jsharkey

Well Known Member
When you crimp wires into barrel type D-Sub pins are you supposed to catch some of the insulation in the crimp or just the conductor? They always seem very delicate.
Jim Sharkey
 
Jim, We soldered them. I think crimping those really small barrell type D-sub connectors requires a special tool, and I wasn't willing to rely on a "smashed-on" connection.

When soldering, we've developed a good technique: First, tin the wire. Then dip the end of the wire into a good paste flux, and insert 1/2 way into the barrel. Use a small pair of pliers or vise to hold the pin. Now (using a very fine tip on your soldering iron) heat the wire that's still exposed outside the pin body. Apply a very small amount of solder on the wire - it will immediately wick inside the barrel. Once you see that happen, gently slide the wire fully into the hole and remove the heat. Be careful not to use too much solder: doing that allows excess solder to get forced outside the little hole and it will then fill in the edge shown in the drawing below, and that's a problem.

If any solder is forced through the hole in the barrel body, it might get into the edge the locking tabs use to hold the pin in place inside the socket. That can interfere with the locking tabs, and the pin might not lock in place. We recommend making sure the edge shown is free of any solder.
DSub%20pin.jpg

If solder does get into the edge shown, you can use solder wick to remove excess.

Good luck... and let me know if you find out what kind of crimping tool would work on these. I see little tools used on small pins like this routinely costing over $4000 (yes I did type three zeros!! :eek:).
 
tool is 31 bucks

go to Stien Air website and order the little d sub crimper they sell. Excellent little tool

Regards,
Chris
 
oh yeah...

Just catch the wire, not the insulation. Soldering, as mentioned above is a good alternative as well.

Regards,
Chris
 
Crimping tool

When using this tool, you should strip enough insulation away so that none of it feeds into the barrel. The D-Sub socket protects any wire that is exposed. Yes they seem a little delicate but you should never have one come loose or break if you properly intall the wire bundle in the D-Sub connector shell. All the wires should be supported just inside the shell by the screw brace. If the wires are too small, wrap some sort of tape around it so that the shell will hold the bundle in place. You should be able to pull on the wires from the outside without and stress being applied to the wires inserted into the sockets.

http://www.steinair.com/images/store/SAT004.jpg
 
Crimping is better for vibration - soldering can make the wire break off right where its soldered on to the barrel. But if you make sure all the wires are held by the hold clamp
then soldering should be fine.

The right crimping tool makes a HUGE difference!
 
Jim, We soldered them. I think crimping those really small barrell type D-sub connectors requires a special tool, and I wasn't willing to rely on a "smashed-on" connection.

When soldering, we've developed a good technique: First, tin the wire. Then dip the end of the wire into a good paste flux, and insert 1/2 way into the barrel. Use a small pair of pliers or vise to hold the pin. Now (using a very fine tip on your soldering iron) heat the wire that's still exposed outside the pin body. Apply a very small amount of solder on the wire - it will immediately wick inside the barrel. Once you see that happen, gently slide the wire fully into the hole and remove the heat. Be careful not to use too much solder: doing that allows excess solder to get forced outside the little hole and it will then fill in the edge shown in the drawing below, and that's a problem.

If any solder is forced through the hole in the barrel body, it might get into the edge the locking tabs use to hold the pin in place inside the socket. That can interfere with the locking tabs, and the pin might not lock in place. We recommend making sure the edge shown is free of any solder.
DSub%20pin.jpg

If solder does get into the edge shown, you can use solder wick to remove excess.

Good luck... and let me know if you find out what kind of crimping tool would work on these. I see little tools used on small pins like this routinely costing over $4000 (yes I did type three zeros!! :eek:).

I'm glad to see somebody else soldering wires, I just can't trust crimp myself.

I do it this way. I get a piece of 2x4 and drill a hole in it about half the distance of the dsub, than I set the dsub in it. I clean the tip of the solder gun real good, tint it and than take a shop rag and wipe off all the solder, heated. Than I tint the wire, than I put a very small amount of solder in the dsub, than I put the wire up to the dsub and heat the dsub and as soon as the wire goes into the dsub, I remove the heat and hold things real still until things cool. done. The trick is to not let any solder come out the small hole in the dsub, if so, than either cut it off and do it again, or bring out a small file and file off the excess. You should have plenty of left over dsubs, so just putting another one on should be just fine.
 
I do it this way. I get a piece of 2x4 and drill a hole in it about half the distance of the dsub, than I set the dsub in it. I clean the tip of the solder gun real good, tint it and than take a shop rag and wipe off all the solder, heated. Than I tint the wire, than I put a very small amount of solder in the dsub, than I put the wire up to the dsub and heat the dsub and as soon as the wire goes into the dsub, I remove the heat and hold things real still until things cool. done. The trick is to not let any solder come out the small hole in the dsub, if so, than either cut it off and do it again, or bring out a small file and file off the excess. You should have plenty of left over dsubs, so just putting another one on should be just fine.
I have no problem with anyone who wants to solder all their wires but it is WAY more work than just using a good crimper. With adequate support, both ways work just fine. When you use a good crimper, it is very easy to produce a very strong, well connected joint in less time than it takes to get all my soldering stuff out of the drawer and set up! This is particularly true when connecting up the EFIS to the engine monitor to the radios to the autopilot. There must be 200 wires that need pins.
 
Thanks - I do have the "4 indenter" crimp tool. Just wondered if the standard practice was just to crimp the conductor.

I also used some pins from Radio Shack. They have mini Molex type crimps which include a crimp for the conductor and a separate one for the insulation. In spite of this they look a lot flimsier than the barrel type. Fortunately my Molex tool has the small size jaws.

Jim Sharkey
 
I have no problem with anyone who wants to solder all their wires but it is WAY more work than just using a good crimper. With adequate support, both ways work just fine. When you use a good crimper, it is very easy to produce a very strong, well connected joint in less time than it takes to get all my soldering stuff out of the drawer and set up! This is particularly true when connecting up the EFIS to the engine monitor to the radios to the autopilot. There must be 200 wires that need pins.


Not trying to bash either way on connecting wires. But on smaller wire in particular, I've have troubles with wires breaking at the insulation if pulled on too hard. When I tint wires properly, the solder goes up inside the insulation just a bit and stabilizes the wire to the insulation. I like that. Now you can do other things to stabil the wire, but I like my practice. Now if I end up putting an end on my wires by crimping, I still like to tint the wire, than it's nice and stabil at the insulation, and than in some cases, I even put some heat shrink afterwards to make sure it's not going to pull apart.
 
Crimps are the way to go

Boeing, Airbus, etc probably have the right idea. They design them for 5000hrs/year service (that's 13.5hrs/day!) and a total service life of over 100,000hrs. They are 100% crimped. :) Bad crimps are so rare I can't remember the last one. Course at my age I can't remember much anyway. :D:D
 
SubD pin crimping

Yes, crimping SubD pins requires a specific crimping tool, which I bought from SteinAir. Crimping is much easier than trying to solder.... that would be too much like surgery!!

The subD pins have two pair of crimping "tongs". I was taught to crimp the set at the very end of the pin onto the end of the insulation. This gives a strong mechanical bite. In the middle of the pin is a shorter set of "tongs" which is crimped into the bare wire. I crimped all the wires for my dual EFIS & EIS and didn't have to redo any of them.
 
Crimp -vs- Solder

I shoulda known: there is a special tool for crimping these D-sub pins. And thankfully its less than Four Thousand Dollars. I would whole heartedly recommend crimping them rather than soldering, since a nice tool is available at a very reasonable price. (I soldered mine, oh well. But its OK)

IMHO, its always better to crimp than solder. Steve, I know you stated a preference for soldered connections since the solder wicks up inside the wire just a little way and that adds some stiffness to the wire inside the insulation. I agree, that's OK.

But, in terms of industry standards, and known performance parameters, professionals will always prefer a properly crimped connection versus a soldered one.

I've done some pretty extensive research on this by way of developing the Terminal Tool. If I had to do it again (and I will ;)) I would buy the little tool from Stein and crimp them. Faster too!
 
I'm not bashing the crimp. I only had to do a small amount of dsubs. I bought my efis with a harness. the radio didn't have dsubs. I hooked in the ap for dynon and it only took a small amount of dsubs. So for me, I soldered and moved on. Wasn't worth the money for me to buy the tool.