Soldering Tips?

[TechSquidTV]

Hey guys, I want to step up my soldering game and get involved in some DIY electronics. I ordered a soldering station from Amazon (fairly cheap) and some stuff from China.

 

One thing I bought was a DIY electronics LED clock kit. I didnt realize that it was SMD, but.. oh well. Im trying it. Im maybe 75% done and it is UGLY, no idea if it will even work. So I have some questions.

 

I believe the soldering tip I am using may be too large but besides that....

 

I have a hard time placing the solder where I would like exactly, the solder kind of builds up on the sides of the conical tip. Where I would like to basically "draw" the solder on the board, I am more drag the soldering iron on the face that has some solder build up on it. How can I more accurately apply the solder?

 

Re-flowing solder doesn't always quite work out. I'm starting to learn that less is more, but it's often hard to get enough solder on the gun to get on to the pad I end up overloading the gun a little to make it easier to get the solder on the bad. Re-flowing a tiny amount of solder seems to work best, so maybe I just use too much. but..

 

So these LEDS have six tiny leads, three on each side.

 

If I pre-tin all the pads with a tiny amount of solder I can generally reflow it after placing the part some times (still very heard, not much clearance, have melted a lot of the plastic housings on the LEDS). Now in the PDF guide they gave me I see people flowing solder across the tiny leads and its flowing onto the pads. When I try that, the solder basically cant get down onto the pad, it suspends itself across the leads, hovering over the pads. Honestly, having a bit of an issue getting the solder to stick to the pads sometimes. It's hard to get the solder to flow down and it often clings to the iron when I pull away.

 

Will a smaller tip basically fix these issues?

[Hackentosher]

Usually a wedge tip is the best as it is pretty versatile, but a fine point can also be useful for finer joints. Personally, I don't like the cone shaped ones because I find it harder to heat up my joint evenly than I can with a wedge. A good middleground is said to be the K knife, favored by @iamdarkyoshi, but I personally have never tried one.

[Unimportant]

1 hour ago, Ampix0 said:

Hey guys, I want to step up my soldering game and get involved in some DIY electronics. I ordered a soldering station from Amazon (fairly cheap) and some stuff from China.

 

One thing I bought was a DIY electronics LED clock kit. I didnt realize that it was SMD, but.. oh well. Im trying it. Im maybe 75% done and it is UGLY, no idea if it will even work. So I have some questions.

 

I believe the soldering tip I am using may be too large but besides that....

 

I have a hard time placing the solder where I would like exactly, the solder kind of builds up on the sides of the conical tip. Where I would like to basically "draw" the solder on the board, I am more drag the soldering iron on the face that has some solder build up on it. How can I more accurately apply the solder?

 

Re-flowing solder doesn't always quite work out. I'm starting to learn that less is more, but it's often hard to get enough solder on the gun to get on to the pad I end up overloading the gun a little to make it easier to get the solder on the bad. Re-flowing a tiny amount of solder seems to work best, so maybe I just use too much. but..

 

So these LEDS have six tiny leads, three on each side.

 

If I pre-tin all the pads with a tiny amount of solder I can generally reflow it after placing the part some times (still very heard, not much clearance, have melted a lot of the plastic housings on the LEDS). Now in the PDF guide they gave me I see people flowing solder across the tiny leads and its flowing onto the pads. When I try that, the solder basically cant get down onto the pad, it suspends itself across the leads, hovering over the pads. Honestly, having a bit of an issue getting the solder to stick to the pads sometimes. It's hard to get the solder to flow down and it often clings to the iron when I pull away.

 

Will a smaller tip basically fix these issues?

First of all, make sure you use the correct solder. You want lead solder, none of this lead free crap, and solder with flux in the core. fluxless solder is useless for electronics. (Consider some form of fume extraction when working with lead solder, for your health, this can be as simple as a fan that keeps the fumes out of your face.)

 

You should always be feeding in fresh solder when you're soldering, never re-flow or resolder "dry" (without adding fresh solder). You need the flux to have a clean joint. reflowing existing solder will always look bad because the flux is already burned off by then by the original soldering. Another option is to add flux first, with a flux pen for example.

 

Soldering SMD by hand is best done using solder wick. The key is both the pads and the components have to be tinned first (solder pre-applied), otherwise it'll be hard to make the solder take and it will look bad. The problem is, once the pad/component is tinned, the pre-applied solder forms a "bulge" wich makes placing the part properly hard and look bad. That's where the solder wick comes in:

 

• Apply solder to the pads on the PCB.
• Wick the solder away with the solder wick, so the pads are nice and flat again, but they'll be tinned - you'll get what I mean immediately when you see it.
• Place the SMD part to install on something heat-resistant with some double sided tape so it stays put.
• Carefully Apply solder to the components pads. Not too much, that'll make it harder to wick.
• Wick the solder away with the solder wick. Be careful not to bend leads when doing SMD IC's for example.
• Place the part with tweezers and tack 1 lead in place so it stays put. This will be easy because everything is already tinned. It does not have to look good, just keep the part in place.
• Now properly solder the other leads of the part properly, by applying (a tiny bit) of fresh solder while soldering, again - never solder dry. You'll see its much MUCH easier now everything has been tinned.
• Re-do the lead you tacked in place last to clean it up
• any excess can be wicked away.

[Aelita Sophie]

2 hours ago, Ampix0 said:

Hey guys, I want to step up my soldering game and get involved in some DIY electronics. I ordered a soldering station from Amazon (fairly cheap) and some stuff from China.

 

One thing I bought was a DIY electronics LED clock kit. I didnt realize that it was SMD, but.. oh well. Im trying it. Im maybe 75% done and it is UGLY, no idea if it will even work. So I have some questions.

 

I believe the soldering tip I am using may be too large but besides that....

 

I have a hard time placing the solder where I would like exactly, the solder kind of builds up on the sides of the conical tip. Where I would like to basically "draw" the solder on the board, I am more drag the soldering iron on the face that has some solder build up on it. How can I more accurately apply the solder?

 

Re-flowing solder doesn't always quite work out. I'm starting to learn that less is more, but it's often hard to get enough solder on the gun to get on to the pad I end up overloading the gun a little to make it easier to get the solder on the bad. Re-flowing a tiny amount of solder seems to work best, so maybe I just use too much. but..

 

So these LEDS have six tiny leads, three on each side.

 

If I pre-tin all the pads with a tiny amount of solder I can generally reflow it after placing the part some times (still very heard, not much clearance, have melted a lot of the plastic housings on the LEDS). Now in the PDF guide they gave me I see people flowing solder across the tiny leads and its flowing onto the pads. When I try that, the solder basically cant get down onto the pad, it suspends itself across the leads, hovering over the pads. Honestly, having a bit of an issue getting the solder to stick to the pads sometimes. It's hard to get the solder to flow down and it often clings to the iron when I pull away.

 

Will a smaller tip basically fix these issues?

GreatScott! just happened to uploaded this video 2 days ago:

 

[TechSquidTV]

1 hour ago, Unimportant said:

First of all, make sure you use the correct solder. You want lead solder, none of this lead free crap, and solder with flux in the core. fluxless solder is useless for electronics. (Consider some form of fume extraction when working with lead solder, for your health, this can be as simple as a fan that keeps the fumes out of your face.)

 

You should always be feeding in fresh solder when you're soldering, never re-flow or resolder "dry" (without adding fresh solder). You need the flux to have a clean joint. reflowing existing solder will always look bad because the flux is already burned off by then by the original soldering. Another option is to add flux first, with a flux pen for example.

 

Soldering SMD by hand is best done using solder wick. The key is both the pads and the components have to be tinned first (solder pre-applied), otherwise it'll be hard to make the solder take and it will look bad. The problem is, once the pad/component is tinned, the pre-applied solder forms a "bulge" wich makes placing the part properly hard and look bad. That's where the solder wick comes in:

 

• Apply solder to the pads on the PCB.
• Wick the solder away with the solder wick, so the pads are nice and flat again, but they'll be tinned - you'll get what I mean immediately when you see it.
• Place the SMD part to install on something heat-resistant with some double sided tape so it stays put.
• Carefully Apply solder to the components pads. Not too much, that'll make it harder to wick.
• Wick the solder away with the solder wick. Be careful not to bend leads when doing SMD IC's for example.
• Place the part with tweezers and tack 1 lead in place so it stays put. This will be easy because everything is already tinned. It does not have to look good, just keep the part in place.
• Now properly solder the other leads of the part properly, by applying (a tiny bit) of fresh solder while soldering, again - never solder dry. You'll see its much MUCH easier now everything has been tinned.
• Re-do the lead you tacked in place last to clean it up
• any excess can be wicked away.

This is pretty on point with what I had discovered about pre-tinning the pads. Looks like some great info.

 

How bad is the lead-free solder? I might switch but I really don't want to have lead fumes around if I don't have to, especially because I work in my room. Solder wick I have on order, knew I would need it. Have a flux pen, seems to be the only way to get solder to stick, so that was the way to go for sure.

 

Im going to continue on like you said. Thanks!

[Unimportant]

8 minutes ago, Ampix0 said:

How bad is the lead-free solder?

It's pretty bad and a large source of failure on modern electronics. Manufacturers are required by law to use lead free for a while now and the amount of dead stuff we receive due to dry/cracked solder joints skyrocketed since then. You can instantly tell when you see it, the joint looks dull, not shiny at all. The solder always acts "dry" - It's hard to explain - it feels more like syrup then proper solder.

 

In fact, the first thing we do when we have to replace a component on a broken lead-free PCB is to add lead solder to the joints first, otherwise it's simply unworkable.

[TechSquidTV]

6 minutes ago, Unimportant said:

It's pretty bad and a large source of failure on modern electronics. Manufacturers are required by law to use lead free for a while now and the amount of dead stuff we receive due to dry/cracked solder joints skyrocketed since then. You can instantly tell when you see it, the joint looks dull, not shiny at all. The solder always acts "dry" - It's hard to explain - it feels more like syrup then proper solder.

 

In fact, the first thing we do when we have to replace a component on a broken lead-free PCB is to add lead solder to the joints first, otherwise it's simply unworkable.

I think I know what you mean by it feeling like Syrup, I'm definitely feeling that. It's like the surface tension is very very high.

[Unimportant]

16 minutes ago, Ampix0 said:

I think I know what you mean by it feeling like Syrup, I'm definitely feeling that. It's like the surface tension is very very high.

This demonstrates it : http://www.youtube.com/watch?v=reNA5iwcg-w&t=4m22s

 

[TechSquidTV]

42 minutes ago, Unimportant said:

This demonstrates it : http://www.youtube.com/watch?v=reNA5iwcg-w&t=4m22s

 

Ya, exactly. Wow. I think that's 70% of my problem right there.

[Ahoy Hoy]

Personally i prefer the thinnest point i can get my hand on.
What you want to do is apply a little bit of solider to the tip of the iron. Then you lower the soilder onto the connection, cable, etc.

If your ever going over old soilder, to repair or change something. You may find it doesnt heat up. Add a bit of fresh soilder to the joint and then suddenly the old stuff just turns liquid.