
Wire Wrapping 101
![]() | ![]() |
|---|
A "Regular" bit wraps the bare wire around the terminal. A "Modofied" bit wraps a portion of insulation around the terminal in addition to the bare wire.
This greatly increases the ability to withstand vibration.
A distinct advantage of wire wrapping is the ease with which a wire may be removed from a terminal to correct errors or modify wiring. An unwrap tool is
slipped over the terminal, engaging the first turn of the connection. While rotating the tool, the connection is removed in seconds, without damage to the terminal
There is a constant surveillance of manufacturing dimensions. Each wrapping bit is subjected to a series of "Qualification Tests". These consist of wrapping
groups of wire on various types of terminals. The wrapped wires are then subjected to a "strip" test to determine adequate tightness. "Unwrap" tests are also performed
to ensure against an "Over Tight" wrap.
Solid wire is used for wire wrapped connections, and Copper is the most commonly used type. Minimum elongation of 15% is required for 24 through 32 AWG: 20% for larger wire.
Wire Size Chart
| Bare Wire Dia. (in) | Bare Wire Dia. (mm) | AWG (USA) | SWG (GB) |
|---|---|---|---|
| .0403 | 1.022 | 18 | - |
| .040 | 1.016 | - | 19 |
| .036 | 0.914 | 19 | 20 |
| .032 | 0.813 | 20 | 21 |
| .028 | 0.711 | 21 | 22 |
| .0253 | 0.643 | 22 | - |
| .024 | 0.61 | - | 23 |
| .0226 | 0.574 | 23 | - |
| .022 | 0.559 | - | 24 |
| .0201 | 0.51 | 24 | - |
| .0020 | 0.508 | - | 25 |
| .018 | 0.457 | - | 26 |
| .0179 | 0.455 | 25 | - |
| .0164 | 0.417 | - | 27 |
| .0159 | 0.404 | 26 | - |
| .0148 | 0.376 | - | 28 |
| .0142 | 0.361 | 27 | - |
| .0136 | 0.345 | - | 29 |
| .0126 | 0.320 | 28 | - |
| .0124 | 0.315 | - | 30 |
| .0116 | 0.295 | - | 31 |
| .0113 | 0.287 | 29 | - |
| .0108 | 0.274 | - | 32 |
| .0100 | 0.254 | 30 | 33 |
| .0092 | 0.234 | - | 34 |
| .0089 | 0.225 | 31 | - |
| .0084 | 0.213 | - | 35 |
| .0008 | 0.203 | 32 | - |
Five Steps to Make A
Wire Wrap Connection

"Strip" Force Chart
| Wire AWG | Wire Dia. (in) | Wire Dia. (mm) | Min # Turns Bare Wire | Min Strip Force (lbs.) | Min Strip Force (g) |
|---|---|---|---|---|---|
| 16 | .0510 | 1.30 | 4 | 15 | 6800 |
| 18 | .0403 | 1.00 | 4 | 15 | 6800 |
| 20 | .0320 | 0.80 | 5 | 8 | 3600 |
| 22 | .0253 | 0.65 | 5 | 8 | 3600 |
| 24 | .0201 | 0.50 | 6 | 7 | 3200 |
| 26 | .0159 | 0.40 | 7 | 6 | 2700 |
| 28 | .0126 | 0.32 | 7 | 5 | 2200 |
| 30 | .0100 | 0.25 | 7 | 3.3 | 1500 |
Terminal Diagonal Chart
| In. mm |
.010 0.25 |
.015 0.38 |
.020 0.51 |
.025 0.64 |
.030 0.76 |
.035 0.89 |
.040 1.02 |
.045 1.14 |
.050 1.27 |
.055 1.40 |
.060 1.52 |
.065 1.65 |
.070 1.78 |
.075 1.91 |
.080 2.03 |
.085 2.16 |
.090 2.29 |
.095 2.41 |
.100 2.54 |
| .010 0.25 |
.014 0.36 |
.018 0.46 |
.022 0.56 |
.027 0.69 |
.032 0.81 |
.036 0.91 |
.041 1.04 |
.046 1.17 |
.051 1.30 |
.056 1.42 |
.061 1.55 |
.066 1.68 |
.071 1.80 |
.076 1.93 |
.081 2.06 |
.086 2.18 |
.091 2.31 |
.096 2.44 |
.101 2.57 |
| .015 0.38 |
.018 0.46 |
.021 0.53 |
.025 0.64 |
.029 0.74 |
.033 0.84 |
.038 0.97 |
.043 1.09 |
.047 1.19 |
.052 1.32 |
.057 1.45 |
.062 1.58 |
.067 1.70 |
.072 1.83 |
.077 1.96 |
.082 2.08 |
.087 2.21 |
.092 2.34 |
.097 2.46 |
.102 2.59 |
| .020 0.51 |
.022 0.56 |
.025 0.64 |
.028 0.71 |
.032 0.81 |
.036 0.91 |
.040 1.02 |
.045 1.14 |
.049 1.25 |
.053 1.35 |
.058 1.47 |
.063 1.60 |
.068 1.73 |
.073 1.85 |
.078 1.98 |
.083 2.11 |
.088 2.24 |
.093 2.36 |
.098 2.49 |
.103 2.62 |
| .025 0.64 |
.027 0.69 |
.029 0.74 |
.032 0.81 |
.035 0.89 |
.039 0.99 |
.043 1.09 |
.047 1.19 |
.050 1.27 |
.056 1.42 |
.060 1.52 |
.065 1.65 |
.069 1.75 |
.074 1.88 |
.079 2.01 |
.084 2.13 |
.089 2.26 |
.094 2.39 |
.099 2.52 |
.104 2.64 |
| .030 0.76 |
.032 0.81 |
.033 0.84 |
.036 0.91 |
.039 0.99 |
.042 1.07 |
.046 1.17 |
.050 1.27 |
.054 1.37 |
.058 1.47 |
.062 1.58 |
.067 1.70 |
.071 1.80 |
.076 1.93 |
.080 2.03 |
.085 2.16 |
.090 2.29 |
.095 2.41 |
.100 2.54 |
.105 2.67 |
| .035 0.89 |
.036 0.91 |
.038 0.97 |
.040 1.02 |
.043 1.09 |
.046 1.17 |
.049 1.25 |
.052 1.32 |
.056 1.42 |
.060 1.52 |
.064 1.63 |
.069 1.75 |
.073 1.85 |
.078 1.98 |
.082 2.08 |
.087 2.21 |
.091 2.31 |
.096 2.44 |
.101 2.57 |
.106 2.69 |
| .040 1.02 |
.041 1.04 |
.043 1.09 |
.045 1.14 |
.047 1.19 |
.050 1.27 |
.052 1.32 |
.056 1.42 |
.060 1.52 |
.064 1.63 |
.068 1.73 |
.072 1.83 |
.076 1.93 |
.080 2.03 |
.084 2.13 |
.089 2.26 |
.092 2.34 |
.097 2.46 |
.102 2.59 |
.107 2.72 |
| .045 1.14 |
.046 1.17 |
.047 1.19 |
.049 1.25 |
.050 1.27 |
.054 1.37 |
.056 1.42 |
.060 1.52 |
.063 1.60 |
.067 1.70 |
.071 1.80 |
.074 1.88 |
.078 1.98 |
.083 2.11 |
.087 2.21 |
.091 2.31 |
.096 2.44 |
.101 2.57 |
.105 2.67 |
.109 2.77 |
| .050 1.27 |
.051 1.30 |
.052 1.31 |
.053 1.35 |
.056 1.42 |
.058 1.47 |
.060 1.52 |
.064 1.63 |
.067 1.70 |
.071 1.80 |
.074 1.88 |
.078 1.98 |
.082 2.08 |
.086 2.18 |
.090 2.29 |
.094 2.39 |
.098 2.49 |
.103 2.62 |
.107 2.72 |
.111 2.82 |