MainePorsche

Black silicon tape Part# 3929 pegasusautoracing.com
PS - Once found black silicon tape at a local NAPA store.

danglerb

I've seen high current reflow a soldered connection. I guess you could argue it wasn't proper, but there would be no issue with a crimp.

Podguy

Sure there would be an issue with a crimp if the connection gets hot enough to melt solder. Unless you are using teflon insulated wiring the insulation will catch in fire.

Someone mentioned a soldered joint being destroyed by the flux. If you use acid core solder then it will eat into the wiring. Acid core is for plumbing. Rosin core solder is for electrial work and will NOT corrode the wiring!

There is a danger to soldering. With too much heat the solder can flow down the wire under the insulation and become brittle. With some vibration what was a felxible wire becomes solid and subject to breaking.

Even with household wiring I have chased down more than one wire nut that has become corroded from a loose connection and no longer works.

blown 87

Crimps are bad at getting resistance on them, which is one of a couple of ways a soldered joint will get hot, to much current or resistance.

WallyP

"If you want some quality silicon tape to wrap your harnesses, here's the same stuff we use at work for a fraction of the price elsewhere. Probably stolen.

http://www.ebay.com/itm/160582636756...#ht_1104wt_956 "

I don't know how low they will go, but they accepted my offer of $10/roll for two rolls...


Wire connections are very rarely soldered on aircraft - crimped with insulated sleeves is the standard method of splicing. Good enough for me.

blown 87

Correct, but it has more to do with most wires on aircraft being Aluminum than anything else, also a solder connection does not have the vibration resistance that a crimped does.

The real problem with most crimps is that they are done wrong.
We have a 928 in the shop now that has a intermitiant problem with a aftermarket radio, and I got 500 bucks that says it is going to be a crimped connection that is the problem.


Just out of curiosity, how many of you folks that talk about doing work on aircraft have a A&P license?

Maleficio

You keep talking about a crimp being made wrong. What can be done wrongly with crimping a metal barrel onto a wire end? Are you referring to those crazy plastic crimps that fold up and snap into place?

I don't have an A&P license, only Navy electrical training. Would A&P training show me another way to repair wires in an aircraft?

Mother

I do with IA assigned by repair station (Inspector Authorization) and I can crimp badly and solder badly also.

blown 87

Cool, what kind of aircraft you work on?
I also have a A&P, but no IA.

PS, I hear you about crimping and soldering badly, my own work is how I know what bad ones look and act like at times......................

Mother

Crimping with not enough pressure can cause loose wire in connector or to much pressure makes wire brittle with even broken strands inside wire itself and break just to mention a couple. I spent most of my time on Heavy Commercial Jet aircraft as A&P/IA and if you have electrical training I would go to you to collaborate on the best method/approach or ask the Avionics dept. Note sure if you can google however a good source for anyone from homebuilt's to commercial AC is Acceptable Methods: aircraft inspection & repair.

PS: I would pass your crimp it looks good to me.

77tony

What method(s) does Alan use? T

Mother

I agree and the truth will set you free. Retired at the moment however my experience is A-D checks and Flight Test on Heavy Commercial and do miss it "Nothing like the smell of Jet A in the morning". Great to here from another A&P it's a small world.

blown 87

They can be to tight, or too loose, mainly from using the wrong kind of crimper and using the wrong connectors for the wire size.

Doing it the way you showed looks like a very good way.

As far as being different if you had a A&P, while I do not have any Navy training, I doubt you would find much different, if any thing at all.
The reason I asked about the A&P has nothing to do if it is done right, I was just wondering how many had the rating.
Some of the worst work I have ever seen done to cars has been done by Delta A&P mechanics, and that is saying something.

I stand by what I said, the ratio of crimped connections that have failed to carry current all the time has got to be at least a thousand to one compared to a well done solder connection, and I still crimp those for mechanical strength before soldering them for the electrical connections. (PS, even the factory has issues with their connections at times, VW has had a rash of them lately)

One of the hardest things to find on a car is a intermitiant electrical problem and that is over half of the problems we run into with crimped connections, they work fine for a year of so, then a little corrosion gets started, or the loosen up and only work part of the time.

The blue things that fold over them self are really the worst of the bunch, they are called Scotch locks, I will not allow them in my shop.

blown 87

I am sure it is in AC 43 13 some place, and I agree about the OP crimps, they look good to me also.

http://www.faa.gov/regulations_polic...cumentid/99861

Ed Scherer

I've been known to crimp and solder some connections. It often has to do with the quality of the terminals. Terminals for large gauge stuff is almost always crimp-only (usually meaty enough material that crimps well), but the terminals for small gauge wires are often pretty cheap and I just worry about pull-out or otherwise dodgy connection. Just a little bit of solder and you don't have to worry about it.