Van's Air Force

The definitive Van's Aircraft support community! Buying, building or flying an RV? Join our exclusive family of mentors and enthusiasts!

Are there different sizes of D-sub pins?

Phyrcooler

Well Known Member
Trying to reconnect the tiny (26 ga ? - why?!!) wires for my Ray Allen pitch trim servo. (RV-9A - purchased flying) Saw on previous threads and a Steinair video, the recommended use of d-sub connectors covered with shrink tube. Ordered some d-sub connector pins that stated they were D-sub connector size 20 - for 24 to 20 AWG. Received the pins today, and discovered that they are TINY! I can’t imagine a 26 fitting, let alone a 24 - 20. Overall length of the connector is roughly only about 9/16” - trying to measure through the container. Am I missing something? They look so small that I’m hesitating opening the package with the possibility of needing to return them. Maybe it is deceiving, and I can actually squeeze the wires in there - but the overall product is pretty tiny compared to what I was expecting. (Frustrated that my EAA class on Electrical Systems & Avionics class was cancelled a few months ago!) Appreciate any advice!
 

Attachments

  • IMG_8699.jpeg
    IMG_8699.jpeg
    2.6 MB · Views: 89
There are two commonly used d-sub pins (with matching sockets)

High-density: M39029/58-360 (orange-blue-black) for 22-28AWG
Standard: M39029/64-369 (orange-blue-white) for 20-24AWG

The they are both about 9/16" long. I used the regular density ones for the Ray Allen connections, with my crimper set "deep". You can't fit a 20AWG wire in a HD pin, but 22 and smaller works fine.

And, yes, they are small!

High Density:

1736740394061.png

Regular density

1736741012612.png
 
Last edited:
There are two commonly used d-sub pins (with matching sockets)

High-density: M39029/58-360 (orange-blue-black) for 22-28AWG
Standard: M39029/64-369 (orange-blue-white) for 20-24AWG

The they are both about 9/16" long. I used the regular density ones for the Ray Allen connections, with my crimper set "deep". You can't fit a 20AWG wire in a HD pin, but 22 and smaller works fine.

And, yes, they are small!

High Density:

View attachment 78381

Regular density

View attachment 78383
Thank you Bill. I did a bunch of “Googling” - but Google was not very forthcoming with good intel! These that I purchased are supposedly gold plated, and have no color markings. I should have been more patient and ordered from Steinair or ACS - but I was hoping to get back in the air this weekend. I’m stuck until Wednesday now regardless. I’ll give these a go hopefully at that time.
 
Thank you Bill. I did a bunch of “Googling” - but Google was not very forthcoming with good intel! These that I purchased are supposedly gold plated, and have no color markings. I should have been more patient and ordered from Steinair or ACS - but I was hoping to get back in the air this weekend. I’m stuck until Wednesday now regardless. I’ll give these a go hopefully at that time.
There are non MIL-SPEC (commercial) HW that will work just fine, too... these will likely be just fine for your application.
 
Trying to reconnect the tiny (26 ga ? - why?!!) wires for my Ray Allen pitch trim servo. (RV-9A - purchased flying) Saw on previous threads and a Steinair video, the recommended use of d-sub connectors covered with shrink tube. Ordered some d-sub connector pins that stated they were D-sub connector size 20 - for 24 to 20 AWG. Received the pins today, and discovered that they are TINY! I can’t imagine a 26 fitting, let alone a 24 - 20. Overall length of the connector is roughly only about 9/16” - trying to measure through the container. Am I missing something? They look so small that I’m hesitating opening the package with the possibility of needing to return them. Maybe it is deceiving, and I can actually squeeze the wires in there - but the overall product is pretty tiny compared to what I was expecting. (Frustrated that my EAA class on Electrical Systems & Avionics class was cancelled a few months ago!) Appreciate any advice!
I'm guessing they are correct, open the package, strip a wire and trial fit
 
If you just have one or two connectors and don't want to gear up with pins/sockets and crimpers, don't forget you can get D-Subs or HDs with solder cups at Digikey or elsewhere for a few bucks. Put a small piece of heatshrink over each solder joint and use a backshell.
 
Trying to reconnect the tiny (26 ga ? - why?!!) wires for my Ray Allen pitch trim servo. (RV-9A - purchased flying) Saw on previous threads and a Steinair video, the recommended use of d-sub connectors covered with shrink tube.
They are 24 awg but yes small, why not use 22 awg as smallest wire used like almost all avionics producers.
 
If you just have one or two connectors and don't want to gear up with pins/sockets and crimpers, don't forget you can get D-Subs or HDs with solder cups at Digikey or elsewhere for a few bucks. Put a small piece of heatshrink over each solder joint and use a backshell.
Thanks. Unfortunately the builder did not leave a service loop or much slack, coupled with short leads from the servo. It is difficult to feed/position just the wires in ahead of the servo when lifting into place within the elevator. That is why I’m going this minimalist route. Originally I was going to use a Deutsch DTM.
 
One option for very fine wire is to strip the wire back twice as fare and then double back the stripped portion on itself. This makes the wire essentially twice as large. Then crimp the doubled up wire.
 
Trying to reconnect the tiny (26 ga ? - why?!!) wires for my Ray Allen pitch trim servo. (RV-9A - purchased flying) Saw on previous threads and a Steinair video, the recommended use of d-sub connectors covered with shrink tube. Ordered some d-sub connector pins that stated they were D-sub connector size 20 - for 24 to 20 AWG. Received the pins today, and discovered that they are TINY! I can’t imagine a 26 fitting, let alone a 24 - 20. Overall length of the connector is roughly only about 9/16” - trying to measure through the container. Am I missing something? They look so small that I’m hesitating opening the package with the possibility of needing to return them. Maybe it is deceiving, and I can actually squeeze the wires in there - but the overall product is pretty tiny compared to what I was expecting. (Frustrated that my EAA class on Electrical Systems & Avionics class was cancelled a few months ago!) Appreciate any advice!
I just installed the Ray Allen actuator in my RV9. I was going to use the SteinAir method but ended up using a DTM 6 pin Deutsch connector (JReady from Amazon) There is plenty of room in the elevator for the actuator and connector. The Ray Allen actuator wire is 24 AWG. The Deutsch DTM pins state 22-20 AWG but I found the 24 AWG wire worked just fine in the 22-20 AWG pins. Whatever pins you use, its important to have the correct crimp tool. For the Deutsch pins I used new style JReady crimp tool and it worked well. I found a brand new one on Ebay for $100. If you decided to use the SteinAir method you could do so with the Deutsch pins (sans the plastic connector) Good luck.
 
I wish I had used 22 AWG 5-conductor for trim. That Ray-Allen stuff is hard to work with. I did use D-sub everywhere for consistency. The trim wires were tricky but heat shrink helps. I buy parts from Digikey. I keep all the parts in a list so I can find them again. Let me know if you need another part.
These are the sockets I buy.
D-sub Sockets
D-sub Pins
 
Last edited:
Trying to reconnect the tiny (26 ga ? - why?!!) wires for my Ray Allen pitch trim servo.

Welcome to the club of builders who have cursed those tiny, $#!* Ray Allen servo wires and wondered "Why, oh why, did they think using 26 AWG was okay?"

We've been meeting in local watering holes for 20 years, asking the question into our beers. Still no answer.

Good luck!
 
Back
Top