3 replies to this topic

[seanmartin]

hi

I hope I am in the right spot

I just got an astroscan telescope at the flea market and am having some trouble

I gently cleaned the front glass and the one eye piece that came with it( 28mm)

when I train it on and object of a distance of a couple hundred feet it will focus sharp

but when I tried to look at the moon it would not focus sharp, it would appear to start to focus but then as I would continue it got worse again

I did some googlin and see that there may be something going on with the big mirror positioning, relating to some foam backing breaking down

but I am not sure if this is a symptom or not

any sage advice and or direction would be greatly appreciated.

seanmartin

[ShaulaB]

Is the eyepiece holder slipping down? Can you get it focused on the Moon, then it goes out of focus? That's a common problem that can be fixed.

 

The 28 mm Edmunds RKE eyepiece is one of my favorites. It is the opposite of the new-fangled "porthole in space" designs.

[HagglePig420]

If it's an old Astroscan, it almost certainly needs to be collimated... or the foam that supports the primary needs to be replaced...

[seanmartin]

Thanks for the reply

It did indeed need some work

I did some fishing around for info and found a good thread on breathing new life into the can

The eyepiece holder was firmed up with a piece of electrical tape applied vertically on the holder where it makes contact with the shaft (it would be nice to replace the rubber hose though).   any ideas?

I removed all the glass and cleaned them with some solution I use for cleaning my records and it worked great

The foam backing was in sad shape as was foretold 

I got some thin packing material, the white closed cell stuff, and cut three concentric pieces starting at about an inch and a half and up to three and a half

instead of using one thicker piece. This would sit nicer in the curve of the can

As far as the snap ring installation I made a little holder out of a hacksaw blade. It basically holds the spring together so you can just get it where you want it and then release it. It made a nice holder when you have to reach down into the scope for the primary mirror

I tried it out on the moon and it focused nicely. I have since ordered a peep hole finder and a barlow x3 to see how that works

I think it will be a nice camping scope