original studs were no longer available from Meade, forcing  me to fabricate my own. I was able to do this by going to the Home Depot and purchasing 1/4" thumb screws which turned out to be very close in overall size to the original studs Meade used. I filed one side of the bolt head a bit more flat and drilled and tapped this end for the retaining screw which holds the stud to the vane (you'll need a 6x32 tap, click here for more info on how to do this). The images above show the new stud (in place and connected to the spider vane and tube) and 2 of the original broken ones. The Home Depot also had steel acorn nuts to replace the old ones. I could now reinstall the original spider vane. (In this case it's best not to use dissimilar metals like aluminum and steel together, make sure both bolt and nut are steel.)

While I had the spider apart I discovered that the secondary mount was not in the best condition. It seems the plastic mirror housing is one size while the metal hub it bolts up to is another. You can see cracks in the housing right under and above the screw. This is from being undersized and being forced to fit a slightly larger base. Over time the stress split the plastic. The metal hub of the spider also shows stress cracks so for safety's sake I planned on buying another spider.

Once I had taken the secondary housing apart I found that Meade used what appears to resemble "white gift wrapping tissue paper" in the internal space on the secondary's housing, probably rather common back then. Once the hub was secured to the housing, the paper compressed and in doing so, holds the mirror into place. This method is hardly adequate as any jarring of the tube could easily change the position of the secondary mirror enough to ruin collimation. It also creates uneven pressure points on the mirror and from what I've read, secondary mirrors are just as prone to distortion as primary mirrors are. Instead I decided to use a dab of silicone at 3 points to "hold" the mirror to the plastic housing more securely. This helps eliminate the possibility of the mirror moving around as the scope was transported and subject to vibrations and hopefully will not induce any distortion into the secondary mirror.

I then started work on the 8" primary mirror. Twenty four years is a long time to expect a mirror to hold up, but it wasn't in real bad condition all things considered. I eventually got the opportunity to have the mirror itself tested. Both Ronchi and Foucault tests were performed. The Ronchi ("Ron-key") test showed a turned down edge, add to that a abysmal 1/2 wavefront. (This means that it has a 1/4 wave surface.) The wavefront number is the important one. And we still have to add in the affects of the secondary mirror and the eyepiece which all come into play to affect the final image, but I was already at a disadvantage with a poor quality primary.

The numbers and values assigned to a mirror can be confusing. Wavefront, surface wave, wavefront error, RMS, P-V (peak to valley), Strehl and the ever popular "diffraction limited" and more.  I've been told that some of the better quality reflectors of the 50 and 60's were noted for great optics but these days many mirrors fail to achieve 1/4 wave surface accuracy. Perhaps since Meade was just starting production when I bought my telescope and their quality control was not up to speed yet. Whatever the problem, I would have to replace the primary if I wished to get the best performance from my scope.

A 1/10 wave surface mirror would be nice as some astronomers say it theoretically means you'll see objects about as well as you can, provided atmospheric conditions are very good. So my options are pretty much to replace the mirror with another one (take my chances) or create another one by doing the grinding/polishing myself. If you wish to learn more about wave front, surface accuracy, RMS, peak to valley and other measurements used to grade mirror quality just search on Google. Be forewarned however that it gets technical. Some mirror makers may purposely use misleading terms to confuse you (wave front versus wave surface) values in an effort to sell you a mirror. Click here for links and more info concerning mirrors and how they are rated.

A soaking in a mild detergent helped loosen the dirt and dust that had accumulated on the primary over the years, the scratches (sleeks) imparted from improper cleaning years ago unfortunately will remain. I replaced the cork spacers used to insulate the primary from the metal mirror cell with new cork and repositioned the mirror in the cell.

Once the mirror was cleaned, I set out to find true center on the mirror for collimation. I first located the approximate center of the mirror by using the method described in this article http://www.deep-sky.org/mod.html#Notes on Collimation. Instead of using a scissor to cut a hole in the paper, I used a small nail to punch a hole through the paper and then used a fine point marker to make a dot through the hole onto the mirror.

At this point I divided the mirror cell up into 6 equal sections. Then with the help of a tool (depth gauge) the true center was then found by moving the ruler w/the sliding clip set at 4 inches, around the mirror to those 6 marks as I marked the center of the primary mirror each time with a fine tipped black magic marker. I measured everything again one more time just to make sure I hadn't made a mistake in measuring. I then made a larger "dot" out of all the smaller ones.

It turned out that I was never more than a fraction of a mm off center on any of the 6 marks. This extra effort made it easy to find dead center. I then placed a loose-leaf paper hole reinforcement; which had been blackened; over the center dot.

From what I've read, you could be off a mm or two from true center on a mirror this size and it wouldn't be too critical for collimation. I believe the error factor is 1-2%. Once you've marked your primary mirror it will make collimating very easy to do, even without a laser or other store bought collimating device. I only used a 35mm film container in the fashion documented on so many Web sites. I immediately noticed the difference between this collimation and the one I had done previously w/o the benefit of finding true center and marking the primary mirror. Any effort to collimate will produce better viewing results but the better your efforts, the better the viewing will be. Listed below are some of the sites I found helpful for their info on collimating the optics.
 

http://www.bbastrodesigns.com/howtoalign.html http://w1.411.telia.com/~u41105032/kolli/kolli.html http://w1.411.telia.com/~u41105032/myths/myths.htm http://www.oarval.org/StarTest.htm http://home.att.net/~dale.keller/atm/newtonians/notes/diagonaloffset.htm http://www.fpi-protostar.com/collim.htm

http://www.propermotion.com/jwreed/ATM/Collimate/Collimate.htm http://www.rochesterastronomy.org/main.asp?section=8&page=34 http://www.catseyecollimation.com/mccluneytext.html http://www.astunit.com/tutorials/startest.htm http://www.piesportobservatory.de/english/test.htm http://www.vvm.com/~piscescs/collimat/NoTools2.html

The biggest problem that I encountered during the restoration was with the synchronous motor. Most of the teeth on one of the gears had broken off rendering the motor useless. Meade supplied their drives with motors manufactured by either The Bristol Saybrook Co. or Cramer Co., both headquartered in Connecticut. The motors were rated as 1/10RPM, 120V, 60Hz, 4W. When connected to the worm it allowed the worm gear (clutch) to turn at 6 RPH. The worm gear has 144 teeth so it will make one full revolution every 24 hours.

The damaged I found inside the motor was to the last reduction gear which connects to the drive shaft gear. This gear had 60 outside teeth and 12 inside ones. I say "had" since as you can see below, only 4 of the 12 teeth remain on the part of the gear that connected to the drive shaft output gear of the motor. At first I looked for a replacement gear itself, knowing that Meade no longer stocked the original motor, but nothing came close. Eventually I did much better and actually found a seller on eBay who had purchased a large amount of original inventory from Meade when they cleared out their old parts inventory. Among the parts he purchased was the original 826 motor!

Unfortunately, while many of us took advantage of his inventory over the years, as of October 2008 I started getting emails concerning the eBay URL I had listed on this page where you could find the motor. Everyone told me that the motor is no longer available. I then contacted the seller and he told me that he had sold out all of the inventory he purchased. I've searched and searched but so far have not found anyone else who sells the motor.

Another site that sold the original Meade 826 motor in 2006 was: http://www.surplusshed.com/pages/item/m2058.html. This one also carries other surplus gear from lens to motors, fiber optics, solar panels, cameras and whatever they can get a good deal on. However, as of December '08 I've now learned that they too have exhausted their inventory and they don't believe they will be getting more of these motors. I'll leave their URL above for a while in the hope that maybe they will be able to find more stock but it indeed looks grim for finding a brand new replacement motor if you need one for your 826.

Another option is to post a request for help on the  http://tech.groups.yahoo.com/group/classicmeade/messages The group is composed of Meade enthusiasts and perhaps someone will be able to help you. I'll keep searching and will post the info here and on the Yahoo message board if I can find a new supplier of the motor. (The only other choices may be to buy a motor like that listed below for a Dynascope and modify it to work. This will require a bit of effort on your part, machining and adapters will be necessary. Or, you can have one custom rebuilt from your old one, expect prices to be in the +/- $150 range.)
 

The backs of the original motors are shown above. From what I've been able to find out, Meade initially used motors from the Bristol Saybrook Company on these reflectors. In the mid 80's Meade started using motors from Cramer Company. These were the EXACT same motor, just a different company name.

After installing the new motor I had to settle for testing the motor indoors due to inclement weather. But tracking was pretty much on target using household AC. I found the motor ran about 1 minute fast after 3 hours of tracking. I've also tried using a inverter, running off a 12 volt battery, without any modifications to control the 60 Hertz signal. It ran about 2 minutes slow after 2 hours. Either setup would be adequate for visual observation and a lot easier than nudging the scope along in RA to follow whatever your viewing, especially at higher powers.

When the weather finally cooperated I set up the telescope outside and roughly aligned it with Polaris. I found the tracking to be quite close despite strong winds, strong enough to force me to lock the DEC in place or the tube would move from the wind gusts. I'm sure that with a little more effort in alignment I'll now be able to track the DSO's or planets with little adjustment in RA needed. Hardly the two axis tracking that is required for astrophotography but as I said before, it does make it easier to use the scope to follow an object in RA without the need to constantly nudge the scope manually.

Below are two pictures of what the original Meade synchronous motor supplied with the model 826 reflector looked like. The output shaft on the Cramer and Bristol motors is 3/16" and is slotted to mate up to the worm. (I'm not sure whether Meade supplied the Research Grade scopes with a different motor, but suspect they may have. They did come with much heavier and sturdier mounts and weighed a lot more. The drive box is a different looking unit, what mechanics went inside is unknown. If anyone has one of the Research Grade reflectors I'd appreciate hearing from you.)
 

Apogee's stock changes every so often and if you can't find what you need by searching, give them a call at the number listed at the top of their Web site. I've found them to be helpful and prompt in shipping your order.

Two other sites that I found are suppliers for motors:
http://www.herbach.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=HAR&Product_Code=Synchron+-+RPH and
http://www.hansen-motor.com/synch_speeds.html#anchor1060923

Motor prices are in the $17 range plus shipping. If you have a synchronous motor but it's not listed at these sites, try searching on http://www.thomasregister.com/ You will need to register to use this site. I've found it quite useful and highly recommend it for one stop searching. If you have any other favorite sites let me know.

If you are looking for help with your Dynascope, try the The Criterion Dynascope Group at Yahoo's groups. Great group of people, who love their hobby and their scope! http://groups.yahoo.com/group/dynascope/messages If you need help with your restoration, this group is very helpful, active and well worth checking out. As of March 2008 one of the members of the Dynascope Group has come up with a solution to using the above mentioned motors with a Dynascope, an adapter. You can use the URL I've provided as a starting point for more info on this adapter or search the archives. His Yahoo! ID is kenpo30078 (Ken Poshedly). As hard as it to sometimes find parts I'm sure many people will be very happy with Ken's efforts to allow them to replace their Dynascope motors effortlessly. Here's the URL - http://groups.yahoo.com/group/dynascope/message/7523?threaded=1&var=1&l=1&p=12  You'll have to contact Ken for the latest info on availability and pricing.

One of the things that makes any restoration or modification project tough at times is the inability to find parts. Original parts are sometimes no longer available forcing you to make modifications. Even a simple mod may require the builder to look high and low for a distributor of the part he wishes to use. Our hobby is not unique by any means, but at times finding something as simple as a focusing knob, at least one that fits your particular scope, may seem almost impossible. With that last thought in mind, I'll plan on listing as many links to Web sites offering services or products for the amateur astronomer as I can find. If you have favorite sites or businesses that have helped you with your restoration and mod projects, let me know about them.  This Web site is going to be geared to helping others interested in astronomy to better enjoy the hobby. Your input, restoration oriented or otherwise, will be greatly appreciated.

When I started putting together this Web page on 9/25/04 my hope was to assemble information from not only my own 826 restoration but links to many other restoration projects including, Meade, Dynascope, Parks, Cave Astrola, Star-Liner, Edmund, Coast Instruments and Crown Optics as well as any interesting sites that may help you with your restoration. Things were going well until a HD crash in early June '05 deleted most of my work (I had backed up only a little of the original work). It took a long time but I finally reconstructed the original web page and researched all the links again. I've since uploaded a lot of new files and even got around to dividing the homepage into subdirectories for faster loading and better indexing, just haven't uploaded everything yet. Hopefully my efforts will help someone with the restoration of their telescope. Over the years I've received emails from people in the U.S. and even from other countries who have found this site, so I know that there are others interested in the Meade 826. Feel free to write to me and let me know what you think of my web site, where it can be improved, mistakes to be corrected and of course any help you can offer with restorations. I'll give full credit to you for your efforts. - Louis