Go Down

Topic: noob question: connectors (Read 3006 times) previous topic - next topic

wothke

So far I have been using simple/inexpensive single row pin header connectors (see http://www.aliexpress.com/item/1x40-Pin-2-54mm-Single-Row-Female-20PCS-Male-Pin-Header-connector-20PCS-All-40pcs/1729662116.html) whenever I wanted to "modularize" stuff. I seemed like
a convenient thing since it allows to easily cut off the exact number of pins needed..


Meanwhile I've run into two problems with this approach:

1) unless I sand the connector pins before I solder, the bonding with the soldered wires is poor and the wires easily come off again..

2) the connectors do not seem to be very reliable and I have wasted hours debugging phantom
problems that were ultimately due to some loose contact in one of the connectors..


Any suggestions for more hassle-free connector alternatives?

septillion

1) Sounds like you don't use the proper solder. Does it has flux in it?

2) Don't bake them that long ;) And to solder the female part it can help to plug in a male part to stabilize them (leave them in until cooled).
Use fricking code tags!!!!
I want x => I would like x, I need help => I would like help, Need fast => Go and pay someone to do the job...

NEW Library to make fading leds a piece of cake
https://github.com/septillion-git/FadeLed

CrossRoads

Sounds like you need some Flux to help clean the contacts as you solder.
And perhaps your technique needs work if the rosin-core flux in most modern solder is not doing the proper cleaning.
Are you using lead-free solder? Switch to tin-lead solder, that can be easier to use also. Make sure you have a hot enough iron and a large enough tip for good heat transfer.
This is what I use, I buy the 1 pound rolls. (we assemble a lot of stuff) Clean up with 99.9% anhydrous alchohol, or a lower amount if that's what you can get. (like 90, 95% at the drugstore).
http://www.digikey.com/product-search/en/soldering-desoldering-rework-products/solder/1310838?k=mg+chemicals&pv76=289&FV=fff40014%2Cfff80076%2C2b80002%2C2dc186f&mnonly=0&newproducts=0&ColumnSort=0&page=1&stock=1&quantity=0&ptm=0&fid=0&pageSize=25
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

CrossRoads

You can also crimp on connectors to your wires, or use pre-terminated wires:
female-female, female-male, male-male examples
http://www.dipmicro.com/store/WIRE-JMP40FF
http://www.dipmicro.com/store/WIRE-JMP40FM
http://www.dipmicro.com/store/WIRE-JMP40MM
Can also find single terminated wires, pins, and crimp housings at www.pololu.com to make up any connector you want, such as a 2x3 female end to plug onto an ICSP header on a board.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

DVDdoug

#4
Apr 26, 2016, 10:07 pm Last Edit: Apr 26, 2016, 10:09 pm by DVDdoug
Quote
...since it allows to easily cut off the exact number of pins needed.
I do that all the time with the male headers, but not the females.

Quote
1) unless I sand the connector pins before I solder, the bonding with the soldered wires is poor and the wires easily come off again..
I've done that too and I always add heatshrink which helps a bit.    And you can get header pins with long pins on both sides for more soldering area.    But, those connectors are not designed for direct wire soldering, they are designed to be soldered to a PC board.

Quote
[2) the connectors do not seem to be very reliable and I have wasted hours debugging phantom
problems that were ultimately due to some loose contact in one of the connectors.
The only trouble like that I've had is that the male pins sometimes slide part-way out of the housing and then I get poor contact.       (If they are soldered to a board, of course that doesn't happen.)   

I doesn't make a very good Arduino connector, and I've decided to use aprototyping shield board next time I build an Arduino project...  Then, I can solder wires to the board or solder a different connector to the board.

Quote
Any suggestions for more hassle-free connector alternatives?
There are all kinds of connectors - Do you have a catalog from an electronic parts supplier?   It's usually easier to browse a catalog than a website.    I have the Jameco catalog, and unfortunately Digi-Key no no longer prints a catalog.   Mouser still prints a catalog.

raschemmel

#5
Apr 26, 2016, 11:13 pm Last Edit: Apr 27, 2016, 12:53 am by raschemmel
Quote
the connectors do not seem to be very reliable and I have wasted hours debugging phantom
problems that were ultimately due to some loose contact in one of the connectors..  
There's nothing wrong with the connectors. The problem is your lack of experience with soldering makes it impossible for you to see the cold solder joints you are making. We have all been using the exact same headers you are for many many years and have not had any cold solder joints. The fact that you have not even mentioned flux in your post makes it obvious that you simply do not know how to solder , period and need to learn. If you use the correct solder (60/40 rosen core solder) and some form of flux, either a liquid squeeze bottle or a flux pen and know how to solder , you will not have any problem and will not need to sand the pins. I have been soldering those headers for 35 years and NEVER had even so much as ONE with a bad connection so don't tell me it's the connectors. That's just not true. Learn to solder. Post a photo of your soldering iron, your solder  and a closeup photo of your soldering iron TIP. and a closeup  photo of a connector that you soldered.

larryd

#6
Apr 27, 2016, 12:01 am Last Edit: Apr 27, 2016, 12:02 am by LarryD
Quote
2) the connectors do not seem to be very reliable and I have wasted hours debugging phantom
problems that were ultimately due to some loose contact in one of the connectors..
That will put hair on your chest!
Not too good if you are a female.

Have you read the PDF offered here?

http://forum.arduino.cc/index.php?topic=376971.msg2599211#msg2599211

.
No technical PMs.
If you are asked a question, please respond with an answer.
If you are asked for more information, please supply it.
If you need clarification, ask for help.

Chris1448

60/40 rosin core solder.

Its actually worth your while to spend extra coin here.Not all solder is created equal.
1.5mm solder MHO,, works best for this

Good solder and a 60w solder iron ,with a fine tip properly tinned and you should be able to dot these of with no issues.

septillion

60W says nothing... Just use a decent iron. I have a 15W Ersa which works a treat. But you can also buy a 60W cheapy which solders like crap. And I must say, the cheap/knock off soldering stations from China are pretty decent.
Use fricking code tags!!!!
I want x => I would like x, I need help => I would like help, Need fast => Go and pay someone to do the job...

NEW Library to make fading leds a piece of cake
https://github.com/septillion-git/FadeLed

MarkT

Key tips for soldering:

Correct iron temperature - use a temperature controlled iron, then it will work and you won't
oxidize and ruin the tips so quickly.  The actual setting is higher than the nominal value for the
solder due to temperature drop along the tip, so experimentation required.  If things are charring,
its way too hot.

Use rosin-cored solder - never ever use plumbers solder (these have acid fluxes that corrode
and destroy)

If you use lead-free (a good idea) then use the tin/silver/copper alloy, _not_ tin/copper, because
the former is a true eutectic solder and works.  tin/copper alloy is not eutectic and is horrid (but
cheaper).

All parts to solder must be free of grease - do not finger everything first, bare clean metal...

Always always always clean the tip and apply fresh solder _immediately_ before use.  Otherwise
you are just smearing oxides on everything.  Dripping wet sponge for cleaning the tip works well.

Tin each item first (to tin is to wet with solder)

Then apply iron and solder to the parts to join, solder should melt and flow readily over both parts
and then remove solder, wait 1/2 second and remove iron.  Allow to cool without movement (which
can cause a pasty dry-joint)

If you see any hint the joint is not wetted properly, or you see bubbles forming, you have a bad
joint.   Look at the joint through a lens - compare with pictures of good joints.  Any doubt, start again.

Practice on junk components and boards till you get the knack - it may take a little while, but you
don't want to junk valuable wanted boards and components while learning.
[ I will NOT respond to personal messages, I WILL delete them, use the forum please ]

septillion

- do not finger everything first
Luckily I finished my coffee before I read that line :D

And I still prefer lead solder wayyyyyyy better.

And btw, if you need to set the soldering station higher "due to temperature drop along the tip" you're calibration is just off. Okay, most don't calibrate it but the set temperature should be the temperature of the tip. And a small not for the Chinese stations, most of them are like 50C hotter then you set them (without calibration)...
Use fricking code tags!!!!
I want x => I would like x, I need help => I would like help, Need fast => Go and pay someone to do the job...

NEW Library to make fading leds a piece of cake
https://github.com/septillion-git/FadeLed

wothke

#11
Apr 27, 2016, 12:40 pm Last Edit: Apr 27, 2016, 12:46 pm by wothke
There's nothing wrong with the connectors. The problem is your lack of experience with soldering makes it impossible for you to see the cold solder joints you are making. We have all been using the exact same headers you are for many many years and have not had any cold solder joints. The fact that you have not even mentioned flux in your post makes it obvious that you simply do not know how to solder , period and need to learn. If you use the correct solder (60/40 rosen core solder) and some form of flux, either a liquid squeeze bottle or a flux pen and know how to solder , you will not have any problem and will not need to sand the pins. I have been soldering those headers for 35 years and NEVER had even so much as ONE with a bad connection so don't tell me it's the connectors. That's just not true. Learn to solder. Post a photo of your soldering iron, your solder  and a closeup photo of your soldering iron TIP. and a closeup  photo of a connector that you soldered.
I am indeed not using separate flux (eventhough - judging by the smoke/smell - there seems to be some kind of resin built into my 60/40 solder).. a friend had advised me against the use of flux - so as to avoid having its residues corrode the pcb..

here the photos that you asked for (I only use the thin tip when dealing with 1.27mm stuff..):




septillion

I don't use extra flux, I just use (lead) solder with flux in it. Works great all the time.

I see an Ersa, tips look fine, can't read the solder but I miss a sponge or copper shavings.
Use fricking code tags!!!!
I want x => I would like x, I need help => I would like help, Need fast => Go and pay someone to do the job...

NEW Library to make fading leds a piece of cake
https://github.com/septillion-git/FadeLed

wothke

I see an Ersa, tips look fine, can't read the solder but I miss a sponge or copper shavings.
I am using copper shavings - which I did not put into the photo..

raschemmel

#14
Apr 27, 2016, 02:57 pm Last Edit: Apr 27, 2016, 03:37 pm by raschemmel
Your soldering iron, tips, and solder are garbage and your  friend doesn't know what he is talking about.

You can try buyiing the correct solder, paste and flux and keep you're current iron but I would replace it with a Weller 35B.

Flux doesn't "corode" PCBs, it cleans them so the solder will stick. Throw away all your soldering equipment and buy a Weller WP35 iron.
( it's just an iron , not a temp controlled station)
Order different size tips for it. Buy Kester 44   60/40 Rosen Core Solder in the diameter you need and buy some solder paste and a flux pen or a bottle of liquid flux. The flux needs to be cleaned off with Spray on flux remover  and a flux brush after soldering.
Unremoved flux can remain on the PCB forever with effecting anything.

Go Up