Mitchell's Telescope Making Website

Check out My Telescope Making Projects!

My 6" Homemade Telescope


I am really into building my own scopes and this is the page on my very first one. I had planned to make it a 6" F/8. It has been the standard starting size mirror since early ATM began.  It shouldn't have been too hard because at this size and focal ratio parabolizing isn't too hard or too critical. But, the mirror came out being an F/6.5 when finished, somehow I measured the depth wrong, my gap gauges were a little inaccurate. Luckily, it wasn't that much harder to figure and is will be much more portable, I'm actually quite happy with it. Also to me there is no point to making a telescope unless you make the mirror, it's like the engine in a car. If you don't have it nothing works. Plus, I am making larger mirrors now and this was be a great learning experience to start from. This is a detailed description of my endeavour to make a 6" scope. You can see more about my plan for my home built telescope(s) in my Equipment section.

NOTE: THERE ARE MANY PROCEDURES THAT GO INTO ALL THIS TELESCOPE MAKING! But there are so many other sites and books on all the calculations, and strokes, and techniques, and procedures, and parts, testers, etc. that I'm not including them on my site, not yet anyway. This is just my personal account, though it may prove useful to some for ideas and things to look out for. 

Other Information:

*TOTAL NUMBER OF WETS*: This is after all grinding and re-grinding.    #80 - 26 WETS   #120 - 14 WETS   #180 - 14 WETS   #220 - 11 WETS   25 Micron - 16 WETS   20 Micron - 16 WETS   15 Micron - 12 WETS   9 Micron - 64 WETS   5 Micron - 21 WETS   



(This does not include the 7 Hours and 20 Minutes I polished before I scratched my mirror and had to re-grind.)  

PRICE LIST: *NOTE: I'm only including things specific to this project. I have my 8 or so books and John Dobson video. I also have bought a Spark plug gap gauge, parts for ronchi and foucault testers, chain for my working stand, hotplate, ruler, some better CEO and Black Rouge polishing compounds (which is enough for DOZENS of mirrors), extra screws, brass wire brush for cleaning the lap, mirror coating stripping material, a sheet of teflon, etc, etc, etc, etc, etc. I include shipping on all items. So on ATM in general I've spent quite a bit. But hey, I love it, and thatís what high interest CD's at the bank are good for!

Object                               Price          Total

Newport Glass 6" Pyrex Mirror Kit                     $82                          $82

5 Micron, 1/4 pound from Got Grit                      $7                           $89

(2) 48X1" square tubing for trusses                     $12                          $101

(2) 16"X36" Melamine covered 3/4" board          $12                          $113

6' X 7.25" X 3/4" Board                                        $8                           $121

Bolts/Springs/Wing nuts for Mirror Cell               $5                           $126

1.52" (1/15 wave) Secondary from Antares          $67                         $193

1.52" Spider                                                        $89                          $282

1.25" Orion Focuser                                            $25                          $307

Mirror Coating                                                   $50                           $357

Paint (All 3 colors)                                             $15                           $372

Protostar Hi-Tack Flocking                                $15                           $387

Other Random Nuts and Bolts                About  $3                            $390               

Grand Total: 390$

Overall this project came out a little over the price of a commercial 6" but the experience I gained is priceless and the quality is much better!


6" Test Images

Test Images:

I only have a few images here because I'm usually just too busy working on the mirror to take pictures. These images are after I had to go back and re-grind because I scratched the mirror. 

8 Hours

Here is what the mirror looked like after 8 hours of polishing; a deep center hole and TDE. The TDE is exaggerated because of the second curve (the hole) in the glass.

8 Hours, 30 Minutes

After much trial and error during the first 8 hours of polishing I finally got rid of the center hole. There is only a small bit left. It only took 30 Minutes of work. The image above shows the mirror at pretty much its worst. Now it is pretty good other than the TDE. This image isn't very good, fairly grainy but I was too lazy to take another.

16 Hours, 20 Minutes

There is still a small central hill in the tiny, tiny remnants of the hole. The mirror is now a bit of an Oblate Spheroid (shallower than a sphere). So some parabolizing strokes should get it spherical, and eventually parabolic.

17 Hours

The Mirror is now getting close. It is still a bit of an oblate but it is reducing nicely. The TDE is almost completely gone! The center hole with a hill is completely smoothed over too! The parabolizing strokes fixed 3 things at one time, the oblate shape, the TDE, and the surface roughness. I will continue with this for a little more time and the mirror should be completely spherical. 

23 Hours, 5 Minutes

Well it took a bit longer to get here than I thought because at the ATM meeting we found I still have 1/2 wave TDE. You can see it in this picture which I took with a MUCH nicer digital camera. Other than the TDE though the mirror is nice, not quite spherical because I've started short strokes to rid the TDE and that turns it back to an ellipse which luckily, is easy to correct as you can see I did before in earlier images.

35 Hours, 20 Minutes

The Mirror is getting really close now! It is still a little bit oblate but shouldn't be hard to work to a Sphere then a Parabola! You can see the TDE IS FINALLY GONE!!! When I'm completely done the lines will bend the opposite way a little bit. This image is the opposite of all the others here; it is INSIDE focus so the lines are opposite of the images above. It is already 1/1.6 Wave!

THE FINAL TEST IMAGES: Approximately 41 Hours:

The first image is Inside the ROC, the second is Outside.

The mirror has a 1/12.5 Peak-Valley Wavefront Error Rating! Strehl Ratio is slightly above .98. The physical surface RMS error is 5.9nm. The overall correction is .042, with the perfect being .048, so my mirror is only .006 undercorrected. As general opinion goes if you must leave a mirror one way or the other Undercorrected is better than Overcorrected so my mirror is good in that respect also.

Beside the numbers, the overall mirror is very good. The edge is fairly good; there is a diffraction ring, though slightly dimmer on the right. The very last mm or two is turned slightly down, estimated to be about 1/15 wave or so. It is slightly accented by the fact that there is also an equally narrow high zone just inside it from where my TDE and TUE originally merged, just the tail end remnants of it. The surface is very smooth, only a very slight roughness/artifact detectable in the center, but it will be covered by the secondary. There was also no detectable astigmatism by the ronchi test.

So all in all if I do say so myself this is not only an excellent first mirror, but a very good mirror in itself! Scroll to the bottom of the page for the Figure XP file.


6" Mirror Log

Here is my Mirror Log, check it out!  

11/2/04: I ordered a 6" mirror kit from Newport Glass. I just called and ordered over the phone. It should be here in 7-10 days, (expecting about 14 though).

11/18/04: It's here! My mirror kit came late this afternoon. I know I said about 7-10 days but they had to make the kit and it only took 6 days during shipping. Checked it out and it's all here, the blank, tool, grits, etc. Some specifics though, The Blank is nice, already beveled, a bit rough looking but it should grind off in a couple of wets. The Tool is also nice, it is the same thickness as the Blank (about 1") and it has 5 small circle groves radiating out from the center. You may think 1" thick isn't much but it seems thick and is hefty. It also comes with grit sizes 80, 120, 180, 220, 25 micron, 20, 15, and 9 micron plus Cerium Oxide polishing compound. It is amazing how small the 80 grit is, smaller than salt! The kit also came with two 1/2 pound tubs of medium hardness burgundy pitch (I later found this was actually Acculap, a substitute that is OK) to make a polishing pitchlap with.

11/19/04: I have been cranking away already. I did about 12 wets with 80 carbo. I did 5 and then cleaned it all up, rebeveled the tool, and did another 7. I can already see a small curve in the mirror too! The bevel on the mirror is almost the same but I had to rebevel the tool once already in between 5 and 7 wets.

11/20/04: Well today was wet and rainy, but I did make some progress. I used my 2 Million candle power spot light to act as the sun and wet the mirror. I did my best to find some focus on a board and concluded it was much too long. I did 2 more wets with 80 carbo and heavy pressure and then rebeveled the tool. It seemed to help a bit but still too long of a focus by about 2-3 feet. I won't be able to tell till I do my next test. Which is, in true ATM (Amateur telescope making) style, using an 18 inch stainless steel ruler as a straight edge I got today, and a spark plug feeler gauge to measure the saggita. The light ray optical test is okay, but the gauge and ruler will be the best for measuring the sagitta. Also, I am starting a price list to see the cost of this project.

11/21/04: Well I actually got my gauge today! It has different blades from .006 to .026 of an inch. By combining blades I figured out my mirror has a sagitta (center depth) of .030 so I did 4 more wets with 80 carbo and the depth went to .035. Then I had to fix my grinding board because a cleat was coming loose so I had to clean everything up and just decided to quit for the night. But anyway, I need to get the sagitta to .047, so just .012 left to go!

11/22/04: Well I went down to get set up to start grinding; I checked the saggita to make sure I got the same as yesterday (.035). And there in front of my own eyes I got .040! Thatís 5 thousandths of an inch deeper. I suppose I was measuring wrong.  Also I noticed the bevel on the tool was getting a little small so I widened it a bit. So At this point I didn't want to go too deep so I just did 3 wets with heavy pressure. It came out to be about .044. So I just have .003 left to go!

11/23/04:  I rebeveled the tool a bit but really not enough (Read on this has consequences). I did just 1 wet with very heavy pressure. After I was done the tool looked totaled! Okay, I'm exaggerating but there were HUGE chips all the way around. Some were about 1/8 of an inch wide or more! This will be one of my learning experiences, always have a good bevel! But I was applying unusually heavy pressure too. So I got it to just over .047! I also held the mirror up to the light and tilted is back and forth and it appeared by the light and dark spots that there were holes and hills, I think from the huge chips grinding all over. And before I start Fine grinding the mirror needs to be spherical. So I did 1/3 diameter center over center strokes and some "W" strokes; after 2 wets, one with the tool on top (TOT) and one with the mirror on top (MOT). I use the mirror on top then the tool so the curve doesn't become deeper because I already have it as deep as I want it. It looked all evened out, the high-low spots seemed gone.

11/24/04: Well I did 2 more wets with 80 carbo, 1 TOT and 1 MOT just to make sure it was all fairly evened out. Then I carefully cleaned up ALL 80. I probably didn't do a good enough job, we'll see. So, I measured the sagitta and it was about .046, just about right. So I started with #120 grit and did 2 MOT, 2 TOT, 2 MOT, 2 TOT, 1 MOT and then cleaned up. The sagitta was then about .045, just a tad shallow. So when I grind again I'll do an extra 2 or 3 wets with the mirror on top to deepen it to the right sagitta again. 

12/1/04: Been a real long Thanksgiving weekend for me. I took a break for awhile, working on the mirror. But now I'm back on it, I measured the sagitta and it was about .046. Then I did 3 MOT, and 2 TOT wets. The #80 pits seem gone after 14 wets with #120! I can only find 1-2 abnormal sized pits that aren't really that big; I guess tomorrow I'll move onto #180!

12/2/04: Well I couldn't find anymore large pits so I'm ready to move on! I rebeveled the tool and cleaned up all #120 real good. It took me a long time to clean though so I'll move on tomorrow. But I also got an old bike tire and took off a lot of spokes that I'll use for the spider. And I'm in a lot of Yahoo Telescope making groups and got a list of some parts to make a Ronchi tester.

12/3/04: Well I was advised to do a sharpie test by some people on the yahoo groups; by drawing on the mirror, with of coarse a sharpie marker. Then I did some short strokes, check to see if it's wearing evenly and continue, etc. I did it 3 different ways. I did one way with grit and just did 1 MOT wet so I wouldn't just waste the grit. But on one occasion I realized the mirror was severely sticking while going over the center, this was when I was using no grit. I also noticed it when I did it with water; I had heard of this problem and was nervous. I shot a message over a yahoo group; I was told the center was simply a hyperparaboloid. This was because I had been using too long a stroke the whole time, and not turning the tool and mirror enough. I was quite sad, I thought my mirror would be very hard to fix. But I was told all I had to do were some short "W" strokes, basically the normal stroke but a bit shorter. I did 2 MOT then 1 TOT. After I dried it I repeated the test. The sticking was reduced 75-80%! It was actually getting better on my first try. After that it was getting late so I just quit for the night. But later that night I also got the parts to build my Ronchi tester.  

12/4/04: Checked the sagitta and it was right on. I did another 2 TOT and 1 MOT wet, should be done with #180 soon.

12/7/04: Ordered a grating from William-bell, It is the last part I need to build a Ronchi tester; it is shipped first class so should be here the 10th or so.

12/10/04: Well the grating did come today hopefully my dad will help me put together the tester this weekend. It also seems I'm still out of contact a bit so I need to continue with #180 for awhile. 

12/15/04: The tester is basically built, needs some improvements. I also did 1 MOT and 1 TOT wet. The mirror and tool are getting in better and better contact, so I am becoming spherical which is where I want to be.

12/22/04: Man, there's no way I didn't work for this long, but I suppose the calendar doesn't lie. I guess I stopped after my tester wasn't the way I expected. I'm going to start cranking away again though. I did 3 TOT and 2 MOT wets with # 180. I'm now as close to a sphere as I can tell. I will most likely move on to #220, cleaned up all #180, so I'm all set to move on. Also I start a 10 or 11 day break for Christmas tomorrow, since I have so much time off I want to finish at least 2 more grits. I'm staring #220 now so I will finish #220, and 25 micron, then there will be only be 20, 15, and 9 micron before I can polish! And there are other numbers for 25 micron and the others, like 400, 800, etc, but when you get to those final grits they are sometimes labeled as microns.

12/25/04: Merry Christmas! The only thing I got to say is I found an old lamp shade and the top ring is 8" across, which is how big I need it and there are 3 supports going to a center ring, it might work as a spider but I plan on using a wooden square tube, so maybe not.   

12/26/04:  I did the sharpie test twice but with a pencil, the results look alright, also I'm finally moving on to # 220! I did 1 MOT & 1 TOT wet.

12/28/04: I did 4 MOT and 2 TOT wets. I also rebeveled the tool, should be the last time I have to do it since I haven't had to do it since rough grinding. 

12/29/04: I did 2 MOT and 1 TOT wets. I've done 11 wets with #220 and I think the mirror is as good as it will get with this grade. I really flew though #220. I Cleaned everything up; I'm moving on to 25 micron!  Also, I ordered a re - print book on telescope making "Make Your Own Telescope" from, it cost $10.17! It is rated VERY highly too!

12/30/04: I did 4 TOT wets with 25 micron. My kit doesn't come with 320 so I will have to work on 25 micron for double the time. Also with the grooves in the tool all the grit goes into them so no more MOT wets till polishing I guess. But when working with microns the depth will change very little. Right now the sagitta is .048. Also, down this level I have to start using suspension. This is when you just mix the grit with water and squirt it on with a squeeze bottle. I started out by adding some grit then adding about that much water 2 times on top, it was way too much water; I couldn't grind because there was too much water, so I got stupid and added all but 2 or 3 teaspoons of my 25 micron to it. Fortunately it got much better, still too much water though, so I let it sit for awhile as much of the grit went to the bottom as possiable. Then I carefully squeezed out a little of the top water, I barely lost any grit. So now I have the right Grit to Water Ratio, this was undoubtedly one of my "learning experiences" 

12/31/04: I did 6 TOT wets. That makes a total of 10 wets with 25 micron. But since I have no 320 I will probably have to do about 6 - 8 more wets before I can move onto 20 micron. The sagitta actually seems deeper, it's at just over .049, I think it's because I've been putting the pressure on the center on the tool, but thatís good, I want it to be f/8 or just under.

1/1/05: I did 1 long TOT wet. I also had a small scratch yesterday or today I think, it was shallow but about an inch long! It ground out in a wet or two though. Happy new year!

1/2/05: Did 3 TOT wets, I'm almost done with 25 micron! 

1/3/05: I did 2 TOT wets, I should probably do another few but the surface is quite good and I'll just do an extra wet or two with 20 micron. So I'm finally done with 25 micron after 16 wets!

1/4/05: I got my book from, Building Your Own Telescope, by Allyn J Thompson. I also managed to salvage all the 25 micron I wasted in my learning experience with suspension. I just drained the water, let the grit dry, and then crushed it back up, it should be alright.

1/7/05: I cleaned up all the 25 micron. I'll move onto 20 micron soon. After 20 micron I'll only have 15 and 9 micron before I can polish! My goal is to have the mirror done by the first of March, just under two months! 

1/11/05: I finished setting up for 20 Micron with a few things. School is keeping me busy but hopefully I'll start soon. 

1/16/05: Finally started 20 Micron. I did 2 TOT wets. Also, I'm starting a big science project for school soon. I'm researching different kinds of telescopes, and I've found about 20 kinds so far. But I won't do them all. The great part is I can use the scope I'm building as a model! I'll have till March, 21 so it'll be tight on time, but I think I can do it. I guess I have more motivation to finish now, it's "Homework"    .

1/17/05: I went to work today and noticed the plate glass tool had an "Internal fracture". It was fractured a good inch inward from the out side but does not come out all the way to the edges, which is really odd. But it appears to still be attached and not going anywhere, it's just one of 3 Massive chips and fractures, but this one is on the top. Anyway, I did 4 TOT wets, probably just 2 more to go!

1/20/05: I did 2 TOT wets with 20 Micron, now I'm done with it! I only did 8 wets total but that is typical for an abrasive this size. Now I'm moving on to 15 Micron! 

1/24/05: I cleaned up all the 20 micron. I'm all set to do 15 micron! The mirror is now quite reflective when held at an angle toward the light. After this I just have 9 Micron, and then I polish! 

1/25/05: I realized I have so little time to do the mirror now that I account for about three weeks for it to get from me, coated and back. I decided to start cranking; I did 8 TOT wets with 15 Micron, now I'm done with it! ALSO, I learned another lesson; don't work a wet all the way to the end. I have been told this before, but I never took it really seriously. And of course I wanted to get that last bit of work in so I ground the last wet a lot longer than I knew I should have; now I have a pretty 1/8 inch long scratch at the edge of my mirror. But I'm not worried, I plan on doing 10 wets with 9 micron because it is the last grit, and I'll be sure not to work the wets to the bone! Now I can start 9 Micron, my last grit! 

1/27/05: I cleaned up all 15 Micron. I'm now ready to start my last grit, 9 Micron! Also, after a bit of experimenting a few days ago, I've basically got my Ronchi tester working too! Not totally, but I'm getting there.  

1/29/05: I did 1 TOT wet with 9 Micron; I got rid of the first scratch and now have a nicer straight 1/8" long scratch; probably from working the grit too long again. I only did one wet cause I wanted to test the mirror a bit, but I realize now I really can't test till it's polished.

1/30/05: Did 5 TOT wets. The scratch from yesterday is still there, looks exactly the same. And to tell you the truth, it won't hurt the optical quality at all, so if it isn't gone after polishing I really don't care. Everyone stresses over them because they just look bad, but I'm on a deadline and this scope isn't meant for the best views or looks. Speaking of deadlines, I honestly don't think I'm going to be able to finish the scope for my project. Sadly, It's time I look for a new project.

2/19/05: I haven't worked in awhile. I had a lot of homework. And I got a computer game that I've been sucked into for awhile. Also, I had to pick a new project for my science assignment. I'm very relieved. I did 3 TOT wets. When I was grinding the 3 wets I did each set of ten strokes I set the tool down onto the mirror and without pressure moved it half way off the mirror then back to get rid of the air bubbles. I guess I had too much contact. I think I will leave most of the air bubbles there as a cushion now and just try and get out a few of the light swirling scratches. So as a result I now have not one, but 5 scratches, most light and swirls. One is the main one from before. The others will hopefully grind out, (replaced by more I'm sure). The very light ones should grind/polish out though. So I should be done with 9 Micron soon. Also, I have decided to name my scope. I will paint on the side "Learning Experience". It's the "perfect" name.

2/21/05: I did 2 TOT wets. I left most of the air bubbles in as cushion and it worked great. The only scratches are the main one near the center and another one thatís fairly big on the edge. I also extended the second wet by adding water as needed. This is to help "Simulate" 5 Micron a bit because I don't have it. But now I think I'm near ready to polish!

3/10/05: I got sucked back into my computer game. But I've finally been able to break the hold it had on me. I realized how much I really missed working on my mirror so I'm taking a break with the game till my mirror is complete, well, thatís the plan, lol. I did 4 TOT wets. I did three then I forgot the sweatshirt I had on had a brass zipper. When I wiped the blank on my shirt there was some "transfer" of brass. So I did one more wet and it disappeared. Now there is only the scratch in the center which is small and the one on the edge; And of course some "Microscopic ones". I'll probably get some 5 Micron too, so that might help with the "Microscopic" scratches, even though they would polish out.

3/24/05: I finally went back to 15 Micron, I did 1 TOT wet. The scratches are much smaller! What difference one grit can make!

3/25/05: I did 2 TOT wets, the scratches are basically gone. I'll do another wet or two then it's Back to 9 Micron.

3/26/05: I did another wet with 15 Micron. I have decided this is far enough and it's time to move back to 9 Micron, so I cleaned up and Iím ready to start 9 Micron.

5/16/05: Yes, it's true; the game again relinquished its hold on me, lol. The game is Warcraft III. I don't know how long this will last so I'm going to crank away again. I locked the game in my safe so unless I unlock it I can't play. Hopefully as I go to unlock it, I will be more compelled to work, lol. Again, "at least thatís the plan". I will also be ordering 5 Micron.

5/19/05: 3 TOT wets with 9 Micron

5/23/05: 2 TOT wets, ordered 5 Micron from 

5/25/05: 4 TOT wets. I'm now done with 9 Micron; the surface of the mirror looks pretty good

5/31/05: The 5 Micron arrived; I'll be grinding on it soon

6/4/05: Tomorrow is my Birthday! I'll be 14. I'm set up for 5 micron; I'm basically ready to start grinding.

6/11/05: Did 2 TOT wets with the 5 Micron.     

6/22/05: 3 TOT Wets. I have to be careful now, the mirror and tool get stuck together sometimes at this small grit size and that can lead to scratches.

7/17/05: I've decided that I am done with grinding unless I need to go back due to scratches from polishing. I cut out two six inch diameter circles from 3/4" board. It is not plywood but something like it. I had to use a hand saw instead of an electric one because the blade is broken and it seems we will never get a new one. I cut off parts to make it a circular as possible. I'll just use a sanding block to finish them up nice. Then they will be attached and sealed to form the substrate for the polishing lap.

9/11/05: I finally got around to finishing one of the wooden circles; I will do my best to finish the other one soon. Also, this is the 5th anniversary of 9/11  

9/17/05: I finished the other wooden circle for the substrate of my pitch lap.

10/11/05: I am not completely clear on the rest of the optical work to be done so I ordered a copy of John Dobson's Telescope making video. It's the only video out there, and it's made by the famous John Dobson. I might have given up on using the two wooden circles as a substrate because I forgot I can not use a flat piece of wood so I think I might be going back to the tool since the surface is already the correct curvature. It may seem a waste of time, but it is really just another lesson learned! I can sand them up nice and maybe still use them for bearings or something. 

10/31/05: Happy Halloween! A very happy one to me indeed, I received my video today. It was pretty good. John Dobson does things really "old school". Not that there's anything wrong with that. But it was still helpful. Worth the 43$? I think it is worth something more like 29.95 like most videos.   

11/5/05: I DID IT!!! I actually made the pitch lap! I used a simple process a good friend and fellow telescope maker showed me. It is obviously not perfect but it came out better than I could have ever hoped. I had a lot of help from my dad too. 

11/6/05: I Polished for 20 Minutes. 10 TOT, 10 MOT. I did one set in the morning and the other in the afternoon. There seems to be a slightly defective facet on one edge, it overhangs a bit so Iíll just bevel it more. There were also a few lines on the mirror not polished as well. I found that culprit, a piece of pitch, about 3 or 4 mm long stuck to the edge of one facet. I fixed that after the first 10 Minutes. I'll be more careful about this in the future. BUT IT AIN'T SO FROSTY ANYMORE    . Yep, after 20 Minutes of polishing the mirror has the SLIGHTEST shine to it. Even only after 10 it did. Probably do in part that I have a rougher, faster-cutting grade of polishing compound. So it will polish fast.

11/7/05: I polished for another 20 minutes. 10 TOT, 10 MOT. There are still those light areas in between the center and edge but they aren't getting worse so Iím not worried. I got my Ronchi tester working! Then, later IT ALL WENT WRONG. Sometimes outside of focus the ronchi image wasn't what it was supposed to be. I tried measuring the focus with a flashlight. I got two different conclusions; either Iím 2 1/2 feet too long or 1/2 feet to short. And my eye focuses the light from a flashlight different than on a piece of paper, both should be the same. Everything WAS great, couldn't have been better. NOW THINGS ARE SO MESSED UP. It couldn't get any worse unless I dropped the mirror and broke it in two, and if the mirror is really messed up, even that may be better. RIGHT NOW, I JUST DON'T GIVE A DAM. I'll eventually calm down and maybe everything is ok and I was just overlooking little things, we'll see after my cries for help get answered by the ATM'ers on the yahoo groups.

11/8/05: Well following the advice of other ATM'ers I'll continue to polish even though a fatal flaw is apparent. I did another 20 Minutes, 10 TOT, 10 MOT. Perhaps something is being over looked but everything seems to point to a problem. The Ronchi images have become a bit clearer and it still seems there is a problem, a sphere within a sphere. But Iíll go with the elders on this one and polish more before deciding on whether or not to go back to grinding.

11/10/05: Well I'm glad I went with the elders! After using 3 "masks" made from cardboard to check where the different zones of the mirror were focusing it seems the focus from center to edge is off by less then 1/2". Somehow I have been measuring the sagitta way off. Perhaps the ruler is crooked, or the spark plug gap gauges weren't resting flat but the mirror is an F/6.5 now! About .020 inches deeper than I thought it was! Quite a big misreading but I am actually kind of happy. The F/6.5 shouldn't be too much harder for me to figure but will still teach me a lot about the figuring. I am glad I'm finally not so frustrated and I can just keep right on polishing. 

11/11/05: I polished for another 10 Minutes, 5 TOT, 5 MOT. I would have done more but the channels are closing up already and need to be re-trimmed.

11/12/05: Well I got a new shelf for all my ATM stuff; A heavy duty steel shelf with adjustable shelves. Everything looks much neater now; it's not all over the floor. I'll post a picture soon. 

11/13/05: Retrimmed the lap; Made the channels nice and wide so I can hopefully get a full hour of polishing before I need to retrim again. But my backs hurting today so polishing will have to wait a day or two. 

11/14/05: Did 40 Minutes, 20 TOT, 20 MOT. The channels still closed up about the same as before; time to re-trim.

11/15/05: I re-trimmed the lap (I actually did it this time with only minor assistance from my dad). It looks like I am going to have to re-pour the lap though. It is getting to thin and I can't get it to press correctly. Not a very uncommon thing though. But a lot of good will come from it. I can make it the right hardness so much less re-trimming will be needed and I can make the edge a more uniform beveled one to prevent Turned Down Edge (TDE) from too much polishing at the edge

11/16/05: Well since I have to re-make the lap and it looks like I will need a hot plate a bit more often then I thought originally I decided to buy one. The same one I borrowed from my neighbor, for less than ten bucks. It heats up really fast because it has one big coil that touches directly to the container youíre heating.

11/17/05: Took the pitch off the tool by freezing it for 5 minutes to make it brittle then CAREFULLY chipped it off with a hammer and large screw driver; Came out pretty good. 

11/18/05: Downloaded a simple program called Ronchi for Windows. Itís a great easy to use program for direct comparison of the ronchi test.

11/20/05: I'm going to try and keep my entries a lot shorter now just because I don't feel like typing it all out and it's not necessary (I'll try anyway). I re-poured the pitchlap today. 

11/21/05: Polished for 50 Minutes.

11/22/05: Polished for 20 Minutes. I'll have to find a cooler place or harden the lap because the channels already closed up. 

11/26/05: Re-trimmed the lap.

11/28/05: Polished for 1 Hour. I let the lap sit in cold water before polishing so it is harder and lasts longer without re-trimming. 

11/29/05: Re-trimmed and Polished for 1 Hour.

11/30/05: Re-trimmed the lap. Then I polished for 1 Hour. Then I re-trimmed again so I can keep going tomorrow. But the lap is very thin now (about 1/16") so I'll have to add pitch. I'm really polishing away!

12/01/05: Polished for 1 Hour.

12/03/05: Had to add more pitch to the lap since it was so thin. Basically like re-making the lap but just added more pitch. I'll be back polishing soon.

12/04/05: Took awhile to cut the new channels but its all set.

12/08/05: Polished for 20 Minutes. I Used a much more random stroke to break up zones as someone advised me to do. Worked great, the test images show it improved greatly. I would have gone more but I couldn't even move the mirror when MOT, maybe cause the channels were a bit thin, but not too thin. It took me awhile to get back to work with school. I'll have to re-trim then see. what happens.

12/11/05: Long couple of days, been out in the snow. Anyway, I re-trimmed the lap thinking that was the problem for the sticking but it wasn't. I realized after cleaning my mirror with turpentine to try and remove little pieces of pitch (which it didn't) I forgot to wash the mirror in clean water. After the 20 minute session there was a layer of residue on the lap. It took awhile but I got it off. I was supposed to go with a friend and fellow ATMer down to Tinton falls to an ATM meeting last week but it got snowed out. So it got rescheduled and I'll be going down tomorrow!

12/13/05: Last night was a blast; I met quite a few mirror makers. Got my optics tested on an excellent professional (still made by the guy) tester. Looks like I got a hole in the center, as I knew, but it's pretty large; also a fairly large TDE. He showed me many things that will help a lot! Also, I haven't been using enough pressure in polishing so Iím only about 1/4 of the way there after 7 hours . Bummer, but thatís okay, I'm willing to do the work. Feel bad for the friend who brought me down. his 12" is really astigmatic and he's going back around 60 hours of work. All in all a great night though!

12/14/05: Even more disaster! I accidentally bumped the mirror and tool together. 3, 1/8" scratches, a 1" long scratch made of lots of short little scratches, all very deep. I'm not going to sit around and whine. I knew they wouldn't polish out, I could feel they were deep. I ripped off the pitch and mixed a bottle of 20 Micron up. I did 6 TOT wets. Yup, back to 20 Micron. But Iím going to do this fast and carefully. I'll be back polishing in a few days. After six wets the scratches are almost completely gone. I'll do a bit more to be safe. I'm glad I didn't just go back one or two grits and jumped to four because I could feel how deep these scratches really were.

12/15/05: I did 2 TOT wets with 20 Micron. Cleaned everything up and skipped down to 9 Micron because I thought the scratches were gone. I did 30 TOT wets. One of the 1/8" scratches is still just barely visible. I'll do a bit more with this grit maybe then move on to 5 Micron. Its ok I had to do a lot of wets because now I know there are no larger pits or scratches. Plus the jump from 20 to 9 Micron was sort of a big one so now it should be good.

12/17/05: Did 10 More TOT wets with 9 Micron. The scratches are almost all gone, and it's not getting any better so I cleaned up and am ready for 5 micron

12/18/05: Did 16 TOT wets with 5 Micron. Cleaned up and made the pitchlap. Then I did 15 minutes of polishing. This time I'm keeping a detailed log so I'll just post the amount of time here.

12/19/05: 45 Minutes of Polishing.

12/21/05: 30 Minutes of Polishing.                                                                                                 

12/22/05: 30 Minutes of Polishing.

12/23/05: 30 Minutes of Polishing.

12/24/05: 30 Minutes of Polishing.

12/26/05: 1 Hour of Polishing. I got a bunch of books on ATM for Christmas along with a laser pointer to test the polish. Merry Christmas!

12/27/05: 30 Minutes of Polishing.

12/28/05: 30 Minutes of Polishing.

12/29/05: 1 Hour of Polishing. 

12/30/05: 1 Hour of Polishing.

1/3/06: 30 Minutes of Polishing. Happy New Year!

1/5/06: 30 Minutes of Polishing.

1/7/06: 30 Minutes of Polishing. After much trial and error I managed to cleanly get the center hole out. Now there is just a slight turned down edge. I finally put some test images up. 

1/8/06: 30 Minutes of Polishing. 

1/10/06: 30 Minutes of Polishing. 

1/14/06: 30 Minutes of Polishing.

1/16/06: 20 Minutes of Polishing. I'll be doing most sessions now in order to correct defects.

1/18/06: 15 Minutes of Polishing. 

1/19/06: 30 Minutes of Polishing.

1/20/06: 30 Minutes of Polishing.

1/21/06: 30 Minutes of Polishing.

1/23/06: 30 Minutes of Polishing.

1/25/06: 30 Minutes of Polishing.

1/26/06: 30 Minutes of Polishing.

1/29/06: 45 Minutes of Polishing.

2/3/06: 30 Minutes of Polishing.

2/4/06: 30 Minutes of Polishing.

2/8/06: 15 Minutes of Polishing.

2/11/06: 45 Minutes of Polishing.

2/15/06: 25 Minutes of Polishing.

2/17/06: 15 Minutes of Polishing.

2/19/06: 1 Hour of Polishing.

2/20/06: 30 Minutes of Polishing.

2/22/06: 30 Minutes of Polishing. 

2/23/06: 30 Minutes of Polishing. 

2/25/06: 40 Minutes of Polishing. 

2/26/06: 12 Minutes of Polishing. The mirror is now about 100% spherical and Iím just doing very short sessions to slowly continue work towards the parabola. Now I measure in times around the mirror which takes about a minute and a half because I need to work very slowly now.

3/2/06: 15 Minutes of Polishing. After going to another ATM meeting we found under the good tester my mirror still has about 1/2 wave of TDE. There is also central hole which is nothing to worry about. His tester is very nice because it is hooked up to a camera so you can see it on a TV screen and adjust the view. 

3/4/06: 37 Minutes of Polishing.

3/5/06: 20 Minutes of Polishing

3/8/06: 1 Hour, 5 Minutes of Polishing. 

3/9/06: 25 Minutes of Polishing. 

3/12/06: 1 Hour, 25 Minutes of Polishing. 

3/13/06: 1 Hour of Polishing. Ever since I went to Gordonís last I have been trying and trying and trying again to rid the TDE and I FINALLY found a way to do it, following the advice of a friend and fellow ATMer. It is almost completely gone for real this time! Now I just have to smooth things over again and work towards the parabola, it should be slow and steady work to the finish now!

3/14/06: 45 Minutes of Polishing. False alarm; the edge is actually only a little better...

3/19/06: 25 Minutes of Polishing.

3/22/06: 15 Minutes of Polishing.

3/25/06: 30 Minutes of Polishing.

3/26/06: 45 Minutes of Polishing.

3/27/06: 30 Minutes of Polishing.

3/29/06: 30 Minutes of Polishing.

4/11/06: 15 Minutes of Polishing.

4/17/06: 15 Minutes of Polishing.

4/20/06: 15 Minutes of Polishing.

4/22/06: 15 Minutes of Polishing.

4/23/06: 4 Hours, 30 Minutes of Polishing.

4/24/06: 30 Minutes of Polishing. Did all this work lately for the ATM meeting in Tinton Falls tonight. I Haven't been there in awhile. Yesterday even though I worked a lot my strokes were too short for awhile so it didn't get as far as I wanted to.

4/24/06: Well the ATM meeting was a smashing success! I found out many things. First of all, after 14 hours of work since the last meeting, the TURNED DOWN EDGE IS ACTUALLY GONE. CONFIRMED IT IS GONE!!!!!!! WOOOOT!!! Just that would have been enough to make the night great. Then, since my pitchlap was EXTREMELY thin we re-poured a new one (with real pitch this time not acculap). We used a nice mold to make circular facets. It works great. We took some Foucault readings using a 6 zone mask and concluded my mirror was a 1/1.3 Wave Parabola and a 1/3.6 Wave Sphere. We did a few little things on the new lap amounting to 10 Minutes work and this little bit increased it to 1/1.6 Wave Parabola and a 1/6 Wave Sphere! Maybe it will be 1/10 wave when it's done! Though I could settle for a bit less with no regret. I put up a new test image. I'm really closing in now. Some slow steady work and I'll be finished before my goal of my birthday (June 5th, this is of course so I can get a 10" mirror kit ). Of course I made this goal after I missed my first goal of one year although many peopleís first mirrors can take a few years. I'll get it all done in good time!

5/8/06: 6 Minutes Parabolizing before going down to the meeting tonight. It was another great ATM meeting. My 6 minutes of work at home got the mirror to a 1/1.91 Wave Parabola and a 1/15.48 Wave Sphere. It will probably become a worse Sphere and a better Parabola now! I did 6 more minutes parabolizing, working a bit more over the center got me a 1/2.14 Wave Parabola. I won't give Sphere ratings now because they are getting worse as they should be as I move away from a sphere to a Parabola. 6 More minutes working almost all COC (center over center) got me to a 1/4.74 Wave Parabola! Better than 1/4 wave, some people consider a mirror done, this is really the absolute minimum acceptable so I'll do a bit more to get it better. 1 time around COC should bring my edge down and make the mirror a lot better, maybe even finish it! We'll see.

5/14-18/06: Over the last few days I built my first Foucault Tester! I used my old Ronchi Tester to hold the KE and it rides on top of the stage. It is typical of many testers. I'll put a picture up and update my testing section soon. I managed to take my first readings too! Two sets, they are fairly close to the ones taken at the ATM meeting. They are obviously a bit off as this was my first time doing the test. I got around 1/3.5 and at the ATM meeting we got 1/4.7 I trust the other numbers better. We'll see as I conduct the test more.

5/20-21/06: I built my first Grinding/Polishing stand! Man did it come out good! It is way better than most stands and looks good too. I put a picture up on my 6" Homebuilt page. Also put up an image of my Foucault tester on my testing page. I have also been working on the mirror. After 3 very short sessions I think I am done! We'll see when I go to the next ATM meeting.

6/5/06: Happy Birthday to me! After an ATM meeting last night we concluded my mirror was about the same and after 3 short sessions my mirror got worse and worse lol. All part of the learning experience. It's not too bad, about 1/3 Wave.

6/11/06: Built the two square boxes that will become the upper and lower OTA's. I will connect them with two pieces of 1" square tubing I got a few weeks ago. I also cut (2) 4" side bearings. I'll be ordering more parts soon and will build the rest of the scope with 1/2" wood I got along with the square tubing a few weeks ago. After the ATM meeting I took some suggestions and made some modifications to my tester, just a few more to go. I'll try and get some work done on the mirror too.

6/25/06: Went on a vacation so I haven't had a lot of time. I sanded down both sides of my 4'X2'X1/2" board for the telescope base. It is a bit on the thin side but I think I will manage. I ordered the spider more than a week ago and that should be here within a week hopefully. I also ordered the secondary mirror and focuser yesterday. Waiting to do work on the mirror till I get most of the scope done that way once the mirror is done I can put the final touches on everything while the mirror is being aluminized. I'll do some on the mirror soon though. Still have to get around to finishing the last few modifications on my tester too. All in all, still making some progress.

6/28/05: The secondary mirror arrived from Antares! Fast, only 4 days in shipping. I picked up a couple of parts for the mirror cell to which I'll start tomorrow. The focuser and spider should hopefully be here by the end of the week, probably next week.

6/29/06: I built the mirror cell today. It looks great. I just have to trim the sides a bit. I was able to use one of the 6" disks I originally cut for my lap base. E-mail says the spider shipped today and should be here Wednesday most likely.

6/30/06: Surprisingly the spider and focuser both came today! I'll attach these soon.

7/1/06: Attached the focuser. Had to pick up a 1&3/4" hole saw to do it. Came out pretty good; Focuser has a lot of travel which is nice I also thought of a new way to attach the square tubing which will change the way the OTA sits and will look cool. You'll see what I mean when I put a picture up when it's done.

7/3/06: Attached the Spider; Looks good.

7/24/06: Over the last few weeks I've attached the two truss poles to the lower OTA. Got the holes drilled in the upper OTA. After the ATM meeting tonight we found that the center of my mirror was way overcorrected while the edge was still way to high. I made the center deeper when I brought the edge down a bit. I'll have to go back to spherical then parabolize again since you can't bring the center up and bringing the edge down brings the center down even more. This isn't uncommon; some people have to parabolize then sphereize dozens of times. 

7/25/06:  I wanted to do a quick run on something in the sky to make sure I had enough focus. So I plopped in the mirror and secondary. The ONLY ALIGNMENT I did was making sure the diagonal pointed toward the focuser by eye-balling it. I haven't yet attached the upper OTA (hence this test) so I was holding it in my hands and could slide it up and down the two "truss poles" of square tubing till the object focused with the focuser at it's half way racked out point. I found Jupiter quickly and with just a slight slide of the upper OTA it was focused! I don't mean perfectly, but it was round, and I could even see one of the bands! This was with NO COLLMINATION AND I WAS HOLDING THE WHOLE UPPER OTA IN MY WHOBLING HANDS!!! So then I defocused the image. The collimation was so far off only half the mirror could be seen in the de-focused star image, the other half was missing the secondary completely! The secondary shadow was on the side of the mirror you could see, it too was so far off the shadow was cut in half by the edge of the mirror image from the defocused image. So then I swung around to a bright star, it wasn't pinpoint, it was stretched in a short bent line, sort of like this mark) But hey, I was holding the whole upper assembly in my hands! It did move around quite a bit. Anyway, my measurement is where it needs to be so I got it marked now and I'll attach the upper OTA soon. Not bad for a 1/5 wave mirror that has a hole and a high edge and is pretty rough, sitting in a scope that isn't aligned what so ever, with the other end being held in my hands! After over a year and a half of work, my first "image" was quite exciting. I was amazed at the "quality" of it even with the TERRIBLE alignment.                                                                                                                                           

7/26/06: Connected the upper OTA box and sawed off the excess square tubing. The whole OTA is now together. I just have to attach the side bearings.

7/27/06: Cut the parts for the mount! Due to the way I decided to mount my truss poles I ran into a bunch of clearance problems with my original idea. But I think I have them all sorted out now.

8/1/06: My Black Rouge arrived from Got Grit. Amazing since I only ordered it two or three days ago. I will use this once I get to the very final stages of figuring or to try and smooth out the surface.

8/11/06: I've done a bunch of work on the mirror. I made it pretty much worse and worse but now I've got it smoothed up for the most part. Still some work to do to get my TUE away. Yeah I know, I struggled with TDE for 14 hours now I'm going at it with TUE. I think the edge has something against me. Also did some work on the mounting, solved most of the problems encountered because I mounted my "truss" poles differently. But thatís fine with me, not to be mean, but anyone can take the measurements out of a book, cut it and screw it together, just "cut and paste". It's already done for them, not many personal touches; my scope will be quite unique. I put the side bearings on too. I made a cool modification to my foucault tester too! I took an old junky 6 X 20 finder scope and hooked it up so I can take readings through it! Everything is much bigger so it is much easier to make judgments. I am going to mount it on a hinge so I can swing it out of the way, use my eye for further adjustments, then just tilt it back up and it will be aligned throughout the whole test! This should make things much better and more accurate, it is a nice trade up from just the eye and before getting a whole camera system.

10/28/06: Well I got through more of the "learning curve" over the last 5 months which equates to about 5 hours of work on the mirror. The mirror has been staying rough the whole time. The lap got too thin to go on so a new one was made at the last ATM meeting. After much help from a friend I realized my stroke wasn't quite right and got many tips on strokes and pressing. Now the mirror is much smoother though the TUE is still there. Most certainly getting better though so hopefully (once again) a little work and I should be nice and spherical and ready to Parabolize! (again, once again). I haven't really worked all that much, some long brakes. But hopefully I am almost all the way back on track and ready to try and finish this thing up! (again, again, once again!) I got the new lap, mirror is almost spherical, and things are getting there.

12/4/06: Since I last updated I tried 2 more attempts at parabolizing. The first one ended in a flop, some more lessons learned. Then the second time I really was getting better. I woke up on the weekend and said to myself "I am going to finish my mirror this weekend". I really fell into my "nitch" and used everything I had learned and everything was going perfectly to plan. Every time I made a decision it worked out perfectly and just the way I had planned. Then when I got it to 1/6 Wave all I had to do was knock down the center a little bit and I would have had it. Well I got so nervous and things weren't working for me quite right so after two days which was hours and hours of work I ended up getting "tunnel vision" and just kept going and ended up over deepening the center quite a bit and basically just screwing the mirror up. It ended up being 1/2 Wave and way overcorrected. At the ATM meeting, with the help of all the great people down there (Hi Guys!) I sphereized my mirror in about 20 minutes and following the advice of my friends decided to go "all or nothing". A few more rounds to sphereize just a bit more and then 10 minutes straight parabolizing avoiding COC somewhat so the edge wouldn't get too much correction as it already had some. Lo and behold, 35 minutes later after having a fan blowing on the mirror the results were in, 1/11 wave!!! Woohoo!!! I'll wait till next meeting to be absolutely sure that the mirror is all the way cooled down and then my mirror should finally be done!!!!!!!!!!!!!!!!!! I also decided to rebuild the mount with some heavier 3/4" melamine coated board which slides against teflon great on its own. It came out MUCH better than my first attempt.

12/19/06: Well the ATM Meeting was yesterday and I finally got the moment of truth. MY MIRROR IS DONE!!! The results are even better then they were last week! The final results:

The mirror has a 1/12.5 Peak-Valley Wavefront Error Rating! Strehl Ratio is slightly above .98. The physical surface RMS error is 5.9nm. The overall correction is .042, with the perfect being .048, so my mirror is only .006 undercorrected. As general opinion goes if you must leave a mirror one way or the other Undercorrected is better than Overcorrected so my mirror is good in that respect also.

Beside the numbers, the overall mirror is very good. The edge is fairly good; there is a diffraction ring, though slightly dimmer on the right. The very last mm or two is turned slightly down, estimated to be about 1/15 wave or so. It is slightly accented by the fact that there is also an equally narrow high zone just inside it from where my TDE and TUE originally merged, just the tail end remnants of it. The surface is very smooth, only a very slight roughness/artifact detectable in the center, but it will be covered by the secondary. There was also no detectable astigmatism by the ronchi test.

So all in all if I do say so myself this is not only an excellent first mirror, but a very good mirror in itself! Here is the FigureXP file on my mirror:

I'll type up a little tear jerking conclusion to my first adventure in ATM'ing after I have first light. I'm a happy camper.

2/13/07: Well I picked up my mirrors yesterday at the ATM Meeting. The coating took a little while but my mirror looks GREAT! No sleeks or anything. I also got the Edmunds Scientific 6" F/8 recoated, being it is 40+ years old it has quite a few small sleeks, but they shouldn't hurt performance. All that is left to do it finish up the bearings, spray the inside of the tube black, which I might get a piece of sonotube that fits inside the wooden squares to help block stray light as my shroud came out kind of funky, but I will still have the structural rigidity of the wood and metal tubing. I also plan to get started on my second mirror at the next meeting, a 10" F/5!!! Yup, one done and another begun. I'll start a new page for that scope. I'll keep it much briefer than this whole page for my first mirror.

3/16/07: I decided against the sonotube as it adds weight and after a discussion on the ATM groups it seems my wooden OTA parts are *just* wide enough to keep stray light out of the focuser. You can check this by racking in your focuser all the way and strain looking to the side to see if you can see past either end of the tube, I just make it. I picked up 2 colors to paint the scope, a light sky blue and a darker navy blue. I am thinking up some cool paint jobs for this scope! I have finished sanding and filing everything down to my satisfaction for paint. I also wood puttied over screw holes that were countersunk enough to do so. I will make some paper patterns to aid with my fairly complex paint job, compared to single color. I also got some extra magic sliders, these seem to work fine by themselves against the wood bearings, I may just leave them as is. As soon as I paint the scope and silicon the mirror to the cell I am done! Just have to wait for a warm day. I might also add some other little do-dads like a finder, maybe a mirror cooling fan. At the last ATM meeting on the 13th (Tuesdays now) the group helped my pour a tile tool for hogging out my 10". This will probably be sacrificial, requiring another tool after hogging, but we thought it better to start with a full size tool. I'll be starting a new page for my 10" today!

3/25/07: It was finally warm enough so I went outside and did the base color of light blue. Soon I will do the second color in an outlining pattern I came up with. Then I just have to do the inside parts flat black. I think this scope is going to look pretty cool. I might just leave the base as is, or paint it to match the scope; I'll have to pickup some more paint.

3/30/07: I taped over most of the light blue and sprayed the dark blue to produce the pattern I wanted. It came out really great. I just have a few spots to touch up and then spray the inside flat black.

4/2/07: Well the scope itself is done being painted. I did the flat black and the whole OTA looks great. All I have to do it some misc. little parts and then the base, silicon the mirror on the cell and I'm ready to rock. I might also get some Protostar light flocking paper for across from the focuser just as an added touch.

4/14/07: I painted the base the light blue base color (no pun intended). Home depot has been out of the darker color I used to border the OTA so it may just stay this way, it looks really good, I cut three feet out of plywood for the ground board. I also painted the last of the the little parts like the mirror cell, part of the side bearings, and the ends of a few bolts. I re-attached the focuser and spider. I am really happy with how it came out.

4/15/07: I CAREFULLY glued the mirror to the cell. I am going to give it plenty of time to cure. After this the scope is ready for first light! I also ordered the Protostar Hi-tack flocking paper. It is a 20"X30" sheet that will easily cover the entire OTA visible through the eyepiece. Unfortunately, spring break ends tomorrow but I got a lot accomplished on this scope and the 10".

4/16/07: Even after 37 hours the silicon was just as soft and gooey as when I put it on. Clearly I need something else so I merely lifted the mirror off and wiped off the silicon from the back. Oh well, no harm done. 

4/19/07: I received the Protostar Hi-Tack Flocking. This stuff is GREAT! It is very dark and can be easily cut with scissors. If you miss-stick it you have to really pull to get it off but it comes off clean leaving the paint, not wrinkling and will stick just as well the next time you press it down. I put some on the tube wall opposite the focuser. I also attached the 3 wooden feet I cut to the ground board and permanently attached the magic sliders between the bottom board and ground board with the supplied sticky pads (these things really STICK). I reattached the spider which had to come out to put in the flocking. I am going to get some GE Clear Silicone II recommended by some experienced ATM for gluing the mirror to the cell.

4/27/07: I picked up another can of the dark blue paint needed. Home depot finally got it in. Silly me though, I forgot the silicone! Oh well I'll probably go back down that way within the week.

5/5/07: I finally got the silicone. I drilled the three support points right through on the cell with a small bit so the silicone can get squeezed into them and have a better hold. This silicone was fresh and came out very easily. I used a healthy amount and am going to give it plenty of time to dry. I think it will come out very good this time and soon I'll be ready for first light!

5/7/07: Well the silicone dried really fast but I wanted to give it some extra time. I also painted the last ouch on the scope, the dark blue border on the base. I cleaned each part with some paper towels to remove dust and little bits of wood dust and what not. I then did final assembly of the scope! I AM NOW READY FOR FIRST LIGHT! Sky is of course too hazy for me to want and do my first light so it will be tomorrow at the ATM Meeting!

5/8/07: Well first light was tonight at the ATM Meeting. THE VIEW IS ABSOLUTELY INCREDABLE!!! The Meeting was great. Almost all of the active members showed up and it was quite a show. For the first light report:

After 2 & 1/2 years of work it was great to see something, and even better, to see something really really nice! We viewed Venus and Saturn with Saturn stealing the show.

I only eyeballed the collimation with a collimation cap as the primary has no center mark yet.

Through regular plossls the views were very good. At 40X with my 25mm EP (Telescope FL is 990 MM, it's an F/6.5) Saturn was small, but tack on sharp with 3 moon visible. with my zoom EP at about 10MM and a 2X barlow (198X) the view was still right on when the seeing calmed down!

The real test and proof to me that this scope is great was Mike Linder was very kind and tossed his 7MM Nagler with a 2X power mate in for about 283X and you could see the Cassini Division along with one of the closer moons and some noticeable banding. When the seeing calmed intermittently the views were still very sharp. So this scope pretty much stands up to the old thumb rule of 50X per inch of aperture. I even held my digital camera up to the EP just for the heck of it and actually got a really nice image of Saturn! Albeit there was a slight ghost image above it from my hand moving.

Anyway, the point is, with the collimation just fairly close the views were tack on sharp even at high power with good contrast and the views simply blew me away. The scope has completely met my expectations.

I now consider this project officially DONE! Just a few odds and ends such as adding a center mark on the primary and stabilizing the pivot bolt with a second nut, along with putting some final stuff for it on my webpage.

I must say when I started this project long ago I never imagined the outcome would be so great. The largest part that helped me was meeting Matt and Gary Fuchs who introduced me at the ATM Meetings where I received much help from Gordon Waite and everyone else. I owe them all much. I am more than satisfied with this project and I think I have grown and learned in many ways since its start.

Many thanks again to Gordon and everyone!

Now it's back to polishing on the 10"

I was not the only one who was a site to see. Gary's Sheif gave some VERY sharp images of Saturn as well when I looked through it. Ken and Rob also completed their mirrors, Congratulations! Dave N also had a very cute little scope for his daughter that is completed or very near to it. Mike also brought his first scope which was very cool to look through. Gordon got some pictures of all the fun so I'll put some up here. All in all an *!AWSOME!* night with one of the largest attendances I've ever seen!

Congrats to all those people for their beautiful scopes and completed mirrors and once again thank you all for your input, help, and kind words.

A picture of everyone gathered around my scope. Unfortunately the wonderful host Gordon Waite was taking the picture and the one with him in it came out too blurry. (I'll get him when I bring my 10" down for first light)

In the brown shirt, center, is me with my hand on my beautiful new scope. To my left is my mother who is kind enough to drive me to the meetings (still too young). To her left is a new member, Ahmad. Far left is Henry whose 8" mirror is to his right. In the back behind the two is Steve who brought down his 16" for some design changes. Above my mom is Mike Linder who started out the ATM Meetings many years ago. To his left is Dave Nelson who was just completing a small scope for his daughter. Then in the back with the hat is Matt Fuchs who introduced me at the meetings. All the way to the right is his dad. In between them is Rob who also completed an 8" mirror that night. Between me and him and bending down is Herb who was fine grinding an 8". And kneeling below him is Ken who finished a 6" that night. There are a few other regulars at the meetings but this is most of them. Gordon Waite, the generous host took the picture and the ones with him in it came out too blurry. We'll get him on camera one of these days!

Of course also you get the first look at my beautiful new scope. It is your basic Dobson base riding on 3 magic sliders. The front is stiffened with a 1/2" plywood front board sprayed light blue like the rest of the scope. The rocker box is painted light blue with a border of darker blue. Same thing for each side of the two square upper and lower ends of the tube, connected with 1" square tubing. The side bearings also ride on magic sliders. The focuser is an Orion Basic Rack and Pinion with almost 2" of travel and the Spider inside is from Protostar with the 1/15 Wave diagonal from Antares. The inside (along with the part of the tubing facing inward as you can see) is sprayed flat black to reduce stay light and inside the upper box across from the focuser is Protostar Hi-Tack Flocking which reduces stay light by 99.9%. The motion is smooth in all directions and the balance is perfect with an eyepiece in. All in all a great scope!


Well it has been a long time since I started this scope and it is an immensely proud time. I am more than happy with the scope in every aspect. I thank Gordon Waite, my mother, and everyone at the ATM Meetings and on-line who helped me with this scope. I learned much about mirror making, scope building, and lessons I can apply to life. I have grown mentally a great deal (near infinite patience I'd say). ATM is a hobby I really really enjoy and it will be a part of me for the rest of my life. Anyway, I am happy, the scope is great, I thank all who have helped me, I learned a lot, and now it is onward and upward to ever better and bigger scopes. This project is DONE!!!

Now join me on my next project. A 10" F/5 !

The Earliest Setup of the "Shop" in My Basement. Below that you can see the Grinding Stand I later built.


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