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  #81  
Old 16-05-2018, 08:06 PM
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Lognic04 (Logan)
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I ran out of 80 grit! the ring is VERY nearly gone - about 1.5mm left. Not sure what the best thing to do here is? Switch to fine grit?
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  #82  
Old 16-05-2018, 10:31 PM
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Originally Posted by Lognic04 View Post
I ran out of 80 grit! the ring is VERY nearly gone - about 1.5mm left. Not sure what the best thing to do here is? Switch to fine grit?
I suggest you take a break and get more 80 grit on Saturday. Progress will be slower with 120.

Rod
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  #83  
Old 17-05-2018, 07:55 AM
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I suggest you take a break and get more 80 grit on Saturday. Progress will be slower with 120.

Rod
Hi Rod, I think that I am so close to it being done that after a few 120 wets it will be spherical - the ring is only about 2mm big now anyway.
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  #84  
Old 17-05-2018, 07:02 PM
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Switched to 120 grit now, and the ring is near gone. Boy, was that an ordeal to clean up all the 80 grit mess!
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  #85  
Old 19-05-2018, 10:28 PM
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Caught up with everyone today at the IMS! While I was there, i got the mirror and tool mated perfectly, and now it just needs a few more wets to finally spherise it and then on to 320 and finer!
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  #86  
Old Yesterday, 11:12 AM
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Lognic04 (Logan)
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I did a few more 120 grit wets, used an eyepiece as a magnifier and can confirm that there are no 80 pits left! On to 320 grit, as i dont have 240.
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  #87  
Old Yesterday, 12:42 PM
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Looking for pits after 120 grit!
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  #88  
Old Yesterday, 03:48 PM
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Grr, just finished a wet only to find quite a few bad scratches!!!
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  #89  
Old Yesterday, 04:53 PM
Billyboy78 (Bill)
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Make sure you maintain a nicely rounded chamfer around the edge of tool and the mirror. When stopping you move the tool 3/4 of the way off then lift it up, leaving the edge of the tool on the mirror.......SCRATCH.
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  #90  
Old Yesterday, 05:30 PM
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Grr, just finished a wet only to find quite a few bad scratches!!!
Hi Logan

Frustrating I know! But at least it's right at the beginning of a finer grade abrasive. A couple of wets at 120 will remove them quickly. You might even be able to grind them out at 320 but I think you'll find it quicker with 120.

Bill is right. Be careful how you lift the mirror off the tool. When you start a wet, gently place the mirror or tool on top and make a few very short strokes with no pressure. This helps reduce the size of any larger bits of grit.

Scratches look ugly but even if you have a few on your mirror at then end they make almost no difference to its performance. I would get rid of these since you are only just out of rough grinding but if I had a couple at the end of fine grinding, I would just leave them.

Rod
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  #91  
Old Yesterday, 07:19 PM
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Lognic04 (Logan)
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Thanks guys - how should i be taking the mirror off safely?
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