Soldering question

[jdduffield]

I’ve noticed that sometimes the solder pools on both sides of the PCB and sometimes it does not. Is it ok if the solder pools on the side you are working with but does not flow all the way through to pool around the pad on the other side? See attachment for example.

 

[Noodles]

A buddy who makes pedals commercially made it very clear to me that solder on both sides is a requirement. That said, I'm pretty inconsistent, but do not have very many issues with failures, noise, intermittent connections etc...knock wood.

I'd love to learn some tricks to becoming more consistent and getting solder on both pads regularly.

 

[Erik S]

My goal is always to get the solder to flow through. Nice looking solder on both sides is a common feature of the gut shots from folks here who I look up to and who's work I consider to be the best. Both sides are connected though, so your pedal should still work fine. I think there is a risk if you're running too cold/ fast that you'll have solder just blobbed on top and not penetrated into the joint at all. Those are more likely to fail. From your pics it looks like you're probably flowing into the joint, just not all the way through. I wouldn't worry too much about those.

As I'm getting into the groove of soldering up a PCB I flip it after the first couple joints, monitor what kind of flow-through I'm getting and adjust my heat time and solder feed amount until things look consistent on both sides. Then when I'm done I'll give the top side a close inspection and I sometimes cheat and fill in from the top a few that I didn't get from the bottom.

 

[Feral Feline]

It's simply down to practice, me thinks.
Not mindless repetition, mind, but really thinking about all the variables

Then you get to know that ...

this PCB supplier uses smaller pads that heat up quicker,​

that .05 solder flows faster than the other, but​

gotta be quick with the .08 solder or it's too much,​

this tip takes longer to reheat between quenchings,​

change the tip out for gnds on back of pots,​

guitar cavities are more awkward to work in than unboxed pedals,​

temp settings for: different tips, types of solder, components...​

etc


AH... Erik beat me to it!

It's not cheating if you reheat and get a good solder-joint — that's the goal and I score accordingly.
Like when the top thins out too much and I have an excess on the other side — reflow it and/or solder-sucker up the excess...

 

[xefned]

The top and bottom pads are electrically connected by a via.

So no, it does not matter. It might make you feel better, but it won't change a thing as far as the electrons are concerned.

 

[JTEX]

Yeah, I wouldn't worry too much. If you get solder on one side and it also fills the inside of the plated hole, it's fine. There's no real need to also wet the pad on the other side - though it's neat when that happens in a nice way.

 

[z2amiller]

I found that I'd get solder to flow through to the other side much more reliably when I started using additional tacky flux - the rosin core isn't always enough. The correct amount of flux is "more"!