Hey mate, There is one way to check if your polar alignment is right or not. Sometimes you can think that a program has told you its perfect only to find your out by a country mile! (been there done that). Another issue with using your telescope with alignment software is you are aligning the telescope to true polar south... not the actual mount head just be aware of this.
To test your alignment first, run say a 4-5 min shot, if its PE that is the issue the star will jump around but not drag across the screen, if it drags... back to the drawing board, if not then PE is a culprit.
EQ6's sometimes need some love depending on what time of the week and which apprentice put it together! Your issue sounds to me as if you have excessive backlash!
Checks.
with all the weights and telescope on check the backlash in each axis. eg. Park the scope to home position. grab the CW bar (well not grab but with a few fingers) and try to push it in the RA axis in the direction it would travel normally. How much does it move? If there is no back lash the scope mount will not move. you need a little bit as the gear sets are not perfect they will have PE in them or bumps and errors on the gear sets. If there is back lash you can quickly start determining where it is coming from.
There is 3 areas that it will arise.
1. Stepper motor spur gear - transfer gear.
2. Transfer gear to worm wheel gear
3. Worm wheel within the bearings.
3 is the easiest to check there are black caps on either side of the mount. I believe its the opposite side to the control board (where you turn the mount on) open up that cap you should see a ring with a slot on each side and the worm wheel poking though. if you don't see this its on the other side (be sure to put the cap back in before wiggling the mount.... that cap holds the bearing in place.
Now repeat the first step i said, that is move the scope in RA in a oscillating fashion. look at the worm gear is it moving back and forth? if so get a reasonably large flat head screw driver and while oscillating the tube back and forth just gently tighten the ring. what this is doing is fixing the worm wheel from side to side movement when the mount is tracking.
1. is the next easiest thing to do. When you slew your scope EQ6's generally have a gawd awful crunching sound on start and finish of the slew. this is the meshing between the motor spur gear and transfer gear. to do this you need to have a bit of tinkering skill.... but its not a critical thing, remove the control panel, un clip the wires and sit the panel in a safe static free spot. Use a long Phillips head screw driver and unscrew the motor. you will need a allen key tool to do this undo the 3 screws just you will see that it moves the transfer gear into the spur gear, gently hold your finger on the plate so that it pushes the transfer gear into the spur gear and slightly tighten the cap heads as not to push out your meshing. Check to see if you have done it right by looking at the back lash, move the transfer gear back and forwards slightly. once you are happy with it tighten down the screws properly, with the back lash you want a tiny bit not much or just enough so that you can rotate the transfer gear by hand and its just easy to move. you might as well do both axis while your at it!
Before you put the motors back in, grab your pointer finger and put it on the actual worm wheel gear that is just poking though, try and move the mount turn that wheel if it is tight. thats not so good if you can feel it slopping thats not so good either if you can just turn it so it is firm but not impossible to turn then thats the sweet spot!
Before you put the motor back together, hold onto the plug at one end and twist the wires until they form a nice twisted braid and hold them all together in one cable.... thats a whole other story behind why mine are like that now! Put the motor back in and with no special care, just make sure the motor push's nicely into the worm wheel gear (you can check the mesh by the little silver inspection port on the side use a flat head screw driver to remove). put it all back together, turn the mount on and look though that inspection port, turn it to speed 3, and then look at the gears, do they move when you say move? if not you have Number 2 back lash Not in itself hard to do, but it requires a whole lot more work and includes stripping the whole mount down! PM me on that issue!
Sorry for the huge post, but theres no easy one liner here. I have pulled my mount apart plenty of times now and know them back the front and how to tune them up. Done right these mounts are really good, I can do a meridian flip and land the target on the ccd chip but it is tuned and polar aligned within arc seconds of the pole further i have seen them guide a F9 scope for 10 min with round stars. Capable in the right hands!
Brendan
If you want a full guide on how to set a EQ6 up properly (not talking about just the level it and what not but the actual markings and home position) then duck into the resource page on my website the link is in my signature.
