Butterfly Gores

Page 86

Butterfly Gores

Dimas Required: OD, OC Heel, Throat, Total

Side Lap, Total End Lap

Heel

Draw the working drawing

As with regular gore drawing cut metal to 1/2 OC

plus laps

Divide into 6 equal parts & transfer dimensions

from the working drawing.

Throat

Cut metal 1/2 OC + Lap & scribe cross hairs in the

center.

Set dividers to radius and place 1 time in the

center of crosshairs & scribe an arc on both sides

of the centre of the metal.

Place 1/2 the total throat on each side of the

center minimum 1/2” inch for band.

With dividers @ radius scribe arcs outward from

the 1/2 throat marks.

Add laps and flares as necessary.