Defibrillator III by Bob Keller
GemCad Ray Traces for RI = 1.76 Random Model Cosine Model ISO Model
Defibrillator III
Designed by Bob Keller December 2001A CAM Style Heart for 120 gears suitable for Spinel, Garnet, Corundum... Angles for R.I. = 1.76 55 facets + 19 facets on girdle = 74 1-fold mirror-image symmetry 120 index L/W = 1.012 T/W = 0.585 T/L = 0.578 P/W = 0.411 C/W = 0.145 H/W = (P+C)/W+0.02 = 0.576 P/H = 0.713 C/H = 0.252 Vol./W^3 = 0.182 Brightness at 0° tilt for RI = 1.76 COS = 72.3 ISO = 90.6
Pavilion cp 36.00 15-45-75-105 Cut to equal depth to establish center point 1 42.62 011-109 Cut facets 1-10 to centerpoint 2 43.60 013-107 3 43.91 015-105 4 43.58 019-101 5 42.86 021-099 6 39.59 029-091 7 37.69 037-083 8 37.00 045-075 9 40.21 057-063 10 41.27 060 g1 90.00 011-109 Set size, establish lower girdle line g2 90.00 013-107 Meet g1.1.2 g3 90.00 015-105 Meet g2.2.3 g4 90.00 019-101 Meet g3.3.4 g5 90.00 021-099 Meet g4.4.5 g6 90.00 029-091 Meet g5.5.6 g7 90.00 037-083 Meet g6.6.7 g8 90.00 045-075 Meet g7.7.8 g9 90.00 057-063 Meet g8.8.9 g10 90.00 060 Meet g9.9.10 Crown a 37.26 011-109 Match g1, establish upper girdle line b 38.73 013-107 Meet a.g1.g2 c 39.01 015-105 Meet b.g2.g3 d 38.89 019-101 Meet c.g3.g4 e 38.09 021-099 Meet d.g4.g5 f 35.13 029-091 Meet e.g5.g6 g 33.13 037-083 Meet f.g6.g7 h 32.50 045-075 Meet g.g7.g8 i 34.80 057-063 Meet h.g8.g9 j 37.76 060 Meet i.g9.g10 k 36.97 012-108 Meet g1.a.b.g2 l 36.34 017-103 Meet g3.c.d.g4 m 31.66 025-095 Meet g5.e.f.g6 n 28.32 041-079 Meet g7.g.h.g8 o 30.75 014-106 Meet k.b.c.l p 28.14 023-097 Meet l.d.e.m q 22.04 038-082 Meet m.f.g.n r 28.15 055-065 Meet n.h.i y 0.00 Table Meet k.a.a.k, o.l.p, p.m.q, others
The Defibrillator III Design File is available for GemCad users.
I designed Defibrillator III for a for a deep red pyrope garnet. This design is pretty bright as hearts go and is a good match for medium to deep saturated materials with RIs in the spinel-garnet-corundum range.
Begin the pavilion by carefully cutting four facets on indexes 15-45-75-105 at 36.00° to equal depth to establish a centered culet point. These four center point "finder" facets get cut away as pavilion facets 1-10 are subsequently cut to meet at this center point. The simple faceting in the "head" area on Defibrillator III should be facilitating if you are into vee notching your hearts.