Wiring an instrument panel

[Yenn]

I have seen a panel on telescoping arms. Very nice, but there is a lot of extra weight involved. Sadly we cannot ask the pilot how it really works for him as it crashed and he is no longer with us. It was said by RAAus at one stage that the plane broke up, but I don't know if that was the final outcome. Could extra weight have been a factor, tha engine was heavier than standard.

 

 

[danny_galaga]

About colour coding. For me what it meant as an auto electrician is that if you look at one end of the wire and see it is pink, then you look for pink somewhere else if you are tracing a fault. You don't need to memorise any codes. If one the back of your tacho, there is is a green wire, an orange wire and a blue wire thats the colours you will be looking for elsewhere. It's always possible something else has that colour but then maybe you are looking at a couple of blue wires, instead of thirty white ones!

 

 

[Jaba-who]

About colour coding. For me what it meant as an auto electrician is that if you look at one end of the wire and see it is pink, then you look for pink somewhere else if you are tracing a fault. You don't need to memorise any codes. If one the back of your tacho, there is is a green wire, an orange wire and a blue wire thats the colours you will be looking for elsewhere. It's always possible something else has that colour but then maybe you are looking at a couple of blue wires, instead of thirty white ones!

Yeah. Makes it a hell of a lot easier. 

The trouble I’ve run into each time I’ve rewired my panel is that I’ve added more and more wires so have had to double up on colours and I still have a lot of plain white wires. (on my 4th panel in 12 years - every time I’ve added some new you-beaut  device I’ve had to rewire the whole lot) 

 

ive found the other biggest useful thing is the computer printed label at each end of the wire under clear heat shrink. 

 

 

[Jaba-who]

I have seen a panel on telescoping arms. Very nice, but there is a lot of extra weight involved. Sadly we cannot ask the pilot how it really works for him as it crashed and he is no longer with us. It was said by RAAus at one stage that the plane broke up, but I don't know if that was the final outcome. Could extra weight have been a factor, tha engine was heavier than standard.

Mine is not heavy. 

Consists of two lengths of aluminium tubing ( about 30 cm long) fixed to the inside of the dash housing under saddle clamps.

 

And then two bits of tubing that telescope into them. These are fixed to a short bit of channel section aluminium that is pop riveted to the dash panel. The bolt joining them provides pivot action to tilt the panel. 

 

When pulled out there a couple of spring loaded pins that drop into holes to stop the moving tubes  falling out the end of the static tubes. Total weight would be about 30 or 40 grams I’d guess. 

 

 

[skippydiesel]

I have used a Dymo labeller and 8 point font to make ID tags. Takes the worry out of poor penmanship. The wire need to be wiped over with metho to clean off any oily residue before the label is put on and then covered with clear heat shring.

Hi OME - like you I have used a labeller however have found that one draw back - the paper is heat sensitive ( this is how it prints) so will turn black if subject to even slightly elevated temperatures.

 

 

[skippydiesel]

As a long time bush mechanic, I have two 12 volt wiring advice suggestions, that have stood me well for longer than I care to mention -

 

• Take extra care with your earth (-) return circuit. It will pay of in reliability and longevity of instruments/systems. Do not rely on chassis/fuselage earth return - run a dedicated earth wire back to the battery Negative terminal.
   
   
  
• Where ever possible, reduce the number of connections (every connection is a potential failure point) and make sure all connections are tight.
   
   
  

 

 

 

 

[cscotthendry]

I'll second Skippydiesel's post. I was wondering if someone was going to eventually bring up the grounds issue. Being an auto electrician, don't be tempted to follow auto wiring practice of using the frame as the return electrical path. That is just asking for trouble. Get yourself a big heavy bus bar with lots of screw terminal points, connect a nice heavy cable to it from the battery and connect the ground from EVERY piece of equipment back to that bar. If you do that without exception, you'll likely have a lot fewer electrical issues.

 

Do not be tempted to shortcut this to save a bit of wire or work.

 

 

[danny_galaga]

Good point guys. I probably would have done it that way anyway because the distance from the panel to the battery is so short and also the circuit otherwise would be through several aluminium tubes bolted together. That would just be asking for trouble. Not just electrically but potentially structurally as well

 

 

[nanggala]

i need schema diagram Becker AR 4201-O or Service Manual

 

 

[CAVU Mark]

AC 43.13 from the FAA, use aviation ring terminals, and a computer to generate small wiring labels attached with clear heat shrink.

 

 

[cherk]

i need schema diagram Becker AR 4201-O or Service Manual

TRY : BECKER AR 4201 INSTALLATION AND OPERATION MANUAL Pdf Download.

 

 

[eightyknots]

Mine is not heavy. Consists of two lengths of aluminium tubing ( about 30 cm long) fixed to the inside of the dash housing under saddle clamps.

 

And then two bits of tubing that telescope into them. These are fixed to a short bit of channel section aluminium that is pop riveted to the dash panel. The bolt joining them provides pivot action to tilt the panel.

 

When pulled out there a couple of spring loaded pins that drop into holes to stop the moving tubes falling out the end of the static tubes. Total weight would be about 30 or 40 grams I’d guess.

Would you happen to have a picture of this?

 

 

[Jaba-who]

 

Would you happen to have a picture of this?

This is an original picture when I first made it and tried it out.

 

The telescopic bit is simply two bits of aluminium tubing that one inserts into the other.

 

The internal shape of the Jabiru panel surround lender itself easily to fixing the outer static tube to the ridged flat inner surface.

 

This photo was a trial with simple plastic saddles holding the tubing in place. I subsequently replaced it with metal saddles. ( not aviation quality I have to admit. I couldn't get anything in aviation aluminium of the size to match the tubing but made the considered judgement that it was not going to be stressed or anything in use so was of no safety consideration that they weren't aviation quality.

 

What you can't see is the two small brackets that join the rear of dash panel to the inner mobile slide tube. Essentially each is just a small section of channel just wide enough to fit across the end to tube and held in place with a single through bolt - allows it to pivot/rotate forward and downward to allow the dash panel to tilt forward to allow access to the back of the panel.

 

The front face of the bracket is pop riveted to the back of the panel.

 

I fabricated a small spring loaded pin housed in a folded metal cage - the pin drops into a hole in the inner tube to prevent the inner tube pulling out all the way and dropping the dash panel into your lap. In the end it was not really needed because once you connect a few cables to the instruments you start to limit its travel anyway.

 

 

[eightyknots]

[ATTACH=full]61633[/ATTACH]

This is an original picture when I first made it and tried it out.

 

The telescopic bit is simply two bits of aluminium tubing that one inserts into the other.

 

The internal shape of the Jabiru panel surround lender itself easily to fixing the outer static tube to the ridged flat inner surface.

 

This photo was a trial with simple plastic saddles holding the tubing in place. I subsequently replaced it with metal saddles. ( not aviation quality I have to admit. I couldn't get anything in aviation aluminium of the size to match the tubing but made the considered judgement that it was not going to be stressed or anything in use so was of no safety consideration that they weren't aviation quality.

 

What you can't see is the two small brackets that join the rear of dash panel to the inner mobile slide tube. Essentially each is just a small section of channel just wide enough to fit across the end to tube and held in place with a single through bolt - allows it to pivot/rotate forward and downward to allow the dash panel to tilt forward to allow access to the back of the panel.

 

The front face of the bracket is pop riveted to the back of the panel.

 

I fabricated a small spring loaded pin housed in a folded metal cage - the pin drops into a hole in the inner tube to prevent the inner tube pulling out all the way and dropping the dash panel into your lap. In the end it was not really needed because once you connect a few cables to the instruments you start to limit its travel anyway.

I like it. Very practical!

 

 

[Yenn]

I have a rectangular panel mounted within the centre of the panel. A piano hinge at the bottom and 2 screws hold it in place. I can undo the two screws and hinge it down or then remove the piano wire in the hinge and pull the centre part out.

 

 

[danny_galaga]

Getting to the pointy end of actually wiring up the panel. Only missing a radio and airspeed. the airspeed has no electrical so thats not a worry. radio is expensive so for now waiting until later. since im 2 weeks leave i gathering bits now. this:

 

http://www.flight-mechanic.com/wp-content/uploads/2017/11/9-116.jpg

 

looks like a handy guide for wire size. what are my best bets iin Australia, but particularly Brisbane of getting wire? And I guess crimp terminals and a reasonable pair of crimp pliers?

[Blueadventures]

a lot of my dymo labels have faded, coloured wiring make sense, its easy as heck to trace.

Pencil graphite doesn’t fade over time.

[Blueadventures]

Getting to the pointy end of actually wiring up the panel. Only missing a radio and airspeed. the airspeed has no electrical so thats not a worry. radio is expensive so for now waiting until later. since im 2 weeks leave i gathering bits now. this:

 

http://www.flight-mechanic.com/wp-content/uploads/2017/11/9-116.jpg

 

looks like a handy guide for wire size. what are my best bets iin Australia, but particularly Brisbane of getting wire? And I guess crimp terminals and a reasonable pair of crimp pliers?

This sites shop sells wire, also asap at Caboolture would sell it. Multi core is needed for radio harness. I expect with your trade you will have coded the wiring. I also used some different colours for some circuits so I can easily follow whenever trouble shooting a fault. And have a copy of the wiring diagram on board as a reference when needed. I have 3 ground posts, being tube construction uses insulated Parts clamps and metal threads as the post, one at convenient locations inside panel and one behind the seats. Posts some images when you can, how long till you do taxi runs and where will you be based. Look forward to catching up at a flyin and saying hi. If you chasing some lengths of colour tefzel wire let me know and I may have some spare I can post. Cheers

[danny_galaga]

This sites shop sells wire, also asap at Caboolture would sell it. Multi core is needed for radio harness. I expect with your trade you will have coded the wiring. I also used some different colours for some circuits so I can easily follow whenever trouble shooting a fault. And have a copy of the wiring diagram on board as a reference when needed. I have 3 ground posts, being tube construction uses insulated Parts clamps and metal threads as the post, one at convenient locations inside panel and one behind the seats. Posts some images when you can, how long till you do taxi runs and where will you be based. Look forward to catching up at a flyin and saying hi. If you chasing some lengths of colour tefzel wire let me know and I may have some spare I can post. Cheers

 

Thanks, have contacted asap.

[440032]

Get some of this. Every workshop should have some.

[danny_galaga]

Get some of this. Every workshop should have some.

Yes, Lucas sold a LOT of harness smoke back in the day :D

[M61A1]

Get some of this. Every workshop should have some.

Sir Joseph Lucas.....Prince of Darkness.....

[Bruce Tuncks]

On my panel, I ran the wires to each instrument with no joiners. I reckon this made the wiring look messy but it did avoid a possible point of unreliability in the joining plugs. Has anybody used plugs?

[Yenn]

I use plugs so that the panel can be removed for servicing. No problems there, I did have a problem with the earth being undersized, but luckily I spotted that it had overheated, before it gave way.

[facthunter]

Your throttle cable can make a bad alternative if your earthing is not up to it. Nev