2014-15 Stellafane Mirror Class
Session 7 held on 2015-Feb-21

At the Icy Fletcher House

It's been a very cold, snowy winter, and the Fletcher House is sporting a full set of icicles due to its sub-standard insulation. The club meeting scheduled for Dartmouth this evening was canceled due to snow across the Northeast (again). Turnout for mirror class was good, but not overwhelming, given the weather situation late in the day.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 At the Icy Fletcher House Fletcher House decked out in Icicles.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 At the Icy Fletcher House Bare roof = very bad insulation = lots of icicles.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 At the Icy Fletcher House The icicle in the right foreground is HUGE!

Grinding, Rough and Fine

Keith has started a second mirror, and is still using the coarse gray stuff; Katie and Tom have finished up using the fine white powders and have now moved on to polishing.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Grinding, Rough and Fine Keith grinds mid-day with #220 grit.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Grinding, Rough and Fine Tom is very fine grinding (see the white puddles on his stand) and pauses to check sagitta.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Grinding, Rough and Fine Katie is using a toothbrush to scrub here tool during a grit change.

Polishing

Of our 14 active students, we finished the day with 10 of them polishing (not all of the polishers were at class today).

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Polishing Ron cleans up his lap; Dory is to the left.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Polishing Dory's hands polishing here 6-inch mirror.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Polishing Michael is cleaning up a stand for Dory to work on.

Laps

Polishing requires Laps, and laps require TLC, such as pressing and trimming. We did that!

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Laps Ray and Katie in the basement; Katie is trimming her new lap.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Laps Getting ready for a warm press, Ron is warming his lap under the heat lamps.

Testing

Jay had his Ross Null Tester set up, and Dave had his double-pass knife-edge null tester set up, and testing was done.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Testing Jay's Ross Null Tester set up in the game room. The Ross Null lens is lying on its side in this shot.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Testing Ross Null testing in progress, the book is used to keep the Ross null lens at the proper distance as it is moved left or right for alignment.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Testing Dave's knife edge tester in single pass mode - the double pass perforated flat is not mounted at this time.

Lens Making

Rick and Ken worked on their 4.5=inch refractor doublets, although Ken was very careful to avoid being captured in a photo actually grinding.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Lens Making Rick is taping a lens element to a tool for support so he can work on the other side; he is chatting with Francis as he works.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Lens Making Ken is using a dial indicator to check the depth of his ear canal - you can't record too much quantitative data when making a lens! :-)

Professors of Glass

Ray and Jay, Professors of Glass, in their 'offices' at the back of the grinding room.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Professors of Glass Professor Ray checks his smart phone during a lull in the action.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Professors of Glass Read gave Professor Jay a fat envelope.

2014-15 Stellafane Mirror Class Session 7 held on 2015-Feb-21 Professors of Glass Professor Jay checks the envelope; Ken is using a 3-ball sphereometer to measure a lens element, he is using a spreadsheet on the computer to convert from sagitta to radius of curvature, and taking copious notes in his grinding log.