aperture fever hits us all at sometime.it has now hit me 3 times.8" was big enough for 6 months.12" was big enough for 6 months and now 16" was big enough for 6 months.where next?there's no commercially available scopes bigger than 16" in the uk and to buy one from the usa or a custom uk builder would have cost £7000-10000 for the size I was after so a plan was hatched to build something.

myself and damian(master) attended a mirror making seminar with john Nichol who took away some of the myths of mirror making and made it seem much less of a dark art.we came away from the seminar with a real hunger to make one ourselves.originally I had planned to make a 16" to fit in my current scope but when I got the prices and found out it was only about £100 more expensive to get a 22" over a 16" I couldn't resist.

im sure a few of you will think im totally mental to just dive into a project this big and I would be inclined to agree with you as the only grinding ive done is to hog out a 12" blank to f5 so im still very much a novice but im prepared to take it steady and take my time and ask for help when needed.

about 2 weeks ago I took delivery of a 22" low expansion blank :) :) :)

actually I lie,i bought two but one is for my friend damian.we are both building a 22" scope so will be able to help each other on the way.

a 70kg pallet applies(2x22" mirrors)

a 22" low expansion blank!!(22kg!!!!!)

compared to a 12" blank!!

damian admiring one of the tables he made for our builds!!!

set up in the greenhouse out of the way

so I started with the blank just over a week ago and have just been taking it steady.i did make mistakes during the bevelling stage by using the least abrasive side so it took me about 6 hours to bevel both sides and I snapped on stone through stupidity(I tried banging dust off it) and the second ended up like this

safety first

yesterday I started grinding the back of the mirror flat but its not uniform and has a raised section across the centre which ive highlighted in this photo

currently grinding this out with short chordal strokes and will then use w strokes to get it back uniform after I have got the centre back towards the same level.im using up some old 60 grit I had left over from a 12" trial grind then be moving onto 80 grit which will take longer but theres no rush.

heres the back of the mirror after just over an hour of grinding.some of the edge waves are still visible but the centre is smooth so im definitely grinding the centre out more than the edge

big thanks to john as he has supplied lots of information and help to get me to this point and im sure I will require much more.

more updates as and when :)