Now I get it. Your lower bearing was stuck in the upper part. This
can happen with those scopes that are assembled on a Monday or Friday
afternoon. :-)
With all of the trouble you have had, I assume you have one of those.
However, your experiences are of value since they have provided a
training ground for others who may at some point experience the same
problems.

Doc G

>
> In a message dated 9/30/01 9:22:30 PM Eastern Daylight Time,
>
> <<
> Well, now I do not understand. There are some pictures on my web site
> about this. But in words, you first take off the cover plate on the
> fork. Then you remove I screw and take of the fender washer. Then
> you go into the bottom and tap against the gear mounting plate until
> the base comes off. The two bearings will come off at the same time.
> It is wise to take them off at the same time so that the bearings do
> not get jammed.
>
> See the photos on my wed site. at Mechanical Analysis
>
> Doc G >>
>
> Okay, Doc,
>
> I think the problem perhapos was in my termonology. If we use your upper
> left picture on your page, we see that the lower RA bearing is still mounted
> on the lower section, with its inner race resting on the 'cone'. However,
> you can also see that when the lower section is joined to the upper section,
> the outer race of the bearing will slide into a 'ring' that is just below the
> RA gear, and that ring is in the upper section.
>
> In my case, when the upper and lower sections were separated, my lower RA
> bearing did NOT stay on the 'cone', but instead, the outer race was snugly
> held in the 'ring' below the gear. It was a very tight fit, in fact. The
> only way to get the bearing out of that 'ring' in the upper section, was to
> come down through the opening for the upper bearing and tap the lower bearing
> down. That forced it out of the 'ring'.
>
> However, my bearing was so tight that I had to heat the 'ring' to make it
> expand a little, so as to allow it to come free when tapped from above.
>
> Apparently, it is most common for the bearing to stay stuck to the 'cone',
> based on what happened with Scott, and other feedback I got offline. My
> situation was just the reverse. I think that the reason for the difference
> is, when I last had the two units separated, I made sure that the entire
> 'cone' in the lower section was well greased, so that the units would more
> easily slide together. That helped keep the lower bearing from seizing on the
> cone.
>
> Tomorrow, when I install the new lower bearing, I'll not only lubticate the
> inner race, but the outer one as well, and it should slide into the 'ring'
> much easier than it came out. Also, for the past few days, my bearing has
> been in my freezer so as to shrink it a little, and that should make it slide
> into the ring even easier. But before I join the upper and lower units, I'll
> first let the bearing warm up, so as to not be tighter than necessary on the
> inner race to the cone.
>
> I hope this makes sense, and explains why I had to come in from the top unit
> to get the bearing free.
>
> All the best,
>
> Bruce Johnston
>
> Bruce Johnston Computing
> <http://members.aol.com/bjohns7764>
> Internet home for "SuperFix" and "MegaFix" image processing software.
> Personal page: <http://members.aol.com/ccdastro>

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