PREFERRED

GENERAL REQUIREMENTS

The insulation jacket has been neatly trimmed, with no edge flash, smearing or damage. The conductor stranding lay (twist pattern) is undisturbed, and the conductor is undamaged.

ACCEPTABLE

THERMAL DISCOLORATION

Slight discoloration of the insulation jacket(s) at the trimmed edge is acceptable. Evidence of burning or charring is not acceptable.

NASA-STD-8739.3 [7.2.2]
NASA-STD-8739.4 [10.1.2], [19.6.1.a.1]

ACCEPTABLE

EDGE FLASH

Edge flash shall not exceed one-quarter insulated wire diameter (1/4 d.). Edge flash (as depicted) is considered normal, and should not contaminate or interfere with a crimped or soldered termination.

NASA-STD-8739.4 [10.1.6]

UNACCEPTABLE

EDGE FLASH/SMEARING

The edge flash is in excess of one-quarter insulated wire diameter (1/4 d.), and the stripped section exhibits smearing (melted insulation/film), which is considered a contaminant.

NASA-STD-8739.4 [10.1.6]

ACCEPTABLE

SCUFFED INSULATION/JACKET

Slight scuffing (a dull or rubbed appearance) of the insulation surface finish is acceptable, provided no other damage is evident.

NASA-STD-8739.3 [7.2.2]
NASA-STD-8739.4 [10.1.2]

UNACCEPTABLE

DAMAGED INSULATION/JACKET

The conductor insulation and/or cable jacket shall not exhibit any damage, such as nicks, cuts or charring. Conductors/Jackets exhibiting damage (other than minor scuffing) shall not be used.

NASA-STD-8739.3 [13.6.2.a.1]
NASA-STD-8739.4 [19.6.2.a.2]

UNACCEPTABLE

BURNED/CHARRED/PITTED INSULATION

Burned or charred insulation is the result of excessive heat application during the stripping process.

NASA-STD-8739.3 [6.6.1], [7.2.2], [13.6.2.a.1]
NASA-STD-8739.4 [6.6.1], [10.1.2], [19.6.2.a.1]

UNACCEPTABLE

BURNED/ETCHED STRANDS

Burned or etched strands are typically caused by current flow (leakage) between the thermal stripper blades, or as a result of stripping an energized conductor.

NASA-STD-8739.3 [6.6.2.b]
NASA-STD-8739.4 [19.6.2.a.2]