ETX TECHNICAL TIPS Last updated: 16 August 2004

Eye Piece End Cap for LXD55 AR5 5-in

Sent:	Monday, August 16, 2004 12:50:16
From:	dawson.michelle@tiscali.co.uk
First off, Hello from Yorkshire, England and second hope the three
pictures in the attachmant I have sent do not take up much time and
space at your end, if I have caused any problems, you have my apologies.
Right down to business, hope the following text is clear and that it
comes over, please could you add it to your website as a contribution,
hope it is of some use!!!


Eye Piece End Cap for Meade LXD55 AR-5 5-inch refractor.

Although I specifiy this item for the Meade 5-in refractor, it would be
of use to any closed optic telescope. When I received my 5-inch I was a
little disappointed at the cheapo/plastic end cap for the focussor, if
the thumb screw was too tight there was a possibility of deforming it,
some thing better was in the offing!!!

Having access to a lathe, I turned a rod of aluminium 42mm in diameter
and 52mm from the chuck jaws. Followed up with a internal bore 25mm in
dia. and to a depth of 30mm. The 1.25-in diameter was turned to a length
of 26mm. The remaining 42 mm diameter was diamond knurled and chamfered
at 45 deg. After parting off, the piece was rechucked on the 1.25-in
diameter and was faced  to match the pattern on the focussing knobs.

Next, a 24.9mm diameter ring, with internal diameter of 21 mm and a
thickness of 5mm was turned. To this on one side a round piece of
stainless steel mesh was affixed with two-part epoxy. While this cured,
3 x M3 diameter holes were drilled and tapped 4 mm from the open end of
the main piece and equi-spaced, these are to take M3x3 slotted  grub
screws, these purchase on to the ring.

Paint or have anodised to taste, I left mine in the shiny as is natural
aluminium, if I drop it in the dark it should be seen easily!!! Pack
with a silica-gel pack which is retained (Obviously) with the mesh/ring.
So, when you pack away your pride and joy, this addition will, keep the
damp out, the mice and bugs!!! and hopefully look good.

If you do not have a lathe, join a night class or school, check your
local yellow pages directory or failing that get the local astronomical
society engineer to make you one. If you have never worked on a lathe
this is also a good easy first project. I have not provided a drawing,
as such a simple piece should make up easily, the only critical diameter
is the 1.25-in, which obviously is the diameter of the eyepices! the
other sizes are not critical, but the bore ring interface should be a
good fit for neatness.

Please refer to my pictures and have fun!!!







Mr. Weasner, hope you followed that, please edit to your taste and if
you don't like metric sizes, let me know and I'll convert for you
Americans!!! Also trim the pictures to your own taste, looking forward
to seeing it on the www!!!

Martin Dawson.

P.S. Excellent web site, will visit again and again, keep up the good
work!!!

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