Meade Equatorial Wedge for LX-90

On Mon, 20 Sep 2004 17:47:44 GMT, "Grimble Gromble"
wrote:


When I first arrived at this newsgroup I asked if anyone would be interested
in equatorial wedges designed for a single latitude (to be specified by the
person ordering the wedge). There was no response. I'll reiterate it here
just in case there is any interest.

The reason for taking this approach is that this would allow the company I
work for to machine a couple of plates: one for mounting the telescope, one
for fitting to the tripod - or other horizontal surface. These plates would
then be angled by a couple of spacers which would be determined by the
latitude at which the telescope is used. I'm interested in one for the LX90
because that is the telescope I have and I will be making such a wedge in
due course. If you observe from more than one latitude, you'd simply need
another pair of spacers. This helps reduce costs significantly, and would
also make the wedge rather more rigid as the plates would be bolted to the
spacers. Aligning with North shouldn't be a problem.

If there were sufficient interest, we could make a range of plates for
telescopes, and a range of plates for the tripods - or other horizontal
surface. Mix and match!

As mentioned before, I have little idea what the cost would be (although
material costs are quite small at around £30 - £40 for plates and spacers),
but we make jigs and similar items for our customers at rather less than
£150. We also have anodising facilities so making the parts out of
aluminium would allow us to anodise the surface (a hardening process) and
colour them black.

Anyone?
Grim


Yep, I'd be interetsed, depending on price, of course.
- Mike
N 50 deg 46 min 49 sec

"Colin Dawson" wrote in message
...
"Grimble Gromble" wrote in message
...
[snipped a lot]
When I first arrived at this newsgroup I asked if anyone would be
interested in equatorial wedges designed for a single latitude (to be
specified by the person ordering the wedge).
This sounds to me like something that could potentially go down well with
the dome builders. The whole point there is to setup the scope so that
it's perfectly aligned, and solid. You would still need to be able to
adjust the wedge enough to line everything up perfectly. But you're right
that you don't really need 45° of travel. If I ever build an observatory,
I might get a different wedge, so that I can keep my scope portable.

My thought was that the wedge would be mounted on something that had already
been set horizontal (even in the case of a tripod). After all, it shouldn't
be difficult to get a horizontal - unless you're sited next to a large
mountain.
Grim

"Pete Lawrence" wrote in message
...
Possible interest registered. I'd be looking for a sturdy option for
a 10" LX200. As of yet, the scope hasn't shown me anything that
justifies the ridiculous price of the official SuperWedge.

Also noted. I'll see what I can do.
Grim

"Chris Taylor" wrote in message
...
(Irrelevant content snipped)
I'd love to take advantage of your offer. I do remember the post and had
no need for it at the time owing to shorter exposure requirements of the
LPI.
My Latitude is N51deg (and 14 Sec if that matters?).

Noted. I hope no-one has any deadlines.
Grim

"Mike Murphy" wrote in message
news
Yep, I'd be interetsed, depending on price, of course.
- Mike
N 50 deg 46 min 49 sec

Will let you know (eventually). Got some actual design work to do first
(mainly for the plates for the scopes and tripods).
Grim

"Grimble Gromble" wrote in message
...
"Chris Taylor" wrote in message
...
(Irrelevant content snipped)
I'd love to take advantage of your offer. I do remember the post and had
no need for it at the time owing to shorter exposure requirements of the
LPI.
My Latitude is N51deg (and 14 Sec if that matters?).

Noted. I hope no-one has any deadlines.
Grim


Hi Grim

No imminent deadlines. I was looking to put this off until a visit to the US
around Xmas anyway.

Regards


Chris

"Grimble Gromble" wrote in message
...
"Colin Dawson" wrote in message
...
"Grimble Gromble" wrote in message
...
[snipped a lot]
When I first arrived at this newsgroup I asked if anyone would be
interested in equatorial wedges designed for a single latitude (to be
specified by the person ordering the wedge).
This sounds to me like something that could potentially go down well with
the dome builders. The whole point there is to setup the scope so that
it's perfectly aligned, and solid. You would still need to be able to
adjust the wedge enough to line everything up perfectly. But you're
right that you don't really need 45° of travel. If I ever build an
observatory, I might get a different wedge, so that I can keep my scope
portable.

My thought was that the wedge would be mounted on something that had
already been set horizontal (even in the case of a tripod). After all, it
shouldn't be difficult to get a horizontal - unless you're sited next to a
large mountain.
Grim


The problem with a fixed latitude wedge is that it's not as portable. The
problem is that you need to set the scope so that the Azimuth adjustment is
pefectly aligned with the Equator. Without any means to fine tune the
wedge, it'll be pretty useless. The way that I use my scope at the moment,
there are several sites that I use. Setting up the scope pefectly at one
site, is not the same as a site a few miles down the road. I need to fine
tune the scope each time so that it's tracks correctly. If the only way
to adjust the Latitude, is via a spacer, it becomes a nightmare when working
in the field. Especially if the only way to add/remove a spacer is by
dismantling the scope. With my wedge, it's a simple case of turning that
knob.

Regards

Colin Dawson
www.cjdawson.com

"Colin Dawson" wrote in message
...
[snipped a lot]
The problem with a fixed latitude wedge is that it's not as portable. The
problem is that you need to set the scope so that the Azimuth adjustment
is pefectly aligned with the Equator. Without any means to fine tune the
wedge, it'll be pretty useless. The way that I use my scope at the
moment, there are several sites that I use. Setting up the scope pefectly
at one site, is not the same as a site a few miles down the road. I
need to fine tune the scope each time so that it's tracks correctly. If
the only way to adjust the Latitude, is via a spacer, it becomes a
nightmare when working in the field. Especially if the only way to
add/remove a spacer is by dismantling the scope. With my wedge, it's a
simple case of turning that knob.

Many thanks for your comments, Colin. The wedge I mean to build for myself
is not intended to be portable. I haven't gone into any details as yet,
however there are clearly 2 aspects to getting the plane of the wedge
parallel to the plane of the equator. Only one of them is the latitude. It
is also necessary to align the wedge with true north (I believe true north
is the direction towards the intersection of the earth's rotational axis
with the surface of the northern hemisphere of the earth?). The pole star is
often used as a rough guide, but I suspect we can do better than that.
Similarly with levelling the base for the wedge. In principle one could
provide a transparent template marking the positions of polar stars (either
in rings, or as points capable of rotating about the polar axis) to serve as
an alignment aid for setting up. I'd rather keep it as simple as possible -
the point being to save lots of money; do you have lots to spare?

There is no obvious reason I can think of (if one is not using a tripod) why
the base of the wedge could not be fitted with between one and three
adjusting screws if such proves to be necessary. We'll see.

In the meantime, if you have any show stoppers, please air them.
Grim

On Wed, 22 Sep 2004 19:42:43 +0000 (UTC), "Colin Dawson"
wrote:

If the only way
to adjust the Latitude, is via a spacer, it becomes a nightmare when working
in the field. Especially if the only way to add/remove a spacer is by
dismantling the scope. With my wedge, it's a simple case of turning that
knob.

I'm told that small changes in latitude can be accommodated by using
the tripod leg height adjustment.
- Mike

On Wed, 22 Sep 2004 00:03:51 GMT, "Grimble Gromble"
wrote:

"Pete Lawrence" wrote in message
.. .
Possible interest registered. I'd be looking for a sturdy option for
a 10" LX200. As of yet, the scope hasn't shown me anything that
justifies the ridiculous price of the official SuperWedge.

Also noted. I'll see what I can do.
Grim

I've now managed to get a solution for what I consider to be a
reasonable price. Thanks for looking into it anyway.

--
Pete Lawrence
http://www.pbl33.co.uk
Most recent images http://www.pbl33.fast24.co.uk/recent_images.html