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  1. Another name is a 'face pin spanner' You can get then in fixed sizes or adjustable.
  2. Hi, I don't think there are many people who have done this because of the limited gains of doing the conversion. Much of the drive inaccuracy and backlash comes from the small gearbox that's mounted on top of the motor. Belts won't improve this area unfortunately. In addition to fitting the belts, it is necessary to reverse the motor and the encoder wiring.
  3. How tight is the mesh between the motor pinon gear and the larger idler gear? There should be a very small amount of clearance. If they are meshed tight it could make the motor is stall.
  4. Hello Bobby, 9 or 10 seconds of backlash equals about 1 tooth of slack on the belt which is a lot. The belt may not have engaged the pulley teeth when you fitted the motor. And now the belt has dropped in to mesh with the pulley teeth leaving a lot of slack. A quick check is to remove the electronic panel. Remove the worm end cover at the bearing ring adjustment end. Take some pliers and carefully rotate to worm shaft a few degrees back and forth. If you then look closely at the very center of the motor you should see the motor shaft turn exactly at the same time the pliers turn the worm. If you feel/see any delay the belt tension isn't correct. (Put a small marker pen dot on the end of the motor shaft, it will be easier to to see the motor rotating). Also check the worm bearing locking ring is lightly snugged up to eliminate any worm end float. As already mentioned, it could be the 12 tooth or 47 tooth pulley grub screws not tight and rocking on the flat of the shaft. Balance doesn't have to be perfect with a belt kit fitted. In fact this is not desirable, just a very small imbalance to keep the worm in contact on one side and not flop side to side as there's usually a small amount of worm-wheel backlash present.
  5. It looks normal to me. On this type of gearbox there is usually a bit of end float from the output shaft of the gearbox. If the mount is tracking & slewing ok, I'd leave it well alone ? You could strip the gearbox apart and fit a couple of nylon washers to minimise the end float but I doubt it would give anything beneficial to be worth the effort.
  6. Hello, The rattling you are are describing is usually caused by the worm gear mesh being a fraction too tight. It's a straight forward user adjustment to make. See Astro-Baby's guide on Worn Engagement for RA Axis on this page - http://www.astro-baby.com/heq5-rebuild/heq5-we1.htm 1/8 turn on the adjustment screws should do it. .
  7. Hello Capt' My 10mm Delos has the field stop in exactly same position, so no problem there. The outer circle in your view should be a sharp black circle ( formed by the field stop ) If the edge circle was 'fuzzy' then I can only guess your eye wasn't close enough to the eyepiece / eye cup too far out which restricted the view ?
  8. 100mm box section is quite small for that height. Stiffening ribs 1/2 way up the sides would needed. But I would recommend using a much large section from the start. It'll give a more rigid set up and future proof in the event of a larger scope comes along
  9. I would turn off PEC correction via the GTO controller too while you're testing this out. I had a 'funny' blip on my mount and the PEC wasn't ok and needed to re-record it. Also do a DEC-RA test run just to make sure backlash isn't an issue. Ray Gralaks Pulse Guide http://www.pulseguide.com/index.html can run this test and give a visual of the backlash performance Good results look like this https://www.cloudynights.com/topic/483600-ap900-dec-backlash/ If backlash is detected check according to this pdf - http://www.astro-physics.com/tech_support/mounts/backlash2.pdf
  10. Hi, Take a look at these videos on YouTube. Skip to 2:04 and note the way the belt behaves when going forward and then in reverse. The bottom side of the belt doesn't go loose when the motor reverses. If you see the belt drop at all, when the motor runs clockwise, then the belt is too loose. Once you have the belt set up properly you'll not want to go back to gears. Some mention the balance has to be perfect with belts. It doesn't have to be. It's better to have a very slight East heavy set up as this will prevent the worm wheel 'bouncing' side to side in the backlash / clearance, the same as you would have with gears. Also try running with a fraction more backlash in the worm-wheel mesh. You may have this set just a bit too tight. This video also shows how much finger pressure is needed to tension the belt - not much needed. Skip to 26:40. The bottom side of the belt again stays straight when the motor first runs @ 27:45 One other point to check is to make sure the belt isn't rubbing heavily on the end of the pulley. This will be due to the pulley not aligned with the track of the belt as it passes past the idler roller. see step 9 in the instructions.
  11. I think Lightbuckets suggestion is right. The mesh is just a bit too close and on a cold night things have contracted a fraction causing the axis to bind. I'd be very surprised if the mount was to freeze. The motors do generate some heat even when stationary and that would probably enough background heat to keep the mount from freezing.
  12. Hi, The double diffraction spikes are from the spider vanes. The opposing vanes need to be in perfect alignment (straight) or you get that effect.
  13. Nicely done. I hope the addition of the bungee didn't over stretch your budget
  14. Hi L B. The adjustment ring touches on the outer race of bearings which presses the outer race against the ball bearings and then on to the inner race. This takes out the natural clearances manufactured in to the bearings. If you over tighten the ring the pressure on the bearing can be such that it doesn't turn smoothly. It can get really 'lumpy' if you really over do it and could be damaged to the point the may not run smoothly ever again Just 'finger tight' is all that's needed on the ring adjustment. The shaft isn't in a fixed position, rather supported between 2 bearings which 'position' can be adjusted.
  15. Hi Spill, The outside of the ring gear needs to be lightly greased too. This is because when the clutch levers are loosened the outer casting and ring gear will be sliding relative to each other. If no grease is present the surfaces will be rubbing and possibly gall up and seize. The clutches will operate fine with the grease.
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