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I'm only concerned about the factory crimps and connectors. If I was building my own harness, I'd use Deutsch hands down. I don't like anything about working with the Molex connectors supplied by Vans but I don't want to create more work for myself replacing them if these factory connectors are bullet proof.
Bulky and cheap looking. I have only a few in the airplane but worked with thousands in industrial applications. It was rare to have an issue and I would guess those issues were on par with connector failures for any kind of connector.
Compared to solid D-Sub/Deutsch:
Cheap tin plated rolled pins/receptacles. Terrible for low voltage/small signal stuff. Not as bad when used for higher voltage/current applications where contact resistance doesn’t really matter. Practically every 14 I’ve worked on had electrical problems as a result of using Molex.
Wow. I have never considered they would be used for low voltage signal sources. Have always assumed they were only applicable for “power” connectors.
Walt nails it here. They work, I have some that are 30 years old in the Glasair and still going string. Contact resistance varies with age, as most have some light corrosion on the pins. They tend also to have inconsistent pressure on the pins since they are just a thin stamped pin which can also lead to variability. I wouldn't choose them for a build, but I wouldn't swap them out either if I didn't have a reason to.
Looks like this is going on my "re-do" list. I used them (molex) in my wing connections.
My experience with Molex connectors is they do not hold up well when used in an "outdoor" environment, like your wing roots. They will be exposed to rain and dirt. That said, there is an easy trick to greatly improve their durability in this environment. Go to your local auto parts store and buy a tube of Dielectric silicone grease. Unplug the connector. Pack all the cavities with this grease. It resists water and will prevent rust and dirt ingress. I also use this stuff any time I replace a light bulb [14 volt systems]. Coat the socket and the base of the bulb to prevent degradation of the ground connection over time. I agree with Walt. There are much better connectors out there.
Sounds like I'm 50% ok... I used molex mostly for high power, but did use them on my roll trim and flap position sensor.
Congrats on your extensive college credentials, my experience is merely from a mechanics POV working out in the field fixing stuff.
So you soldered all the Molex pins onto the wires in the factory harness?
I sprayed the contacts with ACF-50 before putting the wing root connectors together. Then I put heat shrink over them and then wrapped them with silicone tape. 2-1/2 years so far with no issues.
I pinned my Deutsch connectors and snapped them together. Almost 5 years with no issues.
^^ This ^^I think it’s the number of mate/demate cycles that cause the problem with tin Molex in hand built circuits. Plus if you stick a meter probe in it you damaged it.
Mating Connector: What to Know About Connector Mating Cycles
A mating connector is any method of assembling of two or more component parts with mutually complementing shapes that. Any electrical connector, bolted joint, and jigsaw puzzle is an example of assembling based on mating connection. Mating cycles are important when selecting a connector. Learn...www.iconnsystems.com
The good news, as always, that everyone gets to pick their own poison...
Yeah but it's tough for rookie builders to decide which route to go in situations like these. I have enough obstacles to overcome without worrying about chasing down "self inflicted" electrical issues from using potentially problematic connectors.
Agreed. I found the Deutsch connectors "less problematic"...
Is the Deutsch crimper the same as a dsub pin crimper, or does it require yet another specialty crimping tool?
I have a DMC crimper as well, which I love - when I saw the Deutsch pins, that's what made me wonder if that crimper would work. I only have the positioner for standard dsub pins. If it's that simple, I'll find the right die for the Deutsch pins!
www.buydeutsch.com
I know you know this, but others should be aware that the common DMC AFM8 (the small one) will NOT crimp Deutsch connectors. This turret is only applicable for the larger AF8 crimper. If you only have the AFM8, then yes, you are buying another crimper.I have the AF8 with this turret...
TH163 - AF8 Crimper Turret Head - Wire Sizes 12-24 AWG - Color Coded -
The DMC AF8, qualified to MIL-DTL-22520/1, has virtually limitless application within the specified wire range of 12 through 26 AWG. Over a thousand turret heads are available to adapt the tool frame to your specific military or proprietary contact/wire combination. The 8 impression crimp, which...
I mainly used the DTM shells; with the correct pins, they are rated at up to 7.5 amps continuous. This suffices for a majority of the wiring. The housings can accept pins for 16-22, 18-20, and 16-18 AWG wires. Obviously the lower amp rating applies with the smaller AWG wires. The good news is you can mix wire sizes within each housing, allowing for multiple circuits.
No, I don't think there were any factory harnesses available when I built in 2014
OK, good to know, thanks.
The DT connectors are pretty similar in size to the DTM connectors. I'm working on mine now and I'm using DTM for anything with 22AWG wires and DT for anything else. Technically the crimps for the DT (size 16) only support as small as 20AWG.
Thanks for that clarification. In this case, I'm only referring to the large Molex connectors (not the micro-Molex connectors) that Vans supplies with their factory wiring harness. And specifically, at the wing root of the RV-14.
One nice thing about them is that they snap into place that VANS has created for this style connector. Considering this is really a one time routing/setup and you probably will never touch or mess with it, none of those listed above would be a reason for me to change it. Of course I had elected not to use any of the VANS provided harness as they seem more trouble than worth and did not use any other type connector if the location did not warrant disconnecting cables in the future such as in the wing root area.
The main reason for my connectors is to be able to complete all the necessary installation and testing tasks while in the workshop, 70' from my house. The hangar is at best 40 minute drive, it isn't heated or air conditioned, and nearly all the tools are in the workshop.
Well, this is the purpose of my poll. There are some very experienced folks who say the factory Molex connectors do NOT work. Of course, this is a VERY unscientific poll but as of right now, 5 out of 10 people say they've had problems with their Molex connectors. I could accept maybe a <5% failure rate but not 33%.
