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Date: 20 Jul 2006 21:27:26
From:
Subject: New Meade 2045 user - basic knowledge issue or mechanical problem?
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I've just acquired a Meade 2045 and seem to be having problems w/ the
Right Ascension Slow-Motion control (or I'm just clueless - a distinct
possibility at this stage)
When the scope base is sitting flat on a table (ie, mini tripod legs
not attached), w/ the RA lock in the unlocked position, I turn the RA
slow-mo control and the fork assembly turns on the base, w/ the RA ring
remaining stationary wrt the base. When I attach the tripod legs, w/
the fork/scope now at an angle to the table, I turn the RA slow-mo
control and the RA ring turns, but the scope and base remain stationary
- the RA slow-mo control doesn't seem to have the 'grip' to actually
turn the scope when the weight is not directly centered over the RA
axis.
So, is this something broken or needing adjustment, or am I not
understanding the purpose of the RA slow-mo control? (I thought that I
should be able to use that to search a small area of sky through right
ascension, vs manually grab and position the fork wrt the base - that
can't possibly be the way its done...)
Thanks for any assistance!
Jim
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Date: 21 Jul 2006 09:33:52
From:
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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Funny you should bring that up Rod... I'm in a "Your membership is
awaiting approval by the group owner" status as of signing up for the
sct-user group last night.
If you get a chance to approve me, I'll be well on my way to being in
serious debt to you! :-)
Thanks Again!!
Jim
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Date: 21 Jul 2006 09:24:22
From: RMOLLISE
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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bob wrote:
> I had a trusty 2045 as my first scope for years. A very underrated, simple
> little scope. I loved it. I don't recall ever running into that problem, but
> do remember taking apart the RA gear assembly once, possible just to see how
> it worked or to lube it. Did you try screwing the legs in, but just a few
> turns? In other words, is it the incline, or the perhaps the threads on the
> legs compressing something?
>
Hi:
That's a very good suggestion indeed.
As for the 2045...no it was not a bad little scope. I've never thought
the optics were quite as good as those of the C5, but they were usually
not bad. I particularly liked the fancy LX3 version, and it was
certainly better than the B&L/Criterion 4-inchers.
Peace,
Rod Mollise
Author of:
Choosing and Using a Schmidt Cassegrain Telescope
and
The Urban Astronomer's Guide
<http://skywatch.brainiac.com/astroland >
The Annual SCT User Imaging Contest is Underway!
<http://www.rothritter.com/contest/2006/ >
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Date: 21 Jul 2006 12:52:19
From: bob
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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"RMOLLISE" <rmollise@hotmail.com > wrote in message
news:1153499062.119175.231220@i42g2000cwa.googlegroups.com...
> As for the 2045...no it was not a bad little scope. I've never thought
> the optics were quite as good as those of the C5, but they were usually
> not bad.
Was the C5 the cute little beasty with the helical focus? I liked that
scope.
--
Bob
Travel and Astronomy Photos
http://www3.sympatico.ca/bomo
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Date: 21 Jul 2006 09:22:18
From: RMOLLISE
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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jims.65311@gmail.com wrote:
> Hi Rod - first, thanks for the reply - I'm a bit overwhelmed that I got
> a reply from Uncle Rod himself! :-)
>
> I'd tried partially tightening the RA lock, figuring perhaps the
> mechanism worked like the declination, where something had to be
> 'engaged' in order for the slo-mo knob to work. That didn't seem to do
> it, though I was a bit hesitant to put much torque to the knob in this
> partially-locked position for fear of stripping something.
>
Hi Jim:
Since I don't have a 2045 around here to refer to (haven't seen one in
a few years, not even the latter day 2045D), I suggest you check into
my SCT User Yahoo group...I'd guess someone there will be able to help
you out in no time.
Peace,
Rod Mollise
Author of:
Choosing and Using a Schmidt Cassegrain Telescope
and
The Urban Astronomer's Guide
<http://skywatch.brainiac.com/astroland >
The Annual SCT User Imaging Contest is Underway!
<http://www.rothritter.com/contest/2006/ >
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Date: 21 Jul 2006 07:21:27
From:
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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Hi Rod - first, thanks for the reply - I'm a bit overwhelmed that I got
a reply from Uncle Rod himself! :-)
I'd tried partially tightening the RA lock, figuring perhaps the
mechanism worked like the declination, where something had to be
'engaged' in order for the slo-mo knob to work. That didn't seem to do
it, though I was a bit hesitant to put much torque to the knob in this
partially-locked position for fear of stripping something.
It all works just dandy when the scope is sitting flat/upright on a
table - the lock lever locks it all in place - can't turn the fork by
hand, can't turn the RA knob. When the RA lever is unlocked, turning
the fork by hand causes the knob to spin, and it doesn't skip any teeth
- I've made a complete revolution to check that. The RA ring can be
positioned by pushing it with opposed thumbs (scope and base don't
move, just the ring, which is my understanding of how that should
work.) Its just when the scope is put onto the tripod legs, at an angle
to the horizontal where the weight of the scope/fork is off-center,
that turning the knob results in the RA ring spinning, but not the
fork/scope. Definitely seems that the offset weight is just too much
for something inside to 'grab' and turn the fork.
The prior owner suggested partially locking the RA, too, so I'll
definitely experiment a little further with that.
I've considered pulling the pivot screw in the middle of the fork and
easing the assembly off to take a look at what's going on between the
fork and the base (I've already learned that there's nothing in the big
bottom cavity other than the drive motor and PCB for the motor...) But,
before I start digging too deeply into guts, I wanted to establish if
there's an actual problem or if its just a dumb user issue...
Thanks again for the help - if you have any additional suggestions, or
can think of anyone who might know about the internals, I'd be very
interested to hear about it!
Jim
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Date: 21 Jul 2006 11:57:12
From: bob
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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I had a trusty 2045 as my first scope for years. A very underrated, simple
little scope. I loved it. I don't recall ever running into that problem, but
do remember taking apart the RA gear assembly once, possible just to see how
it worked or to lube it. Did you try screwing the legs in, but just a few
turns? In other words, is it the incline, or the perhaps the threads on the
legs compressing something?
--
Bob
Travel and Astronomy Photos
http://www3.sympatico.ca/bomo
<jims.65311@gmail.com > wrote in message
news:1153491687.160604.242370@i42g2000cwa.googlegroups.com...
> Hi Rod - first, thanks for the reply - I'm a bit overwhelmed that I got
> a reply from Uncle Rod himself! :-)
>
> I'd tried partially tightening the RA lock, figuring perhaps the
> mechanism worked like the declination, where something had to be
> 'engaged' in order for the slo-mo knob to work. That didn't seem to do
> it, though I was a bit hesitant to put much torque to the knob in this
> partially-locked position for fear of stripping something.
>
> It all works just dandy when the scope is sitting flat/upright on a
> table - the lock lever locks it all in place - can't turn the fork by
> hand, can't turn the RA knob. When the RA lever is unlocked, turning
> the fork by hand causes the knob to spin, and it doesn't skip any teeth
> - I've made a complete revolution to check that. The RA ring can be
> positioned by pushing it with opposed thumbs (scope and base don't
> move, just the ring, which is my understanding of how that should
> work.) Its just when the scope is put onto the tripod legs, at an angle
> to the horizontal where the weight of the scope/fork is off-center,
> that turning the knob results in the RA ring spinning, but not the
> fork/scope. Definitely seems that the offset weight is just too much
> for something inside to 'grab' and turn the fork.
>
> The prior owner suggested partially locking the RA, too, so I'll
> definitely experiment a little further with that.
>
> I've considered pulling the pivot screw in the middle of the fork and
> easing the assembly off to take a look at what's going on between the
> fork and the base (I've already learned that there's nothing in the big
> bottom cavity other than the drive motor and PCB for the motor...) But,
> before I start digging too deeply into guts, I wanted to establish if
> there's an actual problem or if its just a dumb user issue...
>
> Thanks again for the help - if you have any additional suggestions, or
> can think of anyone who might know about the internals, I'd be very
> interested to hear about it!
>
> Jim
>
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Date: 23 Jul 2006 10:07:26
From: Johnny Borborigmi
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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On 2006-07-21 11:57:12 -0400, "bob" <me@here.ca > said:
> I had a trusty 2045 as my first scope for years. A very underrated, simple
> little scope. I loved it. I don't recall ever running into that problem, but
> do remember taking apart the RA gear assembly once, possible just to see how
> it worked or to lube it. Did you try screwing the legs in, but just a few
> turns? In other words, is it the incline, or the perhaps the threads on the
> legs compressing something?
Me either I still have mine and let a friend borrow it. GREAT little scope!
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Date: 21 Jul 2006 05:46:06
From: RMOLLISE
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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> So, is this something broken or needing adjustment, or am I not
> understanding the purpose of the RA slow-mo control? (I thought that I
> should be able to use that to search a small area of sky through right
> ascension, vs manually grab and position the fork wrt the base - that
> can't possibly be the way its done...)
>
> Thanks for any assistance!
>
> Jim
Hi:
First thing to try...apply a little tension to the RA lock. Maybe about
halfway, and see if the scope moves when you turn the knob. Basically,
though, with the RA lock unlocked the scope should move in RA when you
turn the slow-motion control (with the RA lock unlocked, does the knob
spin when you move the scope by hand?). When the dec lock is _locked_
you should be able to use the dec slow-motion. It's certainly quite
possible something is messed up inside the drivebase of this little,
old warhorse, however. ;-)
Peace,
Rod Mollise
Author of:
Choosing and Using a Schmidt Cassegrain Telescope
and
The Urban Astronomer's Guide
<http://skywatch.brainiac.com/astroland >
The Annual SCT User Imaging Contest is Underway!
<http://www.rothritter.com/contest/2006/ >
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Date: 21 Jul 2006 21:19:47
From: jim_s
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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ISSUE RESOLVED - mechanical problem.
For anyone who might have this same symptom...
The RA rotation mechanism relies on a small spur gear attached to the
auto-tracking stepper motor to act as a fixed point on the base, by
which the RA knob can rotate the fork around the RA pivot/axis centered
on the base. This same spur gear, of course, also drives the fork for
auto-tracking - the design relies on the fact that there is a gear
train attached to the stepper, making it virtually impossible to
reverse-spin the stepper.
The pinion gear was slipping on the stepper motor shaft when even
moderate torque was applied to it, so the whole RA gear/mechanism was
turning inside the base when the knob was turned instead of the fork
turning wrt the base (because there was nothing 'fixed' to the base for
the mechanism to turn against.)
I pulled the spur gear, cleaned it and the shaft, roughed up the shaft
a bit with a file, scored the inside of the spur gear with a small
steel rod and reset the spur gear on the shaft with a little bit of
Lite for good measure. (It was a bit of a struggle to get the gear
back on the shaft w/ the roughing up, so the Lite was probably not
even needed, but the gear is brass, so could possibly start slipping
again with more use.)
Basic procedure was:
1 - pull plastic cap from center of fork base
2 - remove socket head cap screw from center of base
3 - coax the fork/scope from the base with gentle rotation and some
gentle side-to-side rocking of the fork
4 - confirm the spur is turning on the shaft (in my case, I could turn
it with my fingers, so it was pretty obvious)
5 - pull the spur, noting the spur's depth on the shaft
6 - clean the shaft and the interior of the spur
7 - lightly roughen the shaft and the interior of the spur
8 - sparingly apply Lite to the shaft and gently horse the spur gear
back onto the shaft to the same depth it was before removal (if the
spur slips easily back on, more roughing is probably needed)
9 - clean up any excess Lite and reassemble in reverse order
Hard to imagine that others haven't had this problem given that the
spur gear is brass and that these scopes are getting old and well used,
but maybe this one was forced at some point or was expected to drive
the scope w/ a camera hanging off the back end or something.
Hope this helps someone if the need arises!
Thanks for everyone's help/suggestions.
Jim
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Date: 24 Jul 2006 09:20:37
From: bob
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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Your breakdown procedure sounds awfully familiar!
I'm so glad you resovled the problem. It's a simple, trusty little scope,
and it's hard to beat for portability as well. You'll have a lot of fun with
it.
--
Bob
Travel and Astronomy Photos
http://www3.sympatico.ca/bomo
"jim_s" <jim_stoll@yahoo.com > wrote in message
news:1153541987.520480.92130@s13g2000cwa.googlegroups.com...
> ISSUE RESOLVED - mechanical problem.
>
> For anyone who might have this same symptom...
>
> The RA rotation mechanism relies on a small spur gear attached to the
> auto-tracking stepper motor to act as a fixed point on the base, by
> which the RA knob can rotate the fork around the RA pivot/axis centered
> on the base. This same spur gear, of course, also drives the fork for
> auto-tracking - the design relies on the fact that there is a gear
> train attached to the stepper, making it virtually impossible to
> reverse-spin the stepper.
>
> The pinion gear was slipping on the stepper motor shaft when even
> moderate torque was applied to it, so the whole RA gear/mechanism was
> turning inside the base when the knob was turned instead of the fork
> turning wrt the base (because there was nothing 'fixed' to the base for
> the mechanism to turn against.)
>
> I pulled the spur gear, cleaned it and the shaft, roughed up the shaft
> a bit with a file, scored the inside of the spur gear with a small
> steel rod and reset the spur gear on the shaft with a little bit of
> Lite for good measure. (It was a bit of a struggle to get the gear
> back on the shaft w/ the roughing up, so the Lite was probably not
> even needed, but the gear is brass, so could possibly start slipping
> again with more use.)
>
> Basic procedure was:
>
> 1 - pull plastic cap from center of fork base
> 2 - remove socket head cap screw from center of base
> 3 - coax the fork/scope from the base with gentle rotation and some
> gentle side-to-side rocking of the fork
> 4 - confirm the spur is turning on the shaft (in my case, I could turn
> it with my fingers, so it was pretty obvious)
> 5 - pull the spur, noting the spur's depth on the shaft
> 6 - clean the shaft and the interior of the spur
> 7 - lightly roughen the shaft and the interior of the spur
> 8 - sparingly apply Lite to the shaft and gently horse the spur gear
> back onto the shaft to the same depth it was before removal (if the
> spur slips easily back on, more roughing is probably needed)
> 9 - clean up any excess Lite and reassemble in reverse order
>
> Hard to imagine that others haven't had this problem given that the
> spur gear is brass and that these scopes are getting old and well used,
> but maybe this one was forced at some point or was expected to drive
> the scope w/ a camera hanging off the back end or something.
>
> Hope this helps someone if the need arises!
>
> Thanks for everyone's help/suggestions.
>
> Jim
>
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Date: 21 Jul 2006 10:09:11
From:
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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Bob - I'm pretty sure its not related to the leg screws, as I can
duplicate the situation by applying just a bit of resitance to the fork
unit w/ my fingers (ie, when the scope is sitting flat on the table w/o
the legs), but I'll definitely try to rule that in/out as a possibility
this evening.
So you have no specific recollection of removing the fork assy from the
base and having RA parts springing out across the room or such? (I'm
guessing such an event would leave some impression on the memory! :-)
That's my main concern - making sure that I can reasonably expect to
get all the parts back in their proper place to put it back together
once its apart. I'm guessing that there must be something mechanical
going wrong in there, as twisting the RA knob surely shouldn't be
spinning the RA disk and not turning the fork...
Aside from this RA knob issue, I'm real happy thus far w/ the 2045
(albeit after only 1 hour of use) - its remarkably clear and rock-solid
stable (no plastic, lots of metal) The only down-side is that I spent
the evening sitting/laying on the ground last night, and had to just
about lay down prone to line things up through the finder, but I'll
drag a table or such out w/ me next time.
As an aside, the scope had been advertised as a 2045D, but the
nameplate on the base just says 2045. But, I'd also heard that the
original 2045's had some plastic parts while the 2045D's were all metal
- this one is definitely all metal. Anyone know if this is actually a
'D' or not? (its a dark blue tube and finder, w/ all else being black
metal). Also, incidentally, the 'Meade' name is upside down on the
tube - it looks as though someone had disassembled it at one point and
maybe got the tube reassembled while rotated 180 deg off. The finder
scope, focus knob, etc are all in the proper place (ie, the back is on
in the proper orientation.
Anyway, appreciate the suggestion - I'll double-check that tonight!
Jim
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Date: 21 Jul 2006 13:24:51
From: bob
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
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<jims.65311@gmail.com > wrote in message
news:1153501751.539305.23850@75g2000cwc.googlegroups.com...
>
> So you have no specific recollection of removing the fork assy from the
> base and having RA parts springing out across the room or such? (I'm
> guessing such an event would leave some impression on the memory! :-)
Oh wait a second...now that you mention it....
I seem to recall it came apart and went together with loss of either life or
springs. It may be possible that it was taken apart by the previous owner
and not put back together correctly. Maybe a they had a washer or bushing
left over. If you tilt it and have this problem, I'm guessing the angled
weight of the fork and tube is causing it to bind at the ring. Taking it
apart and examining the fit of everything might be a good first step.
--
Bob
Travel and Astronomy Photos
http://www3.sympatico.ca/bomo
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Date: 22 Jul 2006 20:33:09
From: jim_s
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
|
Yeah, that's pretty awesome! :-) I'd seen that previously - I actually
took a good long look at it to see if I could learn anything about the
RA mechanism from it. Based on the CT scan, the mechanism looked too
simple, so I figured I must be missing something, but after taking it
apart, it was actually showing me the right stuff, I just didn't
believe/interpret it as I should have! :-)
Man, if I had access to a CT scanner, I'd spend a whole lot of time
sending all kinds of fun stuff through there!!
Jim
bob wrote:
> This won't answer your questions, but it sure is cool.
>
> http://www.cloudynights.com/documents/ctscan.pdf
>
> --
> Bob
>
> Travel and Astronomy Photos
> http://www3.sympatico.ca/bomo
>
>
> <jim_stoll@yahoo.com> wrote in message
> news:1153456046.847385.141700@s13g2000cwa.googlegroups.com...
> > I've just acquired a Meade 2045 and seem to be having problems w/ the
> > Right Ascension Slow-Motion control (or I'm just clueless - a distinct
> > possibility at this stage)
> >
> > When the scope base is sitting flat on a table (ie, mini tripod legs
> > not attached), w/ the RA lock in the unlocked position, I turn the RA
> > slow-mo control and the fork assembly turns on the base, w/ the RA ring
> > remaining stationary wrt the base. When I attach the tripod legs, w/
> > the fork/scope now at an angle to the table, I turn the RA slow-mo
> > control and the RA ring turns, but the scope and base remain stationary
> > - the RA slow-mo control doesn't seem to have the 'grip' to actually
> > turn the scope when the weight is not directly centered over the RA
> > axis.
> >
> > So, is this something broken or needing adjustment, or am I not
> > understanding the purpose of the RA slow-mo control? (I thought that I
> > should be able to use that to search a small area of sky through right
> > ascension, vs manually grab and position the fork wrt the base - that
> > can't possibly be the way its done...)
> >
> > Thanks for any assistance!
> >
> > Jim
> >
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Date: 22 Jul 2006 11:58:41
From: bob
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
|
This won't answer your questions, but it sure is cool.
http://www.cloudynights.com/documents/ctscan.pdf
--
Bob
Travel and Astronomy Photos
http://www3.sympatico.ca/bomo
<jim_stoll@yahoo.com > wrote in message
news:1153456046.847385.141700@s13g2000cwa.googlegroups.com...
> I've just acquired a Meade 2045 and seem to be having problems w/ the
> Right Ascension Slow-Motion control (or I'm just clueless - a distinct
> possibility at this stage)
>
> When the scope base is sitting flat on a table (ie, mini tripod legs
> not attached), w/ the RA lock in the unlocked position, I turn the RA
> slow-mo control and the fork assembly turns on the base, w/ the RA ring
> remaining stationary wrt the base. When I attach the tripod legs, w/
> the fork/scope now at an angle to the table, I turn the RA slow-mo
> control and the RA ring turns, but the scope and base remain stationary
> - the RA slow-mo control doesn't seem to have the 'grip' to actually
> turn the scope when the weight is not directly centered over the RA
> axis.
>
> So, is this something broken or needing adjustment, or am I not
> understanding the purpose of the RA slow-mo control? (I thought that I
> should be able to use that to search a small area of sky through right
> ascension, vs manually grab and position the fork wrt the base - that
> can't possibly be the way its done...)
>
> Thanks for any assistance!
>
> Jim
>
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Date: 24 Jul 2006 09:42:17
From:
Subject: Re: New Meade 2045 user - basic knowledge issue or mechanical problem?
|
Yeah, I'm loving it already - I just grab it and run out in the front
or back yard when I have 15-20 min w/ some clear skies, and I'm
observing the entire time - no fuss, no muss! :-) I can definitely see
where something larger would be nicer, but the simplicity and
portability just can't be beat!
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