Updated 8/2/2000         LX50 to LX200 Conversion Page    Updated 8/2/2000 
Hello and welcome to my LX50/LX200 conversion page. I have just completed the process of putting my 8" LX50 OTA on a 12" LX200 drive base, Meade says it couldn't be done (what do they know!).

First some background, my name is Peter Proulx.   I am a newcomer to astronomy and started out about 2 years ago with casual summertime observing in my back yard (naked eye).  Let me give you a little background on myself,  I am 41 years old and own a local Computer Integration company in the Buffalo/Niagara Falls area.   We are involved in all aspects of computers and data communications.  I have a wonderful wife and 2 great kids Jaime(14) and Joel(10) (click here for some pictures), we currently live on a 17 acre farm just south of lake Ontario.  The skies are great with just a hint of light pollution to the south of my location.  My location is great for observing!

A good friend gave me a ETX90 for a Christmas present last year and I was on my way to some serious observing or at least I thought!  I got hit with the bug pretty bad and started to read as much as I could on astronomy. I soon found out that there are plenty of places to spend my money.  The first place I started to look was at a bigger scope.   The LX50 caught my eye because of the aperture and its portability. In checking out dealers I talked to Roger Tuthill (Tuthill Scopes) he recommended a trip to Stellafane to check out what was available. So off I went, there were all types of scopes at this convention, unfortunately the the weather did not cooperate and we didn't look at one object!  Now Stellafane has a swap meet, so with cash and a check book in hand I was out to buy something.  Plenty of bits and pieces of telescopes a few decent OTAs but nothing worthwhile.  After 2 hour I spent 50 cents on a piece of red cellophane!  Dejected I headed out to grab some lunch and low and behold in the parking lot was a beautiful 8" LX50 with a for sale sign. To make a long story short a $1000 later it had a new home! 

lx50pic1.jpg (22698 bytes) Here is my baby before the operation!
Shortly after I started using the LX50 I came across a 12" LX200 drive assembly, super wedge and heavy duty field tripod for sale on ebay.   The only problem was it was located in Switzerland.  I bid $800 and won the bid, UPS had it here within 4 days ($300 shipping).  If things work out I will have a 8" LX200/50 with Super Wedge and Heavy Duty filed tripod for around $2100 plus my time.  I have detailed with photos and text the conversion process.  It was apparent that with a little machining the DEC motor assembly would fit into the 8" LX50 fork arm and the fork arms would attach to the drive base without any alterations.  Now I am not a big goto proponent but this conversion may be of interest to LX50 owners who would like to add motorized slew capabilities (beyond micro slew).  You could buy components from Meade and with some ingenuity and at least add slewing if desired.  While I had the 8" forks at the machine shop I had them do a roller bearing upgrade as noted on Doc "G"s page.
lx200base.jpg (21396 bytes) LX200 with 12" fork arms and base.  Tested it for slewing all seems to work well!
LX200 DEC Drive assembly:

lx200drive.jpg (21168 bytes)

 The differences between the LX50 and 200 fork arms:

lx fork arms.jpg (22392 bytes)
The LX50 at the start of the LX-ectomy:

lx50pic2.jpg (22199 bytes)

 

LX50 fork arm with roller bearing mod and machined for DEC motor. 

Here is a picture of both arms with bearings. I also transferred the handles from the 12" forks to the 8" forks. The modification required the elimination of "nubs" in the 50's fork arm on the fork that received the DEC Motor assembly.
The alignment process was going to be critical to this process. If you read the DEC bearing mod on Doc G's site alignment is based on marking the fork arms before they are removed. Since the these fork arms were never on this base I squared the fork arms by mounting the base on a tripod. I then used a level at various points on the forks. I then used shims to adjust each fork level to the base.
After leveling both forks I checked for alignment of the DEC axis. 

With the final pre-alignment done I marked the fork arm that would receive the DEC motor to the base.  I then removed this fork are so I could install the OTA and begin final alignments. The picture to the left show the final pre-alignment.
1. Innner Clutch plate installation 2. DEC gear installation
3. Outer clutch plate installation 4. DEC motor assembly installation
OTA alignment required the use of 4/40 screws on the OTA trunions. These would be used to move the OTA to center it on the fork mount.  The Base is leveled and the OTA is leveled vertically and locked in place.  The DEC setting circle was installed at this time and locked in at 90 degrees. A bright light is placed above the OTA.  A short focal length lens is used to centered a beam of light on the RA bearing.
This provides a rough alignment.  I was ready to see if my conversion was worth it. When I first used the "LX250" the alignment was consistently off outside the FOV of a 40mm eyepiece.  I was a little disappointed to say the least.  

But my fellow Amateur Astronomers from the MAPUG group came to the rescue! 

I used a OTA alignment procedure developed by Mike Sparks that utilizes a laser pointer.  This procedure is amazing my accuracy is improved to dead on when the scope is leveled and aligned alt/az or polar. 
This was an interesting experience and I recently purchased a MX5C one shot color camera and look forward to imaging.  The Super Wedge and Heavy Duty tripod were a bonus with the base. Look to my WEB page for further updates.  Email me with comments: pproulx@premcom.com

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