Guest mark59 Posted February 7, 2013 Share Posted February 7, 2013 Hi I'm new to astronomy & have just inherited a prinz 440 telescope. My very first telescope! But on inspection, I have found a brown blemish in the centre of the lens at the front. It is made up of 2 lens stuck together & the blemish sandwiched between the 2 lenses. Can anyone advise me what to do? many thanks mark Link to comment Share on other sites More sharing options...
Teslar Posted February 7, 2013 Share Posted February 7, 2013 (edited) Sounds like mould. I'm not too familure with these though I heard they were sold by dixons in the 70's so it probably quite old. It may be possible to strip it down and clean the lenses but you'd have to be extremely careful and read up on the best method and materials for cleaning them. Most likely Baader cleaning fluid and Baader cloth would do the job but do not use anything else at the risk of doing more damage. Also mark the outside of the tube and the edge of each lens to try and ensure you get the same alignment when you re assemble. I've never had one if these in bits so can't advise you on the detail. But sounds like its your only hope of resurrecting this scope and hope that any coatings to the lenses is unaffected from what I've heard tube should be marked with circle T or circle K I believe the T were the better lenses. When I was a lot younger a friend had one of these Edited February 8, 2013 by Teslar Link to comment Share on other sites More sharing options...
Guest mark59 Posted February 7, 2013 Share Posted February 7, 2013 Hi Tom Thanks for your reply. There is no obvious way in which the lenses can be separated, the blemish is between the lenses. I've read that gum arabic is/used to be used to stick lenses together? mark Link to comment Share on other sites More sharing options...
Daz Type-R Posted February 7, 2013 Share Posted February 7, 2013 Hi Tom Thanks for your reply. There is no obvious way in which the lenses can be separated, the blemish is between the lenses. I've read that gum arabic is/used to be used to stick lenses together? mark Pherhaps take it to the next Wymeswold meeting for somebody to have a look at, somebody may be able to help? Link to comment Share on other sites More sharing options...
philjay Posted February 7, 2013 Share Posted February 7, 2013 Hi Mark and welcome to the forum Sorry to hear your having problems with your trusty 440. Hope you dont mind but a few questions before I can help, (I own and have owned many antique/classic and vintage scopes and pulled many apart but never played with a 440. Astral and 660 yes but 440 no. How do you know they are stuck together have you had the lens out? If not If my memory serves me is the 440 a 60mm? When you look in the front of the objective lens (front lens) can you see 3 silver tabs equispaced around the outside of the objective? Is the objective cell (front lens holder) plastic or metal ? Is the dew shield ( the cylinder attached to the front of the objective lens cell) plastic and removeable? If when you remove it (either pull or unscrew is there a retaining ring visible for the objective. Cheers Phil Link to comment Share on other sites More sharing options...
Guest mark59 Posted February 8, 2013 Share Posted February 8, 2013 Hi Phil Thanks, yes it says D60mm F710mm (wotever that means!). The dew shield is metal & unscrews, then a plastic retaining ring unscrews to allow removal of lens. The lens has 3 equidistant silver tabs as you describe, then a slightly thinner 'lens' on top, no lens cover as I would describe. Both of glass. Where will I find details of the wymeswold meeting? thanks mark Link to comment Share on other sites More sharing options...
Brantuk Posted February 8, 2013 Share Posted February 8, 2013 Watch the Info and Announcements section (EMS Meets board) for meetings. They can be arranged (or cancelled) at very short notice. It all depends on the weather on the day. Directions will be posted in the meeting thread - or you can take a sneak peek at prior meetings threads if you'd like an early heads up on directions. Link to comment Share on other sites More sharing options...
philjay Posted February 8, 2013 Share Posted February 8, 2013 Hi Mark The lenses are air spaced, the foil tabs keep the gap correct. The lenses on the 40mm scopes were cemented but the 60mm were not. So if you undo the retaining ring and carefully take the lens out you will find they arent glued. If they are stuck then that may be as a result of the mould in between. Take care when dismantling the lens to ensure they go back the same way, put 2 pencil lines down the edges to help orientate them. Do not loose the foil spacers and ensure they go back the same. I use ordinary camera lens cleaning fluid and cloths to clean my lenses and this has worked well over the years. If the mould doesnt come off easily do not scrub,take your time. Scrubbing may damage coatings Hope that helps Link to comment Share on other sites More sharing options...
Guest mark59 Posted February 9, 2013 Share Posted February 9, 2013 Phil, Thank you so much, I took courage in both hands & carefully took a blade to separate the lenses. Pop! they came cleanly apart. Cleaned up beautifully, thank you again Just waiting for a clear night now! mark Link to comment Share on other sites More sharing options...
Craig Posted February 9, 2013 Share Posted February 9, 2013 Phil - you never cease to amaze. Welcome to the forums Mark, hope to see you at a meet with that nice clean scope of yours! Link to comment Share on other sites More sharing options...
philjay Posted February 10, 2013 Share Posted February 10, 2013 Great stuff Mark. Hope to see you with teh scope at a meet if ever we get a clear night again Link to comment Share on other sites More sharing options...
Rusty Strings Posted February 10, 2013 Share Posted February 10, 2013 My first proper astro refractor was a prinz 330, wish I still had it . Glad yours will fight again Mark. Link to comment Share on other sites More sharing options...
Guest Nigel Posted March 8, 2013 Share Posted March 8, 2013 Hello I'm still using a prinz 330 that I've had since new bought for me in 1972 by mi dad works really well I've even still got the box ,clear night and it's out in the garden with it Link to comment Share on other sites More sharing options...
Brantuk Posted March 8, 2013 Share Posted March 8, 2013 Hi Nigel - good to have you on board EMS If you pop up an intro thread in the "Welcome Section" it'll give everyone chance to welcome you to the forum. Link to comment Share on other sites More sharing options...
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