Recommendations for soldering temperature

[Homer]

Hi again!

I was just wondering what temperature you guys set your soldering irons at when you're soldering the legs of the Arduinos to a circuit board? I was setting mine at 300 degrees C as the store where I bought the soldering station suggested that was the temp I should use, but I'm finding that I get better connections when I'm at 350 degrees C.

Keen to hear what everyone's thoughts are. I did do a search but didn't find anything.

Cheers

[skywatch]

This depends on a number of factors.

1. Tip size and shape will change the optimum temp for soldering.
2. Thermal inertia of the soldering iron station controller.
3. Heating element used inside soldering iron.
4. Type and brand of solder used.
5. Type of solder pad you are soldering to.

It goes on and on. But I usually use 350-380 for that. I prefer a quicker heating of the spot to get a good flow and then done. The lower the temperature the longer you need to apply the heat and the more chance there is of overheating and dry joints.

So it is all down to experience and a little trial and error, which is exactly what you are doing!

[Nca78]

@skywatch said in Recommendations for soldering temperature:

The lower the temperature the longer you need to apply the heat and the more chance there is of overheating and dry joints

Exactly. I never set the temperature below 350°C.

[Homer]

Thanks!

I went and bought a new tip today. The one I had was pointy and I was struggling to heat the circuit board while heating the leg of the Arduino. So I went and bought one that has a flat spot which I saw on a YouTube video. Now I can heat both the board and the leg at the same time and do it properly so the solder flows into the hole. My soldering looks better already, and I'm soldering at a little over 350 degrees C now.

[Yveaux]

@homer For some inspiration: https://www.silabs.com/documents/public/application-notes/an114.pdf

[bjacobse]

https://electronics.stackexchange.com/questions/1980/what-s-the-proper-soldering-iron-temperature-for-standard-031-60-40-solder

And then a comment, I think most people at home use 60/40 tin/lead (Sn/Pb) ratio
At my work it's forbidden to use Pb and then we have some leadfree solder, it's more difficult to use and REQUIRES higher temperature (Just read this as info)

[JohnRob]

Hi,

I usually run my iron at 380 to 390°C for soldering thru hole components. I've been soldering for a long time and found this temp to be the best for my technique.
You should have multiple tips for different size parts. For instance, I solder board headers with a conical 0.032" tip.
The most important item is to have the solder tip wet with solder before you touch it to the board, and touch both the pad and lead at the same time. Feed in a little more solder and watch it flow into the joint...remove tip immediately.
My tip is contacting the joint for 2 seconds, maybe 3 at the most.

[dbemowsk]

I am in the US, so on the imperial measure side of things, I usually run 725° to 750° F which converts to about 385° to ~400° C relatively consistent with what @JohnRob is using. Hobbyists typically use 60/40 or 63/37 solder. @bjacobse had it backwards though, the 60/40 is usually SnPb or tin/lead, not lead/tin. That is 60% tin and 40% lead. Lead free solders are usually an alloy of SnAgCu or tin/silver/copper and require a higher temp and are a bit harder to work with, but if you are looking to comply with ROHS rules, SnPb is out of the question.

[Creaky]

Here is a super interesting article about the science of soldering and how soldering affects electronic components.
Fun fact; ICs aren't watertight!

https://hackaday.com/2019/05/03/get-to-know-the-physics-behind-soldering-and-the-packaging-of-ics/

[bjacobse]

@dbemowsk agree 60/40 Sn/Pb - my post have been edited to be correct

[Homer]

Here is another link on basic soldering tips that I found on one of my local electronics sellers. Here is the link

[bjacobse]

@creaky said in Recommendations for soldering temperature:

Here is a super interesting article about the science of soldering and how soldering affects electronic components.
Fun fact; ICs aren't watertight!

Off cause IC are not watertight.
In real production, IC are either stored in Nitrogen boxes, and/or baked according they MSL level, otherwise when those are running through the reflow-oven they will due to moist, as the moist are becoming damp, yes pop like pop-corn that pops, hence pop-corn effect
https://en.wikipedia.org/wiki/Moisture_sensitivity_level

And the reel (that have the components) are ALWAYS vacuum sealed (with an ESD bag), and MSL level is written on the outside, like lot/batch number and partnumber