PREFERRED

The solder connection has a completely rounded, continuous and smooth profile. No evidence of sharp edges, points, icicles, inclusions (foreign material) or wire strands. Insulation clearance is as close to the solder connection as possible without embedment.

NASA-STD-8739.3 [10.3]

PREFERRED

FLARED FLANGE (TERMINAL)

All edges of the terminal flange are completely covered with a continuous, smooth layer of solder to form a solder ball. The balled connection does not exceed specified height requirements.

Best Workmanship Practice

PREFERRED

INSULATION CLEARANCE

The insulation gap is minimal, with the insulation as close to the solder connection as practical without embedment or damage.

NASA-STD-8739.3 [9.1.1]

PREFERRED

THROUGH HOLE TERMINATION

All sharp edges of the component lead end are completely covered with a continuous, smooth, rounded layer of solder to form a solder ball. The balled connection does not exceed specified height requirements.

Best Workmanship Practice

ACCEPTABLE

INSULATION CLEARANCE (C)
(MAXIMUM)

The insulation gap (C) is less than two insulated wire diameters (D).

NASA-STD-8739.3 [9.1.2]

UNACCEPTABLE

IMPROPER INSULATION CLEARANCE (C)

The insulation gap (C) is greater than two insulated wire diameters, which may result in coronal formation and short circuits.

NASA-STD-8739.3 [9.1.2], [13.6.2.a.2]

ACCEPTABLE

INSULATION CLEARANCE (C)
(MINIMUM)

The insulation gap (C) is less than one insulated wire diameter (D), but is not embedded in the solder joint.

NASA-STD-8739.3 [9.1.1]

ACCEPTABLE

SOLDER CUP TERMINATIONS

The connection has an egg-shaped, spherical, or oval profile following the contour of the terminal and wire wrap. No evidence of sharp edges, points, icicles, inclusions (foreign material), or wire strands. Insulation clearance is acceptable.

NASA-STD-8739.3 [10.3]

ACCEPTABLE

UNUSED TERMINAL

All sharp edges of the terminal are completely covered with a smooth, continuous ball of solder.

Best Workmanship Practice

UNACCEPTABLE

UNUSED TERMINAL
NO SOLDER/PARTIAL SOLDER

All sharp edges of the terminal shall be completely covered with a smooth, continuous ball of solder.

Best Workmanship Practice

ACCEPTABLE

TERMINALS/WIRE LEAD

The connection has an egg-shaped, spherical or oval profile that follows the contour of the terminal and wire wrap. No evidence of sharp edges, points, icicles, inclusions (foreign material), or wire strands. Insulation clearance is acceptable.

NASA-STD-8739.3 [10.3]

UNACCEPTABLE

SHARP EDGES

The solder follows the contour of the terminal and wrap, BUT there is evidence of the sharp edge of the terminal protruding through the solder surface.

NASA-STD-8739.3 [10.3]

ACCEPTABLE

UNUSED SOLDER CUPS

The solder connection has an egg-shaped, spherical or oval profile. No evidence of sharp edges, points, icicles, inclusions (foreign material) or wire strands.

Best Workmanship Practice

UNACCEPTABLE

UNUSED TERMINAL, SHARP EDGES

The solder is continuous, BUT there is evidence of solder peaks, icicles or sharp turret edges protruding.

Best Workmanship Practice