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Cheers John I've yet to start the build of mine but it'll be on it's way soon

Thank you everyone for the encouragement and kind words.Ron, I have looked at Mel's page a few time's it's amazing the amount of literature you read when you get into all this. A lot quote Texereau as the be all and end all of mirror making.It's not the case just another way to do it. It's all helpful especially the encouragement and interest of others on here. I have found a few site's on mirror making and logs of people's battle's with mirrors. I have had many a battle with enthusiasm and have my occasional low points but always end up at the same conclusion that time and effort will sort it out.I just sometimes can't see the wood for the trees More work possibly tomorrow but definitely on Friday and the weekend. Cath as Peter say's I'm working towards a sphere then I can start the exciting (in mirror making) bit of parabolising Damian

Battle has continued over yesterday and today so another 3 hour's of the turned edge. Here's the outcome Inside ROC Silly me I had a cup of coffee stood not too far away in the image so there's a little thermal distortion on the lower side of the middle right hand band Outside ROC I'm not too sure there has been much change so may have to think about different tactics? I plan on another 3 hour's and see what things are like then? Damian

I'm looking forward to that too and like the rest it will probably be a fight all the way! More work on the turned edge today Damian

Managed an hour through the day but it's time for work. I'll carry on tomorrow with a test first thing to see if things have changed then probably another couple of hours of going round in circles as that's what mirror making is all about Damian

I'll agree fella as were well into our second year of this! Hope the channels are now cut

Thanks Nigel, I'm going to carry on with the stroke I'm doing at present and hopefully the edge will behave itself soon? although that maybe another 10 hour's work or so? I shall then make a start on the central hill and hopefully onto a sphere. I will consult John on the way to go about the next stage although a sphere is my first goal. Damian

Thanks Rick it's been a battle of I think 17 hours up to now. I agree the diffraction make's it look far worse than it is and when you move closer to ROC with less lines it amplifies it even more. I'll put the focuser on the build thread when I finally get there so it all ties up with that. Making a few changes which I've been thinking about on the next build it all depend's how long the mirror take's. Damian

Today has been another 2 hours of edge work and I'm sure things are improving albeit at snail pace. More image's after the last session Inside ROC Outside ROC Was hoping for a bit more work than I managed today but as usual side tracked onto dad's car repairs. More work tomorrow all being well but I have my own car to sort out and wait in for the delivery of a lovely focuser for the scope build Damian

I've done it all by hand as I wanted a true reflection of what can be done with basic tooling. It's not gone too bad up to now

Hi Derek Yes I've seen the video's of Gordon definitely good to watch and it does show the work involved in making a large mirror. Only thing it doesn't portray is the time scale and mental strength you need to see it through to final conclusion. It's taken a lot and will take more before I'm finished. Done another 2 hours today although was hoping for more but had my dad's car to fix so cut short today. I'm still battling the turned edge and get to a sphere so I can actually start the figuring process of creating the parabola. Long way to go yet with the edge problem though. Damian

Result's of today's session Inside ROC Outside ROC Got to admit it's difficult to see any difference Tomorrow is another day with the new cerium oxide stock so I'll carry on with the polishing Damian

Cheers James. It really is testing at time's and I wouldn't be where I am without good support Damian

Cheers Guys,I've been trying to work the edge with the 10" lap starting at the edge and working inwards in a tight W as glass need's removing all over to bring the surface down to the bottom of the turned edge. I'm obviously working the edge more as you say the oblate centre proves this and can be dealt with later. It's beginning to show progress but as John said don't go mad. Looking forward to this aft and tomorrow to see how the image changes fingers crossed it will show more improvement. Damian

Morning all, I've steadily worked away at the mirror and here are the latest Ronchigrams. Roughly 12 hours since I started to work on the TDE Inside ROC Outside ROC I had a few speck's of moisture on the mirror centre from where the lap had been pressing on top in the image's . The turned edge is improving but I'm also getting a hill forming in the centre which will be dealt with once the edge is sorted. I was running low on Cerium Oxide (2.5uM) Wednesday so yet again .5Kg more ordered which hopefully will see me to the end but only time will tell. More work this afternoon Damian

Thanks for the image Ron hopefully I will one day see the same reflected back at me. At present it's a battle with the edge and then hopefully achieve a nice sphere. The battle is still raging and it will be quite a while until the war is won. I will be using a matched Ronchi test but this will be backed up hopefully in the end by the Ross Null test and then the final test by John on his test equipment. Long and winding road to travel as yet. Damian

After this mike I'm gonna have a few! Make sure I bring some up that there Galloway to celebrate

Just a couple of pic's of the 10" lap in action, I apologize for the blurry shots think the camera is as dizzy as I am after all this going around in circle's It's working well just an addition to the thread whilst pressing again Damian

Testing resumed today and I took the following images More work this morning although I have to go to work worst luck! Damian

Thank's for commenting Nigel I have tried a slightly different stroke on the second session and this has been a tight W as you say about an inch overhang working towards the centre with the lap overhanging the mirror about an inch at the end of each stroke. As I read it the glass needs removing across the entire mirror to bring it down to the edge without creating a deepened centre which will be difficult to correct as Ron say's . The edge seem's to be improving to me. I shall have another session before the day is out using the same stroke then leave leave it overnight to settle and take image's Damian

Cheers Mark although I wish that was true

Thank you for the advice Ron Yesterday I worked for the first time with the smaller lap for a total of 3 hour's through the day on the mirror cooling and testing between sessions. The surface to be honest hasn't changed that much at the edge but the middle now has a bump forming and overall the surface is rougher so to say Stoke yesterday was at an approximate 5" from the edge with very little overlap. More work today so as the mirror is cooling off I thought I'd add a bit to the thread. Damain

To be fair Paul I struggle with them, as you say more experienced eye's know what they are looking at. done a couple of hour's with the smaller lap today but I can say the mirror is now looking a little less smooth and I'm going to have to really study the image's to see if the edge is getting better. One thing I do know the middle now has a hill!

Thanks Nigel, good to have a second opinion and confirms what John said. I've just done ten minutes after an initial hour long wet press. The lap is not quite working so I have warmed it and I'm going to wet press again for an hour with weight on whilst moving it around to stop sticking. I've taken some test image's before I start so I can compare the progress later once the mirror has cooled. Damian

I forgot to add I also took some foucault images. I had the Knife edge on a slant as I attached it to the tester with blu tac. Think I must've had a big smudge on the mirror too? I took these on the 13/02 And these on the 21/02 Quite difficut to get decent image's and to interpretate as to what's going on but the first set show the edge quite well Damian