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Hi Gary Yes I used a buiscuit cutter and a bench drill at the slowest speed. It took me about 1.5 hours to cut it. It wasn't that hard just patience. Mind you I did practise by cutting 5 holes on 6mm plate glass before I summoned the courage to cut the real hole. The mirror was not figured but it was polished and spherical. It was an F6 ( One of the things I found difficult so far has been what kind of compromise to make on the telescope. A cass has so many more variables than a newtonian and finding the compromise that fitted me was difficult but fun). I started to regrind it but I had to make a new tool as the other one was worn out. one mistake I made was not making the tool the shape of the mirror so I have to rough grind a lot more. I also took a piece out the side by being in too much of a hurry but luckily it will be hidden by the arms that hold the mirror to the cell. On figuring the secondary I'll let you know how I do it but first I'll get the primary done. The way I was taught to make the pitch lap was to make a dam around a plaster tool, pour the pitch in put a grid that finish in a V (I use an old laundry basket), put the mirror on top of the grid press hard with your body weight, pull it all out and there you go. The grid is covered in dishwashing liquid first. The mirror is warmed up and covered in dishwashing liquid as well. one of the disadvantages with this though is that if you are not very carefull you may end up with scratches on your polished mirror. I can't wait till you do the star test to see how you go and to see the finished telescope. well done. Good weblink too.
Regards Cristian
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