Defibrillator III  by Bob Keller
GemCad Ray Traces for RI = 1.760
Random Model Cosine Model ISO Model
Defibrillator III
Designed by Bob Keller December 2001, Revised April 2015
A CAM Style Heart for 120 gears suitable for Spinel, Garnet, Corundum...
Angles for R.I. = 1.76055 + 19 girdles = 74 facets
1-fold mirror-image symmetry120 index
L/W = 1.012 T/W = 0.583 U/W = 0.528 P/W = 0.411 C/W = 0.146
Vol./W^3 = 0.184Brightness at 0° tilt for RI = 1.76 COS = 72.3 ISO = 90.6
Pavilion
cp36.0015-45-75-105Cut to equal depth to establish center point
142.62011-109Cut facets 1-10 to centerpoint
243.60013-107 
343.91015-105 
443.58019-101 
542.86021-099 
639.59029-091 
737.69037-083 
837.00045-075 
940.21 057-063 
1041.27060 
g190.00011-109Set size, establish lower girdle line
g290.00013-107Meet g1.1.2
g390.00015-105Meet g2.2.3
g490.00019-101Meet g3.3.4
g590.00021-099Meet g4.4.5
g690.00029-091Meet g5.5.6
g790.00037-083Meet g6.6.7
g890.00045-075Meet g7.7.8
g990.00057-063Meet g8.8.9
g1090.00060Meet g9.9.10
Crown
a37.26°011-109Match g1, establish upper girdle line
b38.68°013-107Meet a.g1.g2
c38.92°015-105Meet b.g2.g3
d38.82°019-101Meet c.g3.g4
e38.06°021-099Meet d.g4.g5
f35.10°029-091Meet e.g5.g6
g33.10°037-083Meet f.g6.g7
h32.54°045-075Meet g.g7.g8
i34.77°057-063Meet h.g8.g9
j37.69°060Meet i.g9.g10
k36.96°012-108Meet g1.a.b.g2
l36.25°017-103Meet g3.c.d.g4
m31.54°025-095Meet g5.e.f.g6
n28.18°041-079Meet g7.g.h.g8
o30.72°014-106Meet k.b.c.l, k.a.a.k
p28.20°023-097Meet l.d.e.m
q22.18°038-082Meet m.f.g.n
r28.43°055-065Meet n.h.i, i.j.i
t 0.00°TableMeet k.a.a.k, o.l.p, p.m.q, others

Download PDF format printer friendly cutting instructions: [ Download Icon Defibrillator III Printer Icon ]

Download the GemCad format design file: [ Download Icon defib3.gem ]

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.


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Bob Keller