Hello, I posted this question a while ago so you might want to check for those suggestions as well. I ended up getting the Parallax rings specifically for the TOA 150 and attaching them directly to

-Neils. I think the TOA150 is 179mm diamter, so 155 rings wont fit. Parallax makes rings for TOA150. You could use those with the terrific and well priced AP 15inch ribbed plate. I think

Niels, if you do have a plate made one of the most critical aspects you'll have to remember is the "exact" alignment of the holes for the attachment of both the mount and the OTA. You want to

AP makes several plates for the 900 with a variety of bolt patterns. See their website. The AP rings for my AP155 bolt directly to the plate. If you're lucky, the Tak rings might also. If they

I want to attach my Takahashi TOA-150 refractor to my 900GTO. I could purchase an appropriate dovetail and a Losmandy saddle. However, the quick release is not important as this will be a permanent

Hi Rick, I guess I'm spoiled in wanting to use the LED to see the alignment reticle a bit more easily. Besides, it is difficult to spot Polaris most times, and nearly impossible in late dusk,

Hi Dave, I'm glad you corrected my thinking. I had completely forgot the possibility of using it manually, without GOTO. In such case, definitely, a N-S switch would make good sense; it would

I personally would rather have a power switch. That aside, I believe that the AP mounts were designed with many target requirements, one of those being someone doing visual observing with or without

Hi Joe, It's best to have a slight imbalance so that any (small) gear backlash is always pushed out. I prefer the mount always to 'pull' a bit. Clear Skies, Gert

Hi Joe, Here is a point of reference. I use Pasill2,3,&4 models. I can easily line up the two stars from my home. I am right next to LAX airport and do the alignment looking right over LAX and

Thanks Jeff, I had forgotten about the large initial worm stress, with no OTA. I suppose if it can (and must) survive that, then the normal imbalance is no issue at all, in comparison. I had

We are mixing pointing at the pole and pointing at Polaris. If the mount is polar aligned and the telescope is orthogonal then you can do the following. When you point the telescope at the pole ie

Hi Roland, Not knowing the centre of gravity of your (160/F7.5) OTA, but assuming it is at mid point (23.6 inches), that would be approximately a moment of 189 inch-lbs. O.K. that is a useful

supposed to in the options. This one choose the the weakest something this first uses this Noted. I should have followed your preferred methodology you outlined in message 17688. I would have sworn it

Joe -- I accidentally balanced my 600E GTO once without diagonal or eyepiece. When a 2" diagonal, 2" Barlow and T4 Nagler was added, it produced intermittent stalls when slewing (but not when

Hi Roland, This is good news - I was becoming concerned about "meticulously" rebalancing the counterweights, every time I crossed the meridian. Indeed, the AP900 is a superb design, and even

John -- It's quite unlikely to be the motor shaft -- that gear is glued on as well as being set-screwed. The gears in the middle are just transfer gears, so they rotate freely on the

J.Zeglinski@... writes: I have had an imbalance of 8 lb at the end of a 160F7.5 refractor. You will know when the imbalance is too large because the motors will have a problem slewing in

winfij@... writes: There is only one locking screw, and that is on the last spur gear on the worm itself. The other gears all run free on their pinions. You can remove the largest gear in

If your telescope is orthogonal to the mount and the mount is even moderately well polar aligned, when you point the telescope right at the pole, Polaris will NOT be centered. It will be noticeably