Hi Janet.

Sounds like your focusing setup is now "in the zone." Good for you.
We've trod the learning path you're following, and although it's a
simple 10-minute procedure, the EZ Focus Kit contains 4 pages
of step-by-step photo illustrated instructions that eliminate the
need for education by trial and error.

With the EZ Focus Kit we've fixed things so there will be no machining,
grinding, or drilling of parts. Although the MAPUG archives contain the
basic approach that we've followed, there was about a man-month of
engineering that went into simplifying procedures and running beta tests
of our setup with volunteers around the US.

Believe it or not, the most difficult part to procure for the kit was
the thrust washer. Thickness, outside diameter, inside diameter
and material are all very important. We wound up having our's
custom stamped out of alloy 316 stainless steel at a specialty
house out in Minnesota.

Although it doesn't sound like good practice, repeated tests show
that there is no significant damage to the brass thread if the focus knob
set screws seat on the thread. But what you've done is fine too,
as long as you have enough threaded engagement so that the
focus knob doesn't wobble when threaded on.

Pete Peterson <peterson-web.com>

-----Original Message-----
Luckas
Sent: Wednesday, June 27, 2001 8:45 PM
Subject: Re: [M]: LX200: Ball bearing focuser upgrade.

Pete,

I'd appreciate your input into the pitfalls of not following a critical
assembly procedure such as that included in the EZ kit. I've found that
these thrust washers can be too tight - to the point where they bind. I've
backed mine off so that there is no slop, but a very smooth action (almost
too smooth, free spinning feel). Is there anything else I should do ?
Seem's unlikely that anything will create wear with this arrangement
(although I do have a thrust washer between the focusser knob and outer
bearing (as recommended on the Mapug / Hart archive).

Also, how have you managed to remedy the situation where you run out of 1/2
inch shaft for the outer thrust washer, and does the EZ Focus Kit result in
the grub screws of the focus knob tightening up on the brass thread. I found
I needed to have 3mm machined from the aluminium sleeve (make sense ?). :-))
to avoid damage to the brass thread when everything is reassembled.

Thanks for you input.


----- Original Message -----
Sent: Wednesday, June 27, 2001 9:00 PM
Subject: RE: [M]: LX200: Ball bearing focuser upgrade.


> Hi Janet.
>
> The bearings are the easy part. Without the properly sized thrust washer,
> grease and assembly procedure you could indeed get wear. Or perhaps
> have to use a file or grinder or drill to make things fit. This is one of
> those modifications that can be done well or be done shoddily.
>
> Believe it or not we've spent close to a man-month of engineering
> developing, refining, testing, and field-testing at our beta test sites to
> insure that this kind of thing doesn't happen with the EZ Focus Kit.
>
> Pete Peterson
>
> -----Original Message-----
Janet
> L Miller
> Sent: Wednesday, June 27, 2001 6:39 AM
> Subject: Re: [M]: LX200: Ball bearing focuser upgrade.
>
> Hi all,
>
> One of the guys in the LX90 group installed the bearings and noticed some
> deformation of the brass bushing and some wear on the aluminum retainer
> after a few weeks of use. Would it be a better idea to use 4 thrust
washers
> instead of the one?
>
> Has anyone that installed this mod taken their focusers apart since
> installing to see if any degradation of the original stock parts has
> occured?
>
> And finally, could the stock nylon washers be used as a replaceable thrust
> washer to prevent damage to the brass/aluminum parts by the steel needle
> bearings? Will the nylon deform faster than the brass? My guess is that it
> would being somewhat softer.
>
> - Jan
> ----- Original Message -----
> Sent: Wednesday, June 27, 2001 1:45 AM
> Subject: RE: [M]: LX200: Ball bearing focuser upgrade.
>
>
> > Here's a link to Torrington's website were you can find a supplier
> > in your area. http://www.torrington.com/contact/
> >
> > Doug
> >
> > -----Original Message-----
> > Paul Luckas
> > Sent: Tuesday, June 26, 2001 7:57 PM
> > Subject: Re: [M]: LX200: Ball bearing focuser upgrade.
> >
> >
> > Well actually it isn't that hard. Any bearing outlet will have details
on
> > these Torrington (and other) bearings. Took the man one minute behind
the
> > counter to find the bearing I needed. As for 'special washer', I used
the
> > thrust washer that matches the bearing (as per M. Hart's original
specs.)
> > and the original plastic washers to fill the recess in the focus knob.
> Works
> > beautifully.
> >
> > Having said that, a kit that includes all of the parts PLUS detailed
> > instructions would certainly suit the faint hearted. BUT, don't be
> fooled -
> > these are off the shelf bearings (literally) which cost only a few
> dollars.
> >
> >
> > ----- Original Message -----
> > Sent: Wednesday, June 27, 2001 2:45 AM
> > Subject: RE: [M]: LX200: Ball bearing focuser upgrade.
> >
> >
> > > Hi Ken,
> > > I feel the price is most reasonable. I just installed the kit. Works
> > > great; backlash virtually eliminated and the feel is very smooth. Try
> to
> > > find the precision roller bearing thrust washers in the correct size
and
> > > more importantly the special washer that fills in the recess in the
> > aluminum
> > > focuser knob and acts as the upper bearing race. It aint easy. This
> kit
> > > comes with clear instructions and installs in minutes. The savings in
> > time
> > > searching for the the thrust washers and special washer and a proper
> grade
> > > of grease is significant and well worth this modest charge in my
> opinion.
> > I
> > > also use Peterson's EyeOpener which permits a full 2" field stop for
> > > unrestricted use of 2" diagonals and eyepieces and that product is
also
> > > outstanding.
> > >
> > > Regards
> > >
> > > Bill Wood
> > > LX200 10" f/10
> > > Phoenix, AZ
> > >
> > > -----Original Message-----
> > > Ken Wilson
> > > Sent: Tuesday, June 26, 2001 8:30 AM
> > > Subject: RE: [M]: LX200: Ball bearing focuser upgrade.
> > >
> > >
> > > $30.00 is a bit steep don't you think for a couple of washers,
bearings
> > and
> > > a glob of grease?
> > >
> > > -----Original Message-----
> > > mapug
> > > Sent: Tuesday, June 26, 2001 9:10 AM
> > > Subject: RE: [M]: LX200: Ball bearing focuser upgrade.
> > >
> > >
> > > Actually this "fix" is so good that we're selling them as kits.
> > >
> > > See www.peterson-web.com
> > >
> > > Pete Peterson
> > >
> > > -----Original Message-----
> > David
> > > Olmstead
> > > Sent: Tuesday, June 26, 2001 12:55 AM
> > > Subject: Re: [M]: LX200: Ball bearing focuser upgrade.
> > >
> > > Paul and others,
> > >
> > > I have done the very same to my focuser and can report a very smooth
and
> > > improved focuser movement.
> > >
> > > Dave O.
> > >
> > >
> > >
> > >
> > >
> >
> >
> >
> >
>
>

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