Meade LX-200 Superwedge

This is the original Superwedge.  Meade recently released an "upgraded" version, but I am hearing it still suffers many of the same issues.

This wedge can be remarkably stable.  Adjusting the wedge can be a major pain in the backside.  Most of the problems stem from metals rubbing against each other - like metals tend to gall and stick.  The only barrier between the metals is some paint that rapidly wears through. 

Leave the bolts loose enough that you can easily adjust the wedge and it wobbles something fierce.  Tighten the bolts after polar alignment and it shifts the alignment.  Start with the bolts tight enough to be stable and it is almost impossible to adjust the polar alignment.  Neither method is satisfactory and leads to much frustration.

There are a couple of quick and cheap fixes.  Nylon and brass washers are available at most hardware stores (I usually can't find them at any of the national chain home centers).  Adding these washers will eliminate most of the metal to metal contact and allow you to easily adjust the wedge with the bolts snug enough to make the wedge fairly stable.  You may also want to replace the provided bolts, they really are too short to add the washers.  Stainless steel bolts are a stock item in most hardware stores.

Meade ships the wedge with all of the threaded adjustments dry.  A little lube helps a lot.   I tried grease and oil, but since the threads are exposed, neither were user friendly.  I finally settled on Rem-Oil, available at most sporting goods (check the gun department).  When the carrier evaporates, it leaves a dry Teflon lubricant behind.  It does not attract dirt, nor does it get on your hands to be readily transferred to everything else you touch.  It takes a couple days for the carrier to evaporate, so plan accordingly.

Materials
Bolt, Stainless  5/16NC x 1 1/2
Bolt, Stainless 3/8NC x 1 3/4
Washer, Brass 5/16 x 3/4
Washer, Nylon 1/2 x 1 1/2
Washer, Nylon 6 3/8 x 1 1/18
Washer, Nylon 3 5/16 x 1
 

Superwedge Meade only provides one bolt on each side of the altitude plates.  Add a second bolt to each side.  I believe they only ship the wedge with one on each side to ease the adjustment, with the nylon washers it is a moot point.  I had to remove the altitude indicator since it interfered with the nylon washers, but it isn't that terribly accurate anyway.  With some trial and error you will find the ideal tension so adjustments are slick, yet the mount is stable.  I run mine very snug.
Superwedge Don't forget to add a washer to the altitude pivot bolt.  Snug this bolt down tight.
Superwedge Superwedge
I added brass washers on top of the base plate.  Nylon washers small enough to clear the ridge near the bolts tended to bind in the ends of the bolt slots.  These bolts can also be ran fairly tight.
Superwedge Add nylon washers between the wedge and tripod.  Use washers big enough to remain outside of the bolt slots.  Don't forget to add a washer for the the center bolt too.
Superwedge Now comes the hard part.  Meade used a chemical thread locker on all of the nuts and knobs.  Patience, a vise (protect the parts with wood blocks) and sockets are required to take them apart - be careful not to damage the threads on the rod.  The crown nuts only catch a couple threads so both sides need to come apart.  Remove the metal washers Meade used and replace with the thicker nylon washers.  Install the rod back into the azimuth adjuster ensuring equal lengths of the rod protrude on both sides of the wedge.  Run the inside nuts on and install one knob and crown nut.  Tighten or loosen the opposite inside nut to achieve the tension you want, then add the other knob and crown nut.  I did not use a thread locker and have had no issues with the knobs coming loose.

Superwedge The altitude adjuster gets the same treatment.  I added heavier metal washers between the crossbar and the nylon washers to minimize their distortion around the crossbar.

These simple and cheap fixes made a major improvement in my mount.  However, they do nothing to correct the backlash in the adjustments.  The altitude pivot and the altitude crossbar are sloppy fits.  A good machinist and a handful of bushings can solve these.  A totally redesigned azimuth adjuster is required to remove the backlash there.  Check back here for these fixes as I can get them done.

The nylon washers will require periodic replacement, but the benefits of a much easier to adjust wedge far outweigh the minor hassle of replacing them when needed.

When polar aligning the wedge, center Polaris and then remove the tension in the azimuth adjustment, otherwise it will slowly shift until it removes the tension on its own.  For the altitude adjustment you must make the last turns on the altitude knob counterclockwise.  This will remove the slop in the crossbar and prevent an altitude shift when you start slewing the scope around.

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