My homemade 488mm (19") F4.85 Dobsonian
Posted 10 November 2012 - 08:15 AM
I'm an amateur telescope maker from Finland (currently studying in Germany). Recently I have finished my latest half a metre Dobsonian and I was thinking of shearing the story with you. Actually I finished the telescope already a year ago but I finally had some time to translate my home page from Finnish to English.
488mm F4.85 Dobsonian Telescope
Posted 10 November 2012 - 08:30 AM
Posted 10 November 2012 - 08:42 AM
Posted 10 November 2012 - 10:01 AM
Posted 10 November 2012 - 11:45 AM
Posted 10 November 2012 - 10:16 PM
Posted 11 November 2012 - 02:57 AM
Posted 11 November 2012 - 04:11 AM
You look fairly young so I am glad im not the only mirror grinder in their 20s.
Yes, indeed! I was only 20 when I started the project freshly after completing my high school.
I would like to point out here that many people are afraid to make big mirrors. I believe that people grinding 25-30cm size mirrors are very well capable to make half a metre mirros if they just have enough motivation and patience for it.
This mirror was only fourth I have finished after completing 150mm, 300mm and 75mm mirrors. The step from 300mm to 488mm was big but in the end I think this half a metre mirror was not significantly more difficult to grind as my 30cm mirror. It just took some more time.
So for grinders thinking whether they should or should not start grinding a large mirror I would just say GO FOR IT!
Posted 13 November 2012 - 09:44 PM
Posted 14 November 2012 - 01:37 AM
Yes, around 370 hours including time for tool making etc. For comparison it took me 300 hours to make the 300mm (12") mirror. The difference is not that big because I got lot of experience while doing the 300mm mirror.
it took nearly 400 hours to complete this mirror?
Posted 14 November 2012 - 02:38 AM
How well do you like the CF spider vanes?
Posted 14 November 2012 - 03:36 AM
Posted 19 November 2012 - 06:24 PM