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Refractor Interest Group

Optical Designers
Dick Parker, Rick Hunter & Paul Valleli work on the lens design of Rick's refractor at the January 2010 mirror class.
Designing a Refractor

The Refractor Interest Group, or RIG, was formed by Paul Valleli in March 2008. Several members have been working on making their first refractor under the guidance of Paul and Dick Parker. Bert Willard contributed to the optical design using OSLO, and Dick has been hosting work sessions in his basement which has been christened 'Refractorville' (he has made several refractors quite successfully).

Dick Parker with Refractor
Dick Parker with his completed RIG Refractor in November 2009
Dick with his refractor

Participating members include Jim Ericson, Rick Hunter, Ray Morits, Ken Slater and Dave Tabor.

Remers Book

Using optical glass donated to the club by Paul, the baseline design is for a 4½-inch f/15 oiled refractor made from K5 and SF1 (Rick is using different glass and a slightly different design). At Paul's recommendation, we are using Norman Remer's book for reference.

Dick Parker has made several refractors, and he wasted no time in completing one based on the RIG design. The photo at left shows him with an optically complete but unpainted tube of his refractor in November 2009.

In the photos below, you will see Dick Parker's shop, filled with dozens of grinding barrels. Besides being a member of Stellafane, Dick is also a member of the Astronomical Society of Greater Hartford, and runs a mirror class for them, which is why he has so many grinding stands in his basement. Our Stellafane RIG group has found it to be a pleasant retreat to work on refractor lenses in the winter.

Photos from a RIG work session at 'Refractorville' (Dick's workshop) in January 2011

Dick's Shop
Jay, Dick and Ray in Dick's shop, before work begins.
Lens Cell
Rick examines Dick's lens cell, Jay (and hidden Ray) at right.
Radius Rods
At Ken's request, Dick demonstrated how radius rods are used. Dave and Ray are taking it all in.
Dave Tabor
Dave prepares to grind, Rick is looking at something in his hands in the background.
Ken Slater
Ken grinds the flint's R3.
Jay Drew
Jay was there working on a mirror, and Alan Hall is in the background working on a lens.

Photos from a RIG work session at 'Refractorville' (Dick's workshop) in January 2012 (Tall photos by Tom Parker):

Rick Measures
Rick zeroes his ring sphereomter on a flat piece of glass.
Ray Grinds
Ray is grinding his crown.
Ken's Glass
Ken's glass. The flint is taped to tool R3. Plate glass tool for R4 is on the right, before R4 grinding has started.
Ken Records
Ken records the sagitta of the flint's R4.
Rick Grinds
Rick begins a new wet.
Watching Football
Near the end of the day, the TV came out to watch the Patriots beat the Ravens in the division playoff game.

From time-to-time we will add photos and information to this page as work progress.

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