Dip Soldering, help needed.

[peps1]

Hello guys,

I am the point where I need to get through hole boards soldered up much faster then I'm able to do by hand, but due to the fact there is some component variation in the boards it rules out getting this outsourced to my fab house.

So, I was looking at the option of using a solder pot for dip soldering, having come across this video:


I was wondering if anyone uses this method and could give me some advice on the pros and cons, and any traps for new players!

Or if there was another approach I could consider for getting lots of boards done fast, and without braking the bank?   

Thanks for your time!

[bpiphany]

It took me some experimenting to get going with decent results. I had a lot of bridging on the 2mm headers I mostly do. Temperature, solder time, release speed and angle all plays into how much bridging I get. On double row 2mm headers bridging the last two pairs of the header is pretty frequent. Rather than reapplying flux and dipping again I usually touch up with a sucker and iron. I recently found that lifting the board with a fair bit of travel along the surface of the solder helps a lot. You always need to lift at an angle for anything fairly tightly spaced, or you'll just lift a big blob of solder.

You need to buy a lot of solder. Which can be expensive, particularly lead free. A big pot takes a lot of solder. You'll also produce decent amount of dross, subtracting further from your budget. I'm also not sure of how the composition of the solder alloy drifts from dross production. Professionally I think they add metals as needed to keep the alloy in the correct composition. That's obviously a bit hard to do at home..

And, yeah, it gets hot from time to time.. Stay safe, be focused, have a clean workspace, be sure not to spill (definitely not on yourself).

https://youtu.be/WeBqJ80qdjk

[Cupcakus]

It looks to be essentially wave soldering by hand.  If you design your boards with the solder wells at the end of the pin headers like you would for a typical wave solder board, I bet you won't get bridging on the last pair anymore.

I'm curious what would happen if you put some sort of vibrator/agitator on the boards while you dip them and how that would change the results.

[bpiphany]

I wouldn't think 2mm pitch generally is a problem when wave soldering. In my case adding a couple of "dummy pins" (or perhaps even only pads) would certainly help since bridging is as good as always only between the last pins. All my designs predate me dipping though

I imagine that with an actual wave that travels down the board, solder is pulled away in a more lateral way than can be accomplished when lifting from a flat surface.

It takes some technique and trimming of the process, but even after the occasional clean up needed it's still a big time saver.

Oh, and by the way, for me, solder sometime cling on to other parts of the board. With the solder mask underneath it's pretty easy to just scrape off with a fingernail.