Solder question?

Lead free solder made to conform Pb Free certification. In SMD manufacturing the thermal, and joint strength advantage of lead free is too small to make it attractive from technical stand point. Some big manufacturers have to use it whether they like it or not to keep going.
Tin whiskering, higher temp, dull finish, harder flux residue, etc…. are just few of the problems with lead free.
My opinion for us it to go leaded (60/40 or 63/37), unless there’s no other options.
Just purchased a small spool of Indium to test the hype. I’ll let you know if the 50W/MK vs 86W/MK makes any noticeable difference at all in the LED output.

- Clemence

The thick greasy stuff is usually easy to remove with a cotton tip swab when the object you soldered is still hot / warm.
When it cools it gets thicker and stickier, and then you have to use chemicals…

to easy remove flux I like to use rubbing alcohol with brush and swab after soldering :sunglasses:

I used my new Weller a few minutes ago, it’s night and day compared to my old one. Now I’m waiting on a few led’s for some mods.

My next will be Xhp70.2 in a Ultrafire F13.

I planned to build that combo about 16 months ago, but decided I wanted a side switch light instead. I put the light and the HA1 driver in a drawer. Oh well. I built my mini L6 instead. I’ve had a Supfire X17 ready to go for 6 months now waiting on Lexel release his boost drivers with NarsilM.

What driver do you plan to use? A boost driver or use 2 x 26350?

22mm boost driver.

I’ve been using the Hakko 888 in Jason’s video for several years. Love it! I never could solder before, but man I’ve gone through a couple of pounds of solder with this iron! :smiley:

Edit: And for the record? I NEVER apply flux. I use Kester .031 leaded solder with flux core and that is good enough. Some 500 plus lights modded that way, simply do not use extra flux, ever.

I had to double check my parts. I bought a smaller 20mm H1-A boost driver over the H2-C 22mm boost driver because it does 3A. The 22mm only does 1A.

Are you using the H2-C or waiting for MTN E to release his 22mm driver?

Your missing out. The extra flux can certainly help.

I’m gonna be trying out a T12 style iron similar to the Hakko 951 with the integrated heater and temp sensor in each tip. In theory, it can respond to temperature drops very quickly and starts applying additional power to compensate very fast. Faster than the older 888 style tip and heater setup. I hope it works well.

I believe the H1-A and H2-C are only good for up to XHP-50.2.

in my humble opinion, I like the T12-type soldering iron. you can purchase them quite cheap on aliexpress, and use real hakko T12 tips with them. For example:
These work faster than many Hakko or Weller I have used, please give them try.

Hmm, I still got plenty of this blue stuff that looks like washer-fluid, and is a fluxing-demon. Fizzes away as you’re cooking the joint, even a light dab lets the solder wick its way into the wire and make a nice solid joint.

Fiik what brand/formulation it is, as the place had it in a gallon jug and they let me fill a glass juice-bottle (½pt or so) with it. Still got over half left, as just a teeny drop does the job.

The easiest flux to clean are those water based. Stream of faucet water is all it takes. No rubbing/brushing needed. Generally water based flux are more aggressive/corrosive than oil resin/based. And you have to clean it since it will cause corrosion if left on.
My favourite is Zinc Chloride based flux, makes tinning oxidized traces and wires so much easier.

- Clemence

This is what should be arriving any day now. A STM32 2.1S with 8 different tips to try out.

The driver doesn’t know the load, in this instance. 70.2 works fine.

WTF? Definitively no way:

  • H1-A's open circuit voltage goes stock above 14.5V (tested by myself), yet its boost IC (TPS61088) datasheet lists 12.6V maximum output voltage. It has been tested to drive 3S emitters succesfully, but it is limited to 10A maximum input current.
  • H2-C is set to drive 4S emitters by default (XHP35s and such) and can operate with much more power handling capacity when fed by 2S cells. Its boost IC datasheet specifies up to 17A input current. Can be configured to drive 2S emitters (XHP50s and XHP70s). See Buck and Boost Drivers, Testing, Modding, and Discussion (Pic Heavy).


I don’t find extra flux too helpful for new joints, but it makes rework so much easier possible, especially for joints that are a few years old.

I do sometimes use added flux when soldering pre-tinned leads to pre-tinned pads on MCPCBs.

I use a refillable brush pen to apply it.

Electronics grade 99% Isopropanol does a good job of removing rosin flux.

I believe the H1-A and H2-C are only good for up to XHP-50.2.

The driver doesn’t know the load, in this instance. 70.2 works fine.

New to me. And all a know or not know is reading the specs on Kaidomain’s or another’s site.

So would I “notice” any difference in performance with the H1-A vs a listed XHP70 driver?


In the US it is somewhat hard to find solder with lead or blended.

In the US it is easy to obtain leaded solder.