JRM

Well done Damian, things came together nicely to say the least, looks fantastic, how I would love to look through the eyepiece bet the views are amazing.

great job and awesome build thread,years and years of starry nights for you to enjoy with the beast for sure my friend, weather permitting of course.

cheers on a project well done, time to crack the bubbly.

Rick

great work Damian, things  fitting together nicely,gonna look awesome. keep them coming.

Rick

Damian,

I am in envy now, get it all together so we can here of those great night views through the beast, can't wait for your first light.

Congrates my friend.

Rick M

More work soon and I am hoping to progress everything to a successful conclusion

Damian

You will my friend, you will....never rush perfection,time is on your side.

Rick M

Hi Derek

I normally leave the mirror about half an hour at this stage as I have that much materiality remove it doesn't make much difference.

In the later figuring stage (which still seems a long way off!) It will be a case of leaving it a lot longer possibly over night.

I don't have real a means of temperature control in my test area (the lounge) but keep the heating off as thermals distort the images

Hi Damian,

 Normal wait time for cool down to test with plate glass is around 4-5 hours, 8 for pyrex.

be careful my friend, if you test to early you may grind a hole before you know the hill is gone,

even after a 15 minute session I leave mine on the test stand for 8 hours just to be sure the 

glass has reach thermal equilibrium, I once checked it every so often just to see the changes

and believe me you will be surprise just how much it will change.

best to give it a look the next day before you start,

just my 2 cents, hope it helps.

Rick M

Looking real good Damian, the edge looks good, now to get the rest of it back without losing the edge again, your really not that far awayfrom the finish line.

Rick M

The day is getting closer for you to feel those photons touching the back of your eye as you look through the eyepiece Damian,

all those 22 inches of light gathering beauty will be a sight to behold I am sure and will make every momment of this epic

journey worth it ... and then some my friend.

I picked my glass off the bench Saturday to test the wrist, not completely better yet, but close enough, been far to long, I

plan too pour a pitch lap this weekend and get back at it  if all goes well 

Cheers

Rick M

Nice to see you moved towards the edge Damian, see... things are starting to turn for the good,I still

say slow and steady though, and beware of digging to deep a ring.

they say inside roc is a more sensitive test and the edge is looking way better inside now so things

are moving in the right direction.

can you try a shot with less lines outside focus, say five so you have same inside and outside to

compare. just a thought.

keep up the good work my friend.

Rick M

looking good Damian, should make for a great glass working table.

 Rick M

Battle has recommenced with the edge so an update later guys. 

Back to the lap

Damian

Battle on Damian, thinking it will be atleast june before I can return to it, really sucks but I am reading everything you post,

I just watch the John Dobson video, a bit rough yes but bold and to the point, no sense beating around the bush I always

say but heck I would never want to carry a tubed 20" around, thank goodness for the truss tube design.

Rick

Hi again Damian,

Well if you haven't see it go look it is a real eye opener.

Telescope Building with John Dobson (1:28:30)  in SGL.

  will have to go and spend an hour and a half watching this then

Thanks for the info Derek.

Rick M

I'm going to attempt more edge work tomorrow and after 2 hours test again. If the edge does not improve then I may need different tactics 

Damian

Damian,

What are you using to test, the 133lpi ronchi?, if so can you do a couple shots with  a lesser one say 85lpi?

it should show less difrraction and give a clear picture of the edge,just a though... unless of course you are

using the 85.

Rick

Damian,

     Just out of curiosity how much time to you leave the glass sit before testing? 

I usually leave mine for  8 hours before testing.

You are getting there,your edge is getting ever so close now.

Rick

 Looking much better Damian but you gotta love the

way diffraction makes the edge look worse then it

really is.

maybe I missed it but what do you have coming for

a focuser if I may, have to find me one of those as

well.

Rick

Damian,

             Following with interest, I'm on vacation in sunny Florida but head home this weekend, I will soon have to make 

a box to secure glass in as well, on thing though, as Nigel said earlier, using the flat tool as your pitch lap will presents

problems, you lap will be almost 3/8th inches thicker in the center which will make that area of the pitch lap softer compared

to the outer edge, will be hard to keep in full contact if not near impossible, short session and lots of pressing,you should know

by the feel of the lap but test after first round will tell the tale, after the glass  equalizes that is.

not meant as discouragement so please don't take it as such.

Rick M

doing great Damian,  there is a light at the end of that tunnel and it gets closer with every push.

Rick M

Nice to see your journey on here now Damian,will be following with interest, keep us posted, every step is a learning curve in making a mirror of that size and focal length

but learn you shall, cant wait to see the final results.

Rick M

    Did basically the same with my 12" Antares dob, little different hookup on mine though, I took the locks off and after replacing with the stronger

springs there is no need for the locks,holds collimation very well.  Nice job.

Rick