JRM

good to hear Rich, keep us posted.

Rick M

Wait till you see Saturn then you will"WOW" all over again Atb para

Agreed completely and then M42, totally awesome

 

 

I never tested my mirrors until they were fully polished. That way I avoided the temptation

 I totally agree,

 you only want a first look ( which I opted out of) to insure you have not ground a really bad zone in the

glass, testing glass before completely polished out only tend to make things worse, polish more worry

less Rich, for what its worth, that to me is not stig, its a zone on a glass that is not polished out as of yet.

can not post a photo of astigmatism here, will put one on my log,  polish on,once your sure she is done

and polished out then test, keep everything random and you should have no problems.

Rick M

lesson learned there eh Rich, some times it is the best way to learn, we never forget after that, trust me been

there, done that, usually move things every 30 minutes but have left it lots longer with mesh between for

micro faucetting, but 30 minutes is long enough for things to stick like no tomorrow. and as I said they are

not mistakes they are lessons learned,they make it easier the next time around... hopefully the scratch will

polish out, cheers my friend.

Rick M

thats a nice looking lap Rich,gotta hate when scratches happen but

might the scratch polish out well you polish or is it too deep for that.

nice to hear your back at it again.

Rick M

Best of luck then Rich,

it has been told to me by a gent of highest regards and much experience and wisdom,of whom has also made many many a mirrors over the years and still does these days that he has never seen a 20" mirror polished out in less than 15 hours and that mirror was polished out on a machine, so your 10 to 12 might be a tad low, but one can hope.

I did some 6 hours with pads and as optimistic as I was about the spead of polishing am figuring on at least 10

more hours of polishing with pitch,(forever the optimist)but likely more then that.

What are you using for pitch? I have 4-1/2 pounds of gugolz 64 for mine, power was out for a few days because of storm so I too shall soon make the pitch lap and get at it as well.

keep the reports coming.

Rick M

Looking real good Rich, easiest way to determine shape is to sharpy test first wet with new grit,it tells you

alot about how things are progressing,sharpie marks will disappear faster with each smaller grit sizes as you

go through them, but in reality the next grit size after 220 should be your last sharpie test. Its real hard to

get those tile out of contact once full contact is made unless your doing something totally wrong.

but then again you are doing a F 3.3 or so, a whole different animal in itself.

73 hours so far, man your arms must be soar, nice report.

btw.. hope to start polishing the 20" this week or next, more likely the latter but things are warming up.

Rick

Looking good Rich, as far as the grinding goes  you have the hard part

behind ya now..

Rick M

Rich,

         Glad to see you are making progress, grind on my friend, grind on...will be watching for new updates.

Rick

Great blog

 

I can't imagine where you find the patience, on something that rough I'd have whipped out the orbital sander for the first stint 

A novel idea indeed, but even with the proper breathing mask and such I would not bother to try that, glass dust is deadly, a slow and agonizing way to go, even grinding by hand you never want your wet get to dry, butlike

everything else if you follow the proper procedures you will have no problems, slow and easy is always best with mirror making in my opinion, you learn more..just my 2 cents.

Rick