Solder paste and molex crimp conn

[boji]

Not sure if people do this, but I tried it out and it gave me great results, so thought I'd share.

Full soak into crimp and wire while avoiding the connector's outside, and left the raised tab dry too. Minimal flux residue.

 

[ruffrecords]

Not sure what you are trying to achieve here.

Cheers

Ian

 

[Khron]

I could be wrong here, but i'm not 100% sure those are supposed to get soldered anyway...

 

[TwentyTrees]

Must admit I’ve read the same - that soldering creates a potential weak spot without necessarily improving the electrical or mechanical connection of a properly done crimp - not sure I’ve seen this answered definitively one way or the other though.

I could be wrong here, but i'm not 100% sure those are supposed to get soldered anyway...

 

[ruffrecords]

I could be wrong here, but i'm not 100% sure those are supposed to get soldered anyway...

I think so too. A proper crimp is a more durable and low resistance joint than a soldered one. The problem is making proper crimp joints at home. The proper 'industrial' ones strip the wire and crimp it all in one motion but they are way too expensive for DIY. Even the official ratchet hand crimp tools are vastly overpriced.

However, low cost ratchet crimp tools are available.

https://www.rapidonline.com/rvfm-ht-225d-ratchet-action-crimp-tool-ht225d-85-0262

These create a perfect crimp provided you strip the wire to the correct length and  feed it in the right distance into the tool. I struggled for ages with very variable crimp quality until I hit on a very simple solution - use your fingers. This takes some trial and error but it can be done with surprising consistency. When stripping the wire hold it in one hand between the thumb and forefinger to a point slightly longer then the desired stripped length (this allows for the thickness of your stripping tool. The feed the wire into the jaws of the strip until your thumb/forefinger buts against the underside of the tool. Then strip. With practice you can get the correct length almost every time.

Then load the crimp tool with a crimp and give it a couple of clicks so the crimp stays put. Again using  thumb and forefinger grip the stripped wire at the correct point and insert the wire into the tool until the thumb/forefinger again buts up against the underside of the tool .Then crimp.

I use this method all the time now. No longer do I get insulation under the wire crimping area of wire under the insulation crimping area. As I said, with practice I get very consistent results.

I don't know if this method is obvious and/or commonly used but it works for me.

Cheers

Ian

 

[pucho812]

I have done similar things with edac/elco pins. This is because the studios want mogami wire and it is the wrong awg for the edac. The crimp alone can easily come off so we solder it after we crimp a tinned wire. Never gave it much though and never had an issue, but this might be a different scenario.

 

[Khron]

I've got one of those cheapo ratchet-crimpers, but the troubling part is finding the right kind of jaws for the thing. The ones meant for ferrules are a no-go...

 

[boji]

crimp a tinned wire

in light of all the nay-saying, I'll just add that I did read it is bad to tin in advance of crimping. Yes it makes for a solid crimp, but if you melt afterwards the crimp no longer clamps down on the wire as tight.
However, negative reviews about soldering after crimp is new to me.
Without solder, It is as Pucho said, I had a few slip out on me with this 28ga mogami.  I figured a bead on the crimp sealed out any chance at dissimilar metal corrosion, ensured a solid connection, and stiffened the wire a bit which made getting them into the molex housing a breeze.  But with the general thumbs down from nearly everyone I'll guess I'll just trust the crimp and get some glue-lined heat shrink for final dressing so all wires share longitudinal tension.

 

[radardoug]

I solder small connectors like this, the HE14 series and Molex. Makes for a more permanent reliable joint. No failures in 20 years!
Works for me.

 

[ruffrecords]

Without solder, It is as Pucho said, I had a few slip out on me with this 28ga mogami. 

Looks like the problem is not the crimp process but using the wrong gauge wire. I used Van Damme 'console' cable which is 24 gauge and works perfectly with Molex KK crimps:

http://www.van-damme.com/wp-content/uploads/2018/10/Van_Damme_Reduced_OD_Console_Cable.pdf

Cheers

Ian

 

[Rochey]

I've had many a lab technician talk to me about this topic, many repeating what Ian said about a *good* crimp being better than solder.

I've purchased my fair share of Molex/JST-XH Crimp tools. Bought fancy ratcheting ones from ebay etc.... In the end, I bit the bullet and bought a manual one made by a Japanese company called "engineer".

http://www.engineer.jp/en/products/pa09e.html
https://www.amazon.com/Engineer-PA-09-Micro-Connector-Crimpers/dp/B002AVVO7K/

Yes. $40. More than you'd think for a hobby tool.

Probably one of the best $40 I've spent for my lab.

Do yourself a favour. Spend it *this* time, and take this topic off the table. Get back to doing the fun and harder audio stuff.

 

[ruffrecords]

Do yourself a favour. Spend it *this* time, and take this topic off the table. Get back to doing the fun and harder audio stuff.

+1

 

[Gold]

With Mogami and EDAC’s I strip twice the length needed to crimp the pin. I fold the stripped wire back on its self to double the thickness. Then crimp. It has always worked well for me. That’s how I was taught to do it. I can’t remember who showed  me that. It’s a good trick. I’ve used it for other things too.

 

[Monte McGuire]

However, negative reviews about soldering after crimp is new to me.
Without solder, It is as Pucho said, I had a few slip out on me with this 28ga mogami.  I figured a bead on the crimp sealed out any chance at dissimilar metal corrosion, ensured a solid connection, and stiffened the wire a bit which made getting them into the molex housing a breeze.  But with the general thumbs down from nearly everyone I'll guess I'll just trust the crimp and get some glue-lined heat shrink for final dressing so all wires share longitudinal tension.

The main danger is that the solder wicks into the stranded wire, makes it 'solid' and therefore concentrates any further flexing force onto a small portion of the cable, right where the still stranded part of the cable meets the new solder fillet. If you can get the solder fillet to be well inside of the strain relief feature of the crimp, then I guess it could still be somewhat safe. But otherwise, you'd need to add some heatshrink or some other system to prevent flexure right at the interface between the solder fillet and the still stranded wire.

 

[boji]

Really appreciate everyone's replies and comments, thanks so much!

 

[boji]

Probably one of the best $40 I've spent for my lab.

Do yourself a favour. Spend it *this* time, and take this topic off the table.

Rochey has the Texas Instruments badge plus 1,347 more posts on this forum than me, so ok.  I shall order it.  8)

Ian thanks for the Van Halen cable recommendation.  The 28ga issue is because I'm still stuck on the Damn single-core fader wire caravan.

 

[Rochey]

Ha. Thanks for that Boji.

Other small recommendation. Use hookup wire made with silicone. Wonderfully flexible stuff and doesn't melt with the soldering iron.

https://www.adafruit.com/product/2051

Also -  I am in love with tools by Hakko. (https://www.amazon.com/s?k=Hakko+chp&ref=nb_sb_noss_2)
Most of them are about $10, and again, instead of needing lots of different pliers etc, I just use one.

And... Finally. The mother of all assembly tools:
https://www.amazon.com/Hakko-TP-5000-15-D-Hardened-Construction-Dissipative/dp/B00FZPRHJ2/ref=sr_1_26?keywords=Hakko+chp&qid=1563874567&s=gateway&sr=8-26
Cuts and bends legs of components so they stay on the board while you flip it over to solder.