Tools and Techniques. Paul Kuntz. February 16, 2013

Transcription

1 Homebuilt Aircraft Wiring Tools and Techniques Paul Kuntz EAA 430 February 16,

2 AeroElectric Connection Join the aircraft electric discussion forum, hosted on matronics.com list/ moderator is Bob Nuckolls Get a copy of Bob Nuckolls book, The AeroElectric Connection, free as a PDF file from his web site Now at 12 th edition or print copy for $20.00 plus $3.00 postage 2

3 Wire Aircraft grade wire Color convention: Red/Black Current to device White Current from device to ground Green ground, not carrying current Tefzel insulation tough, heattolerant, remains flexible for a very long time 19 individual strands, copper, each strand tinned. Withstands vibration Solders well 20 ga wire will carry 7 amps with 10 deg C temperature rise. No need to go smaller. Resistance 10 ohms/1000 ft (10 ft length =.01 ohms;.05 V drop at 5 amps) 14 ga 15 amps 12 ga 22 amps 4 ga 72 amps 2 ga 100 amps For starter currents, use welding wire (small strands, very flexible) 3

4 Soldering Hakko 936 soldering station shown The pros swear by Metcal expensive new, but affordable on ebay. Uses radio frequency power to heat only the tip. Use 63/37 lead/tin solder (eutectic), not 60/40. Soldering station, Portable propane iron 4

5 Soldering Soldering station, Portable propane iron With clothespins and instant glue, assemble simple jigs in a few seconds 5

6 Wire Stripping & Solder Splicing This type Not this type 6

7 Wire Stripping & Solder Splicing Don t forget the heat shrink! 7

8 Pre Insulated Diamond Grip (PIDG or Fast on) Terminals Lots of options 8

9 PIDG (Fast on) Terminals Aircraft grade terminals grip the insulation as well as the wire, for strain relief. Don t use the automotive type! Fold end of small gauge wire for tight crimp in terminal 9

10 Knife Splices & Butt Splices Could be used for joins at wing root, but for the few times you ll be taking the wings off, just put a service loop in the wire, cut it and splice it when necessary. 10

11 Wire Labels 11

12 Molex or AMP Mate N Lock Connecters 12

13 Molex Connecters 13

14 Molex Connecters removal tool closes the barbs so that you can remove the connector 14 from the housing

15 D sub Connecters Commonly available in crimped or soldered stamped sheet metal, but get the machined gold plated type. 15

16 D sub Connecters For small gauge wire, fold the end back, insertfolded endinthe terminal and crimp 16

17 D sub Connecters Pin insertion and removal tool Insertion rarely requires the tool For removal, insert from wire end, grasp tool and wire, then extract 17

18 Shielded Wire 18

19 Shielded Wire 19

20 RG 400 Coax Suitable for VHF radio and transponder RG 400 superior to RG 58 in every way Observe bend radius. If you kink it, throw it away 20

21 Avionics Ground Bus Note multiple wires to firewall ground for ample current capacity. Each pin can carry 5 amps. Eliminate ground loops and associated hard to identify avionics noise issues by grounding all 21 avionics at a common point that collects all of the ground wires from avionics components.

22 D Sub pins as in line connectors 22

23 Thermocouples Thermocouples work by measuring very small voltages generated at the junction of dissimilar metals. So, every joint in the wire is another dissimilar metal junction. Therefore, make all junctions with the same type pin and same junction type (soldered, crimped). Minimize connections and keep junction pairs at the same temperature. 23

24 Fuses vs. Circuit Breakers No glass fuses! Fuses open at least as quickly as circuit breakers. Fuses are simple, robust and extremely reliable. You can t reset a fuse, but resetting a breaker in flight is a questionable practice. 24

25 In Line Fuses 25

26 Weather Proof Connectors Seal All connectors available from Aircraft Spruce Use B crimp type connectors similar to Molex 26

27 Wire Ties, Anchors, Lacing Thomas & Betts wire ties have a metal locking tab and are rated to 185 deg F 27

28 Wire Ties, Anchors, Lacing 28

29 Panel Legends Brother p touch label printer Label tapes available in various widths, tape colors, character colors Examples are white letters on clear tape. 29

30 Bench Power Supply Provides DC power at regulated 13.8 V, emulating the alternator output for testing avionics and wiring on the workbench or in your plane. 30

31 Web Sites list/ t / il li t/ start there and join the AeroElectric List. t Participation is by through aeroelectric list@matronics.com Bob Nuckolls homebuilt aircraft electrical system design and techniques useful reference cocuments p// / / many short articles on a variety of techniques info/soldering tip videos Soldering tips and short videos A comprehensive source of electrical parts & supplies Source for wire, coax, fuses, switches, terminal, etc. supplies.aspx variety of electrical supplies & tools Likely to have just about anything you need, but the web site makes it nearly impossible to find what you are looking for, unless you are a professional parts buyer. I bought a few things here, after exhausting other resources. 31