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kenryan

Joined: 20 Oct 2009
Posts: 426

Posted: Fri Jul 22, 2016 12:38 pm Post subject: connectors explained?

Has anyone seen a good explanation of all (or most) of the various connectors, when to use, when not to use, etc. AMP, PIDG, Molex, etc. are terms that are often thrown around, but never, it seems, explained.



Ken

rampil

Joined: 04 May 2007
Posts: 870

Posted: Sat Jul 23, 2016 2:08 am Post subject: Re: connectors explained?

The terms you mentioned are brand names, in use 30 or more years each.

Without being condescending, the best way to start learning about these devices is to google them when a term comes up that you are unfamiliar with, because you are asking for an encyclopedia.



Selecting links to the manufacturer is probably best (AMP is a manufacturer).

PIDG are connectors for single wires. Molex are (IMHO) cheap, relatively unreliable connectors for multiple wires whose popularity may have had to do with their formerly easy availability at Radio Shack.



If, after you give yourself a bit of baseline, this forum would be a great place to ask detailed questions about aviation applications of the hardware.

_________________
Ira N224XS

alec(at)alecmyers.com
Guest

Posted: Sat Jul 23, 2016 4:01 am Post subject: connectors explained?

What's the basis for the claim that Molex connectors are unreliable?



They're designed to minimise the part cost for mass manufactured products but the correct tooling is very precise and very expensive. If you use cheap tools and don't follow the test protocols the connection may well fail prematurely, but that's not a design flaw in the product.



 	  Quote: 	
		   On Jul 23, 2016, at 6:08 AM, rampil <ira.rampil(at)GMAIL.COM> wrote:

 

 

 

 The terms you mentioned are brand names, in use 30 or more years each.

 Without being condescending, the best way to start learning about these devices is to google them when a term comes up that you are unfamiliar with, because you are asking for an encyclopedia.

 

 Selecting links to the manufacturer is probably best (AMP is a manufacturer).

 PIDG are connectors for single wires. Molex are (IMHO) cheap, relatively unreliable connectors for multiple wires whose popularity may have had to do with their formerly easy availability at Radio Shack.

 

 If, after you give yourself a bit of baseline, this forum would be a great place to ask detailed questions about aviation applications of the hardware.

 

 --------

 Ira N224XS

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=458559#458559

ceengland7(at)gmail.com
Guest

Posted: Sat Jul 23, 2016 4:39 am Post subject: connectors explained?

I'd have to agree that relative to other style connectors for the same application, the molex style connectors can be unreliable. Not pointing a finger at the brand (Molex makes more than one style of connector). But the most common style referred to as 'molex' often has pins made of corrosion-prone material, and weak contact pressure between the contacts. In a 30+ year career dealing with electronics, I've seen frequent (and repeated) failures in everything from consumer electronics to industrial equipment costing in the high 6 figures. The failures I'm talking about are not at the wire/pin junction, but at the pin/pin junction; no tooling issues there.

Just because you see something used in aviation doesn't mean it's high quality. Another example is the edge connector used in a lot of older high end panel mount radios, audio panels, etc.

Charlie

On Sat, Jul 23, 2016 at 6:59 AM, Alec Myers <alec(at)alecmyers.com (alec(at)alecmyers.com)> wrote:

 	  Quote: 	
		  --> AeroElectric-List message posted by: Alec Myers <alec(at)alecmyers.com (alec(at)alecmyers.com)>

 What's the basis for the claim that Molex connectors are unreliable?

 They're designed to minimise the part cost for mass manufactured products but the correct tooling is very precise and very expensive. If you use cheap tools and don't follow the test protocols the connection may well fail prematurely, but that's not a design flaw in the product.

 > On Jul 23, 2016, at 6:08 AM, rampil <ira.rampil(at)GMAIL.COM (ira.rampil(at)GMAIL.COM)> wrote:

 >

 > --> AeroElectric-List message posted by: "rampil" <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>

 >

 > The terms you mentioned are brand names, in use 30 or more years each.

 > Without being condescending, the best way to start learning about these devices is to google them when a term comes up that you are unfamiliar with, because you are asking for an encyclopedia.

 >

 > Selecting links to the manufacturer is probably best (AMP is a manufacturer).

 > PIDG are connectors for single wires. Molex are (IMHO) cheap, relatively unreliable connectors for multiple wires whose popularity may have had to do with their formerly easy availability at Radio Shack.

 >

 > If, after you give yourself a bit of baseline, this forum would be a great place to ask detailed questions about aviation applications of the hardware.

 >

 > --------

 > Ira N224XS

 >

 >

 >

 >

 > Read this topic online here:

 >

 > http://forums.matronics.com/viewtopic.php?p=458559#458559

 >

 >

 >

 >

 >

 >

 >

 >

 >

 >

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alec(at)alecmyers.com
Guest

Posted: Sat Jul 23, 2016 5:23 am Post subject: connectors explained?

If you want more corrosion resistance, use (and pay for) the gold plated contacts. I believe Molex manufacture the 062 and 093 series pins in brass plated with two different thicknesses of gold too - your choice. On the other hand if you want pins at 2 cents each then that's your choice too.

Either way the connectors aren't designed for frequent disconnects - 100 cycles only is the design limit. Beyond that the contact pressure will fail.

Every single PC manufactured since the original IBM PC has used some kind of Molex or AMP crimped pin connection with a nylon housing for things like power supply and floppy disc connectors. That's a lot of opportunities for failure and a lot of time to get things right.

On Jul 23, 2016, at 8:37 AM, Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)> wrote:

 	  Quote: 	
		  I'd have to agree that relative to other style connectors for the same application, the molex style connectors can be unreliable. Not pointing a finger at the brand (Molex makes more than one style of connector). But the most common style referred to as 'molex' often has pins made of corrosion-prone material, and weak contact pressure between the contacts. In a 30+ year career dealing with electronics, I've seen frequent (and repeated) failures in everything from consumer electronics to industrial equipment costing in the high 6 figures. The failures I'm talking about are not at the wire/pin junction, but at the pin/pin junction; no tooling issues there.

Just because you see something used in aviation doesn't mean it's high quality. Another example is the edge connector used in a lot of older high end panel mount radios, audio panels, etc.

Charlie

On Sat, Jul 23, 2016 at 6:59 AM, Alec Myers <alec(at)alecmyers.com (alec(at)alecmyers.com)> wrote:

 	  Quote: 	
		  --> AeroElectric-List message posted by: Alec Myers <alec(at)alecmyers.com (alec(at)alecmyers.com)>

 What's the basis for the claim that Molex connectors are unreliable?

 They're designed to minimise the part cost for mass manufactured products but the correct tooling is very precise and very expensive. If you use cheap tools and don't follow the test protocols the connection may well fail prematurely, but that's not a design flaw in the product.

 > On Jul 23, 2016, at 6:08 AM, rampil <ira.rampil(at)GMAIL.COM (ira.rampil(at)GMAIL.COM)> wrote:

 >

 > --> AeroElectric-List message posted by: "rampil" <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>

 >

 > The terms you mentioned are brand names, in use 30 or more years each.

 > Without being condescending, the best way to start learning about these devices is to google them when a term comes up that you are unfamiliar with, because you are asking for an encyclopedia.

 >

 > Selecting links to the manufacturer is probably best (AMP is a manufacturer).

 > PIDG are connectors for single wires. Molex are (IMHO) cheap, relatively unreliable connectors for multiple wires whose popularity may have had to do with their formerly easy availability at Radio Shack.

 >

 > If, after you give yourself a bit of baseline, this forum would be a great place to ask detailed questions about aviation applications of the hardware.

 >

 > --------

 > Ira N224XS

 >

 >

 >

 >

 > Read this topic online here:

 >

 > http://forums.matronics.com/viewtopic.php?p=458559#458559

 >

 >

 >

 >

 >

 >

 >

 >

 >

 >

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deej(at)deej.net
Guest

Posted: Sat Jul 23, 2016 6:57 am Post subject: connectors explained?

On 7/23/2016 7:59 AM, Alec Myers wrote:

 	  Quote: 	
		   What's the basis for the claim that Molex connectors are unreliable?


	




I was wondering the same thing.  I've been using these types of 

connectors for some 30+ years in a wide variety of applications, and it 

is pretty rare to see a failure.



The ones that have seen issues were typically due to a bad crimp 

installation.  Needle nose pliers aren't the proper crimp tool, despite 

application by many backyard mechanics...  



-Dj



-- 

Dj Merrill - N1JOV - EAA Chapter 87

Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/

Glastar Flyer N866RH - http://deej.net/glastar/

rampil

Joined: 04 May 2007
Posts: 870

Posted: Sat Jul 23, 2016 9:26 am Post subject: Re: connectors explained?

The basis for my opinion regarding molex standard power 0.062 and 0.093 connectors is based on nearly 50 years experience in electronic/homebrew fab. That includes five aircraft and big pile of med lab equipment.



The problems I have seen (more than once) is that they corrode and that the pin/socket combos are not always well fixed in their nylon housings -  they pull out. The wire to contact crimps also occasionally let go on a pull test. And that is with reasonably expensive hand crimp tooling. When I use molex, I have for many years felt the need to solder after crimping.



Yes, you can buy gold-plated contacts, but not locally sourced at ACS, Fry's, Rat Shack, etc.  The reason these connectors are used is that they are locally available, consumer grade, inexpensive products. In their favor, they also will handle more current than a submini DB connector. In my aircraft I use metal shell circular connectors through the firewall and CPC connectors from Panel to fuselage. Inside the panel I use mostly submini DBs and few Molex for multiwire applications, where I accept the molex issues for minor subsystems.



Can I see a show of hands of homebuilders who have access to the automated, precision molex crimp fixtures for their homebuilt aircraft?  I would submit that a connector product that requires that amount of care and precision crimping in fabrication is not a good fit for OBAM aircraft.  I would also observe that in homebuilding and restoring aircraft, that the number of cycles in connecting and de-mating connectors is far more than a handful and not comparable at all to a Dell boat anchor where the power cables to the motherboard and drives are inserted once and (hopefully, but I suppose wishfully in a Dell) never touched again.



Sorry for being long winded, but I have tried to explain the basis for my opinions.

_________________
Ira N224XS

kenryan

Joined: 20 Oct 2009
Posts: 426

Posted: Sat Jul 23, 2016 9:42 am Post subject: connectors explained?

I need to put a connector in the tail section to connect the electric trim servo (Ray Allen). The wires are small, 22 or 24. What would be the best choice for a connector in this situation? It would be possible to use a service loop and splices, but is there a good connector for this application?



On Sat, Jul 23, 2016 at 9:26 AM, rampil <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)> wrote:

 	  Quote: 	
		  --> AeroElectric-List message posted by: "rampil" <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>

 

 The basis for my opinion regarding molex standard power 0.062 and 0.093 connectors is based on nearly 50 years experience in electronic/homebrew fab. That includes five aircraft and big pile of med lab equipment.

 

 The problems I have seen (more than once) is that they corrode and that the pin/socket combos are not always well fixed in their nylon housings -  they pull out. The wire to contact crimps also occasionally let go on a pull test. And that is with reasonably expensive hand crimp tooling. When I use molex, I have for many years felt the need to solder after crimping.

 

 Yes, you can buy gold-plated contacts, but not locally sourced at ACS, Fry's, Rat Shack, etc.  The reason these connectors are used is that they are locally available, consumer grade, inexpensive products. In their favor, they also will handle more current than a submini DB connector. In my aircraft I use metal shell circular connectors through the firewall and CPC connectors from Panel to fuselage. Inside the panel I use mostly submini DBs and few Molex for multiwire applications, where I accept the molex issues for minor subsystems.

 

 Can I see a show of hands of homebuilders who have access to the automated, precision molex crimp fixtures for their homebuilt aircraft?  I would submit that a connector product that requires that amount of care and precision crimping in fabrication is not a good fit for OBAM aircraft.  I would also observe that in homebuilding and restoring aircraft, that the number of cycles in connecting and de-mating connectors is far more than a handful and not comparable at all to a Dell boat anchor where the power cables to the motherboard and drives are inserted once and (hopefully, but I suppose wishfully in a Dell) never touched again.

 

 Sorry for being long winded, but I have tried to explain the basis for my opinions.

 

 --------

 Ira N224XS

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=458571#458571

 

 

 

 

 

 

 

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ceengland7(at)gmail.com
Guest

Posted: Sat Jul 23, 2016 9:59 am Post subject: connectors explained?

I'd consider using the machined sub-d       crimp pins, with heat shrink over the joint. Details are in the       -Connection book.

       

       If you have other lines to the same general location (LED tail       light, etc), and a fairly open path for the connector to pass       through, you could just use a 9 pin sub-d connector.

       

       Charlie

       (interesting that Ira & I share the same experiences with both       molex's and Dells)

       

       On 7/23/2016 12:40 PM, Ken Ryan wrote:

     

      	  Quote: 	
		         I need to put a connector in the tail section to         connect the electric trim servo (Ray Allen). The wires are         small, 22 or 24. What would be the best choice for a connector         in this situation? It would be possible to use a service loop         and splices, but is there a good connector for this application?

       

         On Sat, Jul 23, 2016 at 9:26 AM, rampil           <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>           wrote:

            	  Quote: 	
		  -->             AeroElectric-List message posted by: "rampil" <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>

             

             The basis for my opinion regarding molex standard power             0.062 and 0.093 connectors is based on nearly 50 years             experience in electronic/homebrew fab. That includes five             aircraft and big pile of med lab equipment.

             

             The problems I have seen (more than once) is that they             corrode and that the pin/socket combos are not always well             fixed in their nylon housings -  they pull out. The wire to             contact crimps also occasionally let go on a pull test. And             that is with reasonably expensive hand crimp tooling. When I             use molex, I have for many years felt the need to solder             after crimping.

             

             Yes, you can buy gold-plated contacts, but not locally             sourced at ACS, Fry's, Rat Shack, etc.  The reason these             connectors are used is that they are locally available,             consumer grade, inexpensive products. In their favor, they             also will handle more current than a submini DB connector.             In my aircraft I use metal shell circular connectors through             the firewall and CPC connectors from Panel to fuselage.             Inside the panel I use mostly submini DBs and few Molex for             multiwire applications, where I accept the molex issues for             minor subsystems.

             

             Can I see a show of hands of homebuilders who have access to             the automated, precision molex crimp fixtures for their             homebuilt aircraft?  I would submit that a connector product             that requires that amount of care and precision crimping in             fabrication is not a good fit for OBAM aircraft.  I would             also observe that in homebuilding and restoring aircraft,             that the number of cycles in connecting and de-mating             connectors is far more than a handful and not comparable at             all to a Dell boat anchor where the power cables to the             motherboard and drives are inserted once and (hopefully, but             I suppose wishfully in a Dell) never touched again.

             

             Sorry for being long winded, but I have tried to explain the             basis for my opinions.

             

             --------

             Ira N224XS

             

             

             

             

             Read this topic online here:

             

             http://forums.matronics.com/viewtopic.php?p=458571#458571

             

             

             

             

             

             

             

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alec(at)alecmyers.com
Guest

Posted: Sat Jul 23, 2016 10:48 am Post subject: connectors explained?

 	  Quote: 	
		  >The reason these connectors are used is that they are locally available, consumer grade, inexpensive products. 


	


There's the problem. Using a product because it's locally available rather than the right item for the job is of course going to give you the impression the product is no good.



There should be a clue in the fact that although the pins are available for a few cents each the Molex 093 tool is something like $300, and the AMP mate-n-lok equivalent hand tool is about $500. And those are hand tools for field repair and prototyping only, not suitable for manufacture.



If you use decent tooling, have the correct pin for the size of wire, which itself is correctly stripped to precisely the right length per the manufacturer's specification and then correctly positioned in the tool which is fully cycled - they don't fail pull tests. If you insert them into the shells - and remove them - with the correct tooling only, and only a strictly limited number of times, then they don't fall out of the shells. If you stick to the design limit of connect/disconnect cycles, they don't lose grip. But if you can't meet those parameters, then yes, they'll be "unreliable".



 	  Quote: 	
		   On Jul 23, 2016, at 13:26, rampil <ira.rampil(at)gmail.com> wrote:

 

 grade, inexpensive products.

Mauledriver(at)nc.rr.com
Guest

Posted: Sat Jul 23, 2016 10:53 am Post subject: connectors explained?

No expert here but I'd agree,       especially for 22-24 gauge wires.

       

       If you want a plug connector, use a 9 pin sub-d.  For inline       applications, I zip tie the two plugs together.  Cut and retie as       needed.  That's what I did in my RV10's tail.  Otherwise fabricate       a small mount which I've done for other applications.

       

       If you need to splice individual wires, just use the sub-d pins       without the plug.  heat shrink over the joint.  Removable with       some effort but otherwise very secure and compact.

       

       All of these connector types require professional grade crimpers       and/or development of some technique to get reliable connections       in all situations.  For example, I have a less-than-pro crimper       that required some modification to work reliably.  I recall       doubling the stripped ends of 24 gauge wire worked well as well.

       

       Learning about different connector types and learning to use them       has been fun and satisfying for this builder.

       

       On 7/23/2016 2:01 PM, Charlie England wrote:

     

      	  Quote: 	
		                I'd consider using the machined sub-d         crimp pins, with heat shrink over the joint. Details are in the         -Connection book.

         

         If you have other lines to the same general location (LED tail         light, etc), and a fairly open path for the connector to pass         through, you could just use a 9 pin sub-d connector.

         

         Charlie

         (interesting that Ira & I share the same experiences with         both molex's and Dells)

         

         On 7/23/2016 12:40 PM, Ken Ryan wrote:

       

        	  Quote: 	
		           I need to put a connector in the tail section to           connect the electric trim servo (Ray Allen). The wires are           small, 22 or 24. What would be the best choice for a connector           in this situation? It would be possible to use a service loop           and splices, but is there a good connector for this           application?

         

           On Sat, Jul 23, 2016 at 9:26 AM,             rampil <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>             wrote:

              	  Quote: 	
		  -->               AeroElectric-List message posted by: "rampil" <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>

               

               The basis for my opinion regarding molex standard power               0.062 and 0.093 connectors is based on nearly 50 years               experience in electronic/homebrew fab. That includes five               aircraft and big pile of med lab equipment.

               

               The problems I have seen (more than once) is that they               corrode and that the pin/socket combos are not always well               fixed in their nylon housings -  they pull out. The wire               to contact crimps also occasionally let go on a pull test.               And that is with reasonably expensive hand crimp tooling.               When I use molex, I have for many years felt the need to               solder after crimping.

               

               Yes, you can buy gold-plated contacts, but not locally               sourced at ACS, Fry's, Rat Shack, etc.  The reason these               connectors are used is that they are locally available,               consumer grade, inexpensive products. In their favor, they               also will handle more current than a submini DB connector.               In my aircraft I use metal shell circular connectors               through the firewall and CPC connectors from Panel to               fuselage. Inside the panel I use mostly submini DBs and               few Molex for multiwire applications, where I accept the               molex issues for minor subsystems.

               

               Can I see a show of hands of homebuilders who have access               to the automated, precision molex crimp fixtures for their               homebuilt aircraft?  I would submit that a connector               product that requires that amount of care and precision               crimping in fabrication is not a good fit for OBAM               aircraft.  I would also observe that in homebuilding and               restoring aircraft, that the number of cycles in               connecting and de-mating connectors is far more than a               handful and not comparable at all to a Dell boat anchor               where the power cables to the motherboard and drives are               inserted once and (hopefully, but I suppose wishfully in a               Dell) never touched again.

               

               Sorry for being long winded, but I have tried to explain               the basis for my opinions.

               

               --------

               Ira N224XS

               

               

               

               

               Read this topic online here:

               

               http://forums.matronics.com/viewtopic.php?p=458571#458571

               

               

               

               

               

               

               

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kjashton(at)vnet.net
Guest

Posted: Sat Jul 23, 2016 10:57 am Post subject: connectors explained?

Male and female D-sub crimp pins with a bit of shrink wrap seem like the most elegant solution to me.  Less elegant but OK: two Fast-on tabs.  It is almost as good just to twist and solder a small splice.  If you ever need to remove the device, cut the splice and resolder.

-Kent

 

 	  Quote: 	
		   On Jul 23, 2016, at 1:40 PM, Ken Ryan <keninalaska(at)gmail.com> wrote:

 

 I need to put a connector in the tail section to connect the electric trim servo (Ray Allen). The wires are small, 22 or 24. What would be the best choice for a connector in this situation? It would be possible to use a service loop and splices, but is there a good connector for this application?

alec(at)alecmyers.com
Guest

Posted: Sat Jul 23, 2016 11:17 am Post subject: connectors explained?

DINFor information, on research, I see the Molex 093 pins are rated for a maximum of 25 connection cycles only. 



AMP documentation says their circular mil-style connectors are rated for 25 cycles (tin plated) and 500 cycles (gold plated).

 

A brief review of Amphenol and ITT Canon Subminiature D connector shows the option of DIN41652 Class I (500 mating cycles) or Class II (200 mating cycles) depending on contact material.

 

On Jul 23, 2016, at 14:57, Kent or Jackie Ashton <kjashton(at)vnet.net> wrote:






Male and female D-sub crimp pins with a bit of shrink wrap seem like the most elegant solution to me.  Less elegant but OK: two Fast-on tabs.  It is almost as good just to twist and solder a small splice.  If you ever need to remove the device, cut the splice and resolder.

-Kent



 	  Quote: 	
		   On Jul 23, 2016, at 1:40 PM, Ken Ryan <keninalaska(at)gmail.com> wrote:

 

 I need to put a connector in the tail section to connect the electric trim servo (Ray Allen). The wires are small, 22 or 24. What would be the best choice for a connector in this situation? It would be possible to use a service loop and splices, but is there a good connector for this application?

argoldman(at)aol.com
Guest

Posted: Sat Jul 23, 2016 2:28 pm Post subject: connectors explained?

Lesser the two main problems with the molex type connectors seem to be the crimp connection and the corrosion potential of the connectors.

I

I use them somewhat extensively but I try to circumvent these two problems by the following

1.  Use the proper crimping tool

2. Solder the crimp

3 use heat shrink tubing for strain relief

4 use an antioxidant paste in the connectors

I even use this goo in gold plated (usually flash) pinned connectors as well as fast -ins

   !vm

Gold 



Sent from my iPhone

On Jul 23, 2016, at 7:37 AM, Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)> wrote:

 	  Quote: 	
		  I'd have to agree that relative to other style connectors for the same application, the molex style connectors can be unreliable. Not pointing a finger at the brand (Molex makes more than one style of connector). But the most common style referred to as 'molex' often has pins made of corrosion-prone material, and weak contact pressure between the contacts. In a 30+ year career dealing with electronics, I've seen frequent (and repeated) failures in everything from consumer electronics to industrial equipment costing in the high 6 figures. The failures I'm talking about are not at the wire/pin junction, but at the pin/pin junction; no tooling issues there.



Just because you see something used in aviation doesn't mean it's high quality. Another example is the edge connector used in a lot of older high end panel mount radios, audio panels, etc.

Charlie



On Sat, Jul 23, 2016 at 6:59 AM, Alec Myers <alec(at)alecmyers.com (alec(at)alecmyers.com)> wrote:

 	  Quote: 	
		  --> AeroElectric-List message posted by: Alec Myers <alec(at)alecmyers.com (alec(at)alecmyers.com)>

 

 What's the basis for the claim that Molex connectors are unreliable?

 

 They're designed to minimise the part cost for mass manufactured products but the correct tooling is very precise and very expensive. If you use cheap tools and don't follow the test protocols the connection may well fail prematurely, but that's not a design flaw in the product.

 

 > On Jul 23, 2016, at 6:08 AM, rampil <ira.rampil(at)GMAIL.COM (ira.rampil(at)GMAIL.COM)> wrote:

 >

 > --> AeroElectric-List message posted by: "rampil" <ira.rampil(at)gmail.com (ira.rampil(at)gmail.com)>

 >

 > The terms you mentioned are brand names, in use 30 or more years each.

 > Without being condescending, the best way to start learning about these devices is to google them when a term comes up that you are unfamiliar with, because you are asking for an encyclopedia.

 >

 > Selecting links to the manufacturer is probably best (AMP is a manufacturer).

 > PIDG are connectors for single wires. Molex are (IMHO) cheap, relatively unreliable connectors for multiple wires whose popularity may have had to do with their formerly easy availability at Radio Shack.

 >

 > If, after you give yourself a bit of baseline, this forum would be a great place to ask detailed questions about aviation applications of the hardware.

 >

 > --------

 > Ira N224XS

 >

 >

 >

 >

 > Read this topic online here:

 >

 > http://forums.matronics.com/viewtopic.php?p=458559#458559

 >

 >

 >

 >

 >

 >

 >

 >

 >

 >

 

 

 

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rampil

Joined: 04 May 2007
Posts: 870

Posted: Sat Jul 23, 2016 11:30 pm Post subject: Re: connectors explained?

The wonderful thing about OBAM is that you can do what you think is best!

The downside is that, in the specific application space of OBAM aircraft, there is precious little hard data on reliability, engineering tradeoffs, etc.



Having said that, I offer my opinion about "connectoring" a Ray Allen trim motor/sensor.



Like the majority opinion, I have used minisubDs, roll pin crimp over cheaper folded metal contacts, over soldered contacts. I would use them again in this spot with out hesitation. These connectors do come with tiny screw fastener to retain the male/female but you are asking for trouble in the tail when the self retaining feature is not reliable and you can easily drop the screws, washers and nuts into the fuse. A ty-wrap or friction tape is a good alternative.



No way for the molex connectors here. Primarily because an 0.063 contact is just not compatible with the tiny signal wires used by Ray Allen. 



IMHO solder is a bad choice in this particular spot because of lack of access. Just image the PITA nature of stripping multiple 24 ga wires inside an access panel, then soldering them one by one without melting the adjacent insulation.  Much better to put DB-15s on, before installation in the fuselage.

_________________
Ira N224XS

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Jul 24, 2016 7:37 am Post subject: connectors explained?

At 05:27 PM 7/23/2016, you wrote:

  	  Quote: 	
		  Lesser the two main problems with the molex type connectors seem to be the crimp connection and the corrosion potential of the connectors.

 I

 I use them somewhat extensively but I try to circumvent these two problems by the following



 1.  Use the proper crimping tool

 2. Solder the crimp

 3 use heat shrink tubing for strain relief

 4 use an antioxidant paste in the connectors

 I even use this goo in gold plated (usually flash) pinned connectors as well as fast -ins 	


   None of these things are inherently 'wrong' . . . but

   consider that AMP Mate-n-Lok (Molex cousins) went into

   Cessna ship's harnesses since the 60's with none of

   these 'enhanced' processes. 



   Something we have to keep in mind is that when a company

   with the stature of AMP, Molex, Ampehnol, et. als. puts

   out a new technology with the potential for hundreds of

   millions of wire joinings, they'll have done their homework.



   Install and use these parts within the limits of their

   design goals, your risks are exceedingly low.



 

 

   Bob . . .

dlj04(at)josephson.com
Guest

Posted: Sun Jul 24, 2016 9:24 am Post subject: Connectors explained?

One more thing to keep in mind in the discussion of 062/093 connectors 

(Molex common, AMP Mate-N-Lok etc.) DO NOT MIX gold and tin. A major 

manufacturer of audio/broadcast consoles hoped to improve reliability by 

changing the socket contacts to gold, while leaving the pin contacts 

tin. Reliability went from bad to worse. The tin socket contacts are 

made with very high contact pressure, intended to scrape through some of 

the oxides that accumulate on the tin mating surfaces. The gold ones are 

made with much less contact pressure, because the high pressure would 

scrape off the gold. Mixing one contact gold and one tin is a recipe for 

an intermittent contact.



Extending the wires from a trim servo has to be one of the most common 

FAQs these days. My vote is for solder and shrink (having just done that 

this week in my plane.)

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Jul 24, 2016 5:30 pm Post subject: connectors explained?

At 05:27 PM 7/23/2016, you wrote:

  	  Quote: 	
		  Lesser the two main problems with the molex type connectors seem to be the crimp connection and the corrosion potential of the connectors.

 I

 I use them somewhat extensively but I try to circumvent these two problems by the following



 1.  Use the proper crimping tool

 2. Solder the crimp

 3 use heat shrink tubing for strain relief

 4 use an antioxidant paste in the connectors

 I even use this goo in gold plated (usually flash) pinned connectors as well as fast -ins 	


   None of these things are inherently 'wrong' . . . but

   consider that AMP Mate-n-Lok (Molex cousins) went into

   Cessna ship's harnesses since the 60's with none of

   these 'enhanced' processes. 



   Something we have to keep in mind is that when a company

   with the stature of AMP, Molex, Ampehnol, et. als. puts

   out a new technology with the potential for hundreds of

   millions of wire joinings, they'll have done their homework.



   Install and use these parts within the limits of their

   design goals, your risks are exceedingly low.



 

 

   Bob . . .

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