Switches: spade vs screw terminals
Posted: Sat Mar 04, 2017 7:06 pm
by Bryan Cotton
All,
The switches I got from Spruce are all spade terminals. I have used that style for auto and hobby use. At Sikorsky and Schweizer we always had screw terminals on our aircraft. What are you using? Anybody have trouble free time with spade switches?
Re: Switches: spade vs screw terminals
Posted: Sat Mar 04, 2017 7:59 pm
by saddler
All of my switches are spade type from Bandc.aero and have been flawless for 105 hrs.
Re: Switches: spade vs screw terminals
Posted: Sat Mar 04, 2017 8:28 pm
by SonexN76ET
I specified screw terminals for my Sonex. The Magnitrons have spade terminals. With the screw terminals you still run the risk of a screw vibrating loose. On my boat I have spade terminals and have never had one come loose. I think it depends on individual preference.
Jake
Re: Switches: spade vs screw terminals
Posted: Sun Mar 05, 2017 2:58 am
by wlarson861
All terminals are “Fast on” type spade terminals. Over 370 hours without a hitch.
Re: Switches: spade vs screw terminals
Posted: Sun Mar 05, 2017 3:15 am
by peter anson
Spade terminals everywhere except the central earth block. I bought a bag of good quality soldered spade terminals and matching insulating boots. No problems in 295 hours.
Peter
Re: Switches: spade vs screw terminals
Posted: Sun Mar 05, 2017 10:21 am
by builderflyer
Bryan,
All spade terminals on switches and the fuse block in my Sonex for 12 years and over 500 hours of flying with no issues. Recently, I attempted to remove a couple of connectors from the spade terminals and accidentally pulled the wires from the connectors instead…if properly installed, those connectors aren’t going anywhere on their own.
Art
Re: Switches: spade vs screw terminals
Posted: Sun Mar 05, 2017 11:25 am
by NWade
A quick note: The spade terminals available at some auto-parts stores (or the auto-parts section of your local big box store or home improvement warehouse) do not have as tight of a fit as the ones being sold at places like B&C Specialty, SteinAir, etc. The auto-parts-store/home-improvement terminals also usually have a harder plastic insulation that cracks when you crimp it and will fall off later.
Choose high-quality connectors with transparent/translucent insulation (which is softer and won’t crack or fall off when you crimp it). Here’s an example of the good terminals, over at B&C.
Here’s an example of the bad terminals (DO NOT USE). Note the cheap solid plastic insulation on the terminals.
Take care,
–Noel
Sonex #1339
Re: Switches: spade vs screw terminals
Posted: Sun Mar 05, 2017 11:27 am
by Bryan Cotton
All,
Thanks for the replies. Noel, you read my next question before I could type it!
Re: Switches: spade vs screw terminals
Posted: Sun Mar 05, 2017 4:45 pm
by sonex892.
Hi Bryan
I am happy to use either screw or spade. With either lug the most important thing is the method of crimping. Use only a good quality ratchet crimper. If you are a novice electrician use wire strippers. Resist the temptation to twist the strands prior to crimping. No lug, no matter what the wire size requires, the wire to be twisted. Do not nick or scratch the copper.
I do agree with Noel regarding using good quality lugs. I’m not sold on the fact that translucent are any better than the harder red / blue / yellow lugs. If you use good quality crimpers and lugs you will not crack the plastic.
Steve
Sonex 892
Re: Switches: spade vs screw terminals
Posted: Sun Mar 05, 2017 11:50 pm
by wlarson861
The other thing about the good quality Fast-on’s from aircraft suppliers is they have a small flared piece that is designed to capture the wire insulation. The cheapies don’t have that and loose holding strength.
Re: Switches: spade vs screw terminals
Posted: Mon Mar 06, 2017 11:05 am
by DCASonex
wlarson861 wrote:The other thing about the good quality Fast-on’s from aircraft suppliers is they have a small flared piece that is designed to capture the wire insulation. The cheapies don’t have that and loose holding strength.
Those aircraft grade grade crimp terminals also require special crimp dies with separate portions to crimp wire and the portion around the insulation, not the standard el-cheapo ones in big box stores. (Especially avoid HF’s cheap ones. Stripper, crimper I got from them for auto tool box went straight into recycled metal bin after first attempt to use it, would not fully close. Have found Stein Air Inc. to be another very good source for all aircraft wiring supplies and tools.
David A.
Re: Switches: spade vs screw terminals
Posted: Mon Mar 06, 2017 11:20 am
by builderflyer
I use a quality crimper (the type David A just referred to) and quality connectors like those bought from B & C (not automotive ones) and I test each crimped connection by pulling on the wire to be sure it won’t move from the connector. But, over time, a few of the wires have still surprisingly loosened from the connector. So I’ve gone to soldering the tip of the wire inside of the crimped connector to eliminate that possibility (being careful to not allow any solder to wick any significant distance up the wire especially to where fatigue of the wire could become an issue). Sort of like the “belt and suspenders” principle. Worth the extra time to me.
Art,Sonex taildragger #95,Jab3300 #261
Re: Switches: spade vs screw terminals
Posted: Mon Mar 06, 2017 12:17 pm
by n982sx
Frankly, after using nothing but spade terminals from B and C for my Sonex, I wouldn’t even consider using screw on terminals. The fastons work great and hold well. Get a good crimper, good quality terminals and you’re set. You’ll never go back.
On my 14, I have a couple of places aft of the firewall where the component forces me to use a ring terminal to connect to a cheap screw mount and they are the most concerning to me.
Re: Switches: spade vs screw terminals
Posted: Mon Mar 06, 2017 3:59 pm
by WaiexN143NM
Hi all ,
Another good practice is to use some shrink tubing around the crimped connector and the wire. Helps support the crimped wire, and keeps moisture out.
WaiexN143NM
Michael
Re: Switches: spade vs screw terminals
Posted: Wed May 24, 2017 9:48 pm
by lutorm
I’ve had spade connectors (OEM ones) vibrate loose on various motor vehicles, so I’m not fond of them at all. Maybe if you use high enough quality they’re mostly OK, but I much prefer a connection method that has a positive means of retention. Also, if they’re at all exposed to the elements, once you get some corrosion in there things are going to go downhill.
These days, there are many high-quality weather-sealed connectors one can use. I’ve used Metri-Pack, which are good for current-carrying wires but a bit on the large side, Ampseal (good if you have a lot of connections, like 23 or 40 pins) and Mizu P-25 (2-4 pin, tiny). You need an open-barrel crimp tool but nothing fancy, $30-40 bucks and you get something decent that works well once you learn how to do it.
Re: Switches: spade vs screw terminals
Posted: Thu May 25, 2017 2:28 pm
by 9GT
For all your electrical and Avionics needs I highly recommend Steinair. They carry aviation grade and quality electrical supplies and avionics at GREAT prices. Phone consultations and advice are always welcome also. They generally ship on the same day ordered also. No relation,just a satisfied customer. http://www.steinair.com/
Re: Switches: spade vs screw terminals
Posted: Fri May 26, 2017 2:10 am
by NWade
lutorm wrote:I’ve had spade connectors (OEM ones) vibrate loose on various motor vehicles, so I’m not fond of them at all.
That’s understandable - most of the automotive spade terminals are crap - definitely loose and wide tolerances in size. I would never use automotive spade terminals in an aircraft. They look almost identical to decent-quality aircraft spade terminals, but they’re not created equal. See my previous post on page 1 of this thread, where I illustrate some recommended and non-recommended terminals. The difference under actual connection and use is massive.
–Noel
P.S. My Sonex is not yet flying, but I’ve used spade terminals for all of my Sailplane wiring for 10 years and never had a good-quality connector come loose from its fitting or have a wire drop out of a crimp connection, despite flying in all kinds of turbulence (rough air = lift)