Is a solder pad lifting issue located at my side or a user error

I love this video.

skill + good equipment (which runs as hot as the knob/display says) → WIN
no skill + good equipment → often WIN but also Fails

Skill -> bad equipment + knowing how to handle it → mostly WIN
no skill + bad equipment → FAIL

skill → trusting the temperature knob on iron running way too hot → often FAIL
no skill → trusting the temperature knob on iron running way too hot → guaranteed FAIL

good equipment can compensate skill quite often as well as skill can compensate bad equipment

On newer drivers I have put into the solder pads a plated through hole so its way harder to rip them off even when the glue is killed
I also enlarged pads as much as possible on later driver builds balanced with pad spacing to make it easier to handle them with less skill or less good equipment

The S42 design is from 2017 so pardon its not as good as recent ones, I know the pads are pretty small and narrow together so there is some at lest some skill and/or good equipment needed to get them soldered

So there has to be used quite thin wire and with unregulated hot irons the solder time needs to be like <0.5son the pad
In my opinion the best solution is always tinning the wire and pad separately then connecting them <0.5s with an iron you know is very hot, with a station and below 300°C you have not to worry to kill the glue

P.S.

Usually solder wire manufacturers have recommended temperature setting of like 320-380°C for example for Kester.
This is usually to compensate bad soldering gear so that enough heat gets on the solder connection to form a reliable connection, the problem is that on PCB´s the glue is the weak link at such high temperatures.

In my solder experience with a good clean tip that fits in size and shape the solder job to do you can go easily down to 295°C with a quality solder wire, the risk of lifting a pad is almost 0.

You can solder really a very long time with a tip temperature of 285-295°C on a pad without doing any harm to it if no mechanical force is applied to shear the softened glue, when you remove the heat the glue gets back to original strength.

Of course, you need a good iron and tip so that at the low temperature the heat can flow quickly enough to make a good solder connection.
The tip geometry plays also a big role, I use a tip that is flat and round, so it can touch the Pad on the whole thickness of the tip not just a single tiny spot like a needle shape tip can
I use in 98% of the solder jobs this tip for Weller, www.weller-tools.com/professional

you can put it on a pad with a flat small end or twisting it 180° and have a really big surface

If you don’t tin the pad and/or lead before connecting both its easy to make a too long solder duration,
always follow the right procedure:

I can only support to twist the cable before applying tin, so it does stick together when put on the pad.

1. you use a 3. Hand to hold the lead on top of the pad (which I can’t really support from my solder behavior, setting up a 3. hand takes longer than tinning lead and/or pad)

- heating the pad and lead simultaneously

- add solder wire with flux

  • remove tip as quickly as possible

2. you tin both pad and lead

- tin the pad this can be really quick like 0.5s is possible, but always stay below 1 second

- tin the lead, not too short (tin does not fully wet) and not too long (tin creeps too far into the strands)

  • now heat up the pad, put the lead on the pad quickly and release the heat

3. you tin either the lead with a blob or the pad with a blob

- tin the lead or Pad with enough solder to wet both parts and is making a nice meniscus

- apply flux to the other part

  • place the lead near the pad heat it up and connect both

Even having good soldering skills from many years and professional gear, I do still use the 2. technique, it takes a bit longer but the results are great and the risk damaging the pad is the lowest.

The only drivers I have ever had issues with are the asian ones that have the pads that look crinkly. Well build drivers and about 635F with a proper iron and tip works very well.

I killed one of your drivers lexel :laughing:

I did salvage the 7135s ,mosfet and attiny though :slight_smile:

I’ll use them for something in the future

> Sorry, but I am pissed if people want to tell me it’s my fault the pads lift on his S42 driver

not your fault
but, give him a refund and refuse to business with him again
do NOT send a replacement

Or maybe neither at fault and the PCB material was defective through no fault of yours?
Hilarious advice from slider, I doubt the person will be looking to buy more anyway after a negative experience and having it dragged out onto the boards!

The person did specifically say that that pad and the indicator pad on that batch of S42 boards has lifted without him doing anything wrong or unusual
He also admitted that the ground pad is not defective,
which I simply commented that it is not a separate pad its just a blank copper spot of a solid ground plane, lifting that would be quite surprising

I had before modded for 3 Guys and myself an S42 with those boards and sold quite a few to other BLF members,
its possible that one member had also a lifted pad on this particular driver and then simply did solder it to Pin 2 of the MCU without bothering me as he searched for the solution himself

I have on later boards used bigger mostly pads than 1.25mm and if possible added plated through holes,
so that cooked glue won’t lift the pad as its still connected with copper to the PCB

I wouldn’t worry to much bro

He proberly used one of my soldering irons :laughing:

I fcked up your driver and I didn’t complain

User fault !!! Most times lofted odd can have some solution

You’ve got praise from me anyway and I’ll be buying more from you in the future
Even though I killed a driver

Your drivers are brilliant

Keep calm and carry on

Peace

Chris

And its not that I have never mentioned how to solder pads on drivers

I get way too often asked things that are well described in the sales topic,
like what to solder where and so on

That S42 user also complained I do not deliver a manual for each driver

I have done this before but my iron was broken and i didn’t notice until the PCB melted lol.

It can also happen with drivers that are soldered to the pill cause you need to use so much heat to get it lose from the pill.

Also some Chinese solder is suspect i had one that wouldn’t melt once. Weird stuff! Maybe not enough flux.

It depends.
I have received PCB’s where the copper adhesion was fairly low and you where where likely to lift a pad when reworking it.
On good quality single sided and through plated PCB’s the risk is very low and you really have to fumble before lifting a pad.

On the PCB’s I get today I can use a heat gun or a solder iron* for a long time and I have no problems, even with SMD (The pads are always on on side).

*I usually use a 350°C setting on my Weller iron (I do not know how precise it is).

I wanted to thank you for posting your recommendations on solders you’ve used. The price has really gone up and I’m hesitant to waste money trying different styles.

Regarding the lifting pads: after 25 years in manufacturing I’ve found that despite our best effort things can go wrong when the trusted materials you create products with have defects.
Maybe, and it’s a big maybe, after thousands of boards there was finally a spot with little or no adhesive? Either way, you posted a nice video showing folks how to properly tin and connect wires. I’ve known people who don’t tin and just try to do it all at once, I try to explain that each surface has different mass and you’ll always wind up overheating one of them unless they’re identical. Plus it’s just easier. Oh well, it’s all supposition regarding this one board.
Perhaps you could offer a service where the boards come pre-tinned at connection points for an extra couple bucks so less proficient solderers would be less likely to damage them?
OTOH, as long as it’s not the pads for the emitter you can easily scrape some of the insulating layer off the trace that leads to the pad and bridge with solder or solder+wire. (don’t ask how I know!)
The spirit of replacing a driver is based in DIY and some creativity may be required.

I have never lifted a pad and i do not even know what temperature my iron is, its a 230V 25W or so chinese thingy without temperature adjustment, but it works :wink:

If I was in your position hers what I would do:

- requested from customer to return nonworking driver

- when I receive driver from customer I would send him new driver with wires already soldered, a bit longer so he can cut them as needed but does not have to sloder them at the driver side

  • no warranty if he lift pad/s or mess something up.

Yes, it would be at my expense but I can live with losing 10-15€ what I can not stand are whining customers that can make a lot of negative advertising if they are unhappy.
You already know from any other thing in life, when people are happy with something they won’t go to 10 different forums and brag about how happy they are with this and that but if they are bitter and disappointed they will use every possible situation to spread their experience.

For products I do I offer 1 year warranty that applies to drivers, leds and switches when they are built inside the flashlight by me, if you only buy parts every part is tested before shipping but there is no warranty in this situation, you can test the parts upon reception and confirm they are working (which I always encourage) but when you put them together if there is a short, something will smoke and that’s your fault, there was an option to send the flashlight to me for modification and you would get 1 year as mentioned, if I burn something while modifiyng your light thats my fault and vice versa if you smoke something its your fault, you can buy more parts and try again :slight_smile:

Just received two drivers from Lexel with Anduril loaded and 10 clicks to ramp config…
Sensible bliss :wink: :+1:

The only time I’ve managed to lift a pad is through straight up abuse. Either mechanical force or repeatedly blasting the hell out of it with an iron that’s too hot.

In 20 years of soldering I have managed to lift 2 pads. The first was because I was using an unregulated soldering iron and left it on the pad for too long. The second time I was using a reflow station and lifted a pad from getting it too hot, both times it was my fault. Luckily the first time I was able to repair the Xbox when I was soldering a mod-chip by using a jumper wire on the junction. The second time I ruined a $400 iMac motherboard.

Weller Temperature on the light azure colored mid and top stations is pretty precise, even the old analog with the knob
As I wrote before I do use a Weller station and my default temperature is 295°C, key with low temperature is good solder wire,
I dumped some cheap Chinese 0.3mm I tried once for like 1.5€ didn’t work at all below 350ish degrees, where quality solder wire flows perfectly at 300°C
For general soldering jobs get a wire with 3 or more % flux and a brush or cotton tips with acetone or alcohol to clean up

The regulation on Weller WSP handles and Hakko tips is very fast so it keeps the tip and solder spot at a relative constant temperature

I told him he can use the MCU leg 2 to solder the wire, lifting that and then breaking of the leg is very very unlikely
Usually all drivers with lifted pads for switch or Indicator LED are recoverable using alternative solder spots
Return shipping from the USA and back is so expensive it could pay a new driver instead

I have in the past soldered for free switch wires to drivers because people wrote me they will likely screw it up with their gear and skills
So if you are not sure I can add leads, but often its easier to solder wires on driver side than on the switch

This is good advise. for most pcb, it is not so difficult to make pad lift if you solder with poor skill. I think user who buy board should be aware of challenge and skill required to assemble pcb. Pratice with soldering many small items is a good learning method. Good job!

I second this…just did one yesterday :person_facepalming:
But it was a mix of force and heat…more force, eventually… :zipper_mouth_face: