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tonyh66

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About tonyh66

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    Star Forming

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  • Location
    Invernessish
  1. give it a go, some of those old Tasco's are good scopes, finding a replacement cog may be an interesting pastime though
  2. you can polar align EQ1 and 2 without a polarscope, its just a bit more difficult
  3. my first thought was missile guidance:confused:
  4. not a chance, unless you are an electronics expert and can build a new camera from the parts. Unless of course it all still works when put back together
  5. have you got a link, there is a bresser type bino going on sale here on 9th april.
  6. a quick spin around internet and a question on my art glass forum has yielded some interesting stuff, apparently it takes approx 28 hours to anneal 38mm thick glass add in a couple of hours to slump and fuse and you are looking at nearly 2 days kiln time. I remember the annealing program for windscreens ran for about 8-9 hours but the glass was nowhere near as thick. I also have been given a book reference to look at, apparently it has some detail about a telescope mirror in it. Will post the reference when im a bit more together and not at work
  7. This is true, the choices at the bottom of the market are: cheap chinese imports, like these and countless others on Ebay 2nd hand 70s/80s binos like Zeniths or Regents or one of those dodgy made up german brands, these are all either early chinese imports or reasonable quality japanese. If you want to shell out a little more try for a 2nd hand pair of Zeiss on Ebay. I think the quality of the imports are getting better, Strathspeys for example are getting decent reports in S@N magazine
  8. pretty daft to suggest a set of binos at nearly 10x more expensive than the original post especially as they are not 10x50s, the lidl binos are normally rebadged Bressers and offer good value if you cannot afford to spend £110 on binos
  9. look like Bressers to me or the usual bresser rip offs
  10. Im trying to land a pair of cheap bins but im always reluctant to bid over £6
  11. Peter got there first, annealing can be built into the fusing and slumping program, as he says its just a case of holding the glass at a particular temperature to release the internal stresses before ramping the temperature down slowly to avoid re stressing the glass. You don't say what kind of kiln your going to use but you really need to control temperture, ramp and dwell times accurately. with regards the moulds, it was over 7 years ago since I left the glass forming job so its a bit fuzzy. As I remember the stuff we used was silica cement, a quick recce of the internet found that a 50/50 of silica and plaster has been used to make mirror moulds and there is an interesting piece out there where the mirror has been formed with a 'waffle' back to make it lighter. I will knock up a couple of sketches and description of detail when I have finished this set of night shifts im working at the minute. i will also throw out the question of fusing and slumping 38mm thick glass on the art glass forum I frequent to see if they can come up with a rough kiln program.
  12. I used to slump glass for bullet resistant windscreens, the moulds used for those were made from steel section - not a super accurate way of doing it, but it worked and was cheap. The other stuff i used to do was laminated glass for CRTs and radar screens and the like. the moulds were made from a high silica cement which were made using wooden formwork. Basically if your wooden formwork(mould) was accurate then the mould for bending the glass would be accurate. Bending/forming the glass in the kiln was the real dark art, you just have to make sure you get no gas trapped between your layers which creates bubbles, forming gas vents into the mould helps.
  13. don't suppose you fancy doing me a 20inch blank in your kiln? Have you thought of slumping the glass to somewhere near the correct parabola to reduce the grinding/polishing? i used to work in glass and know how to make moulds to do this.
  14. I think i was bidding against you :~)
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