I just can't solder the driver to the pill!

Hey guys.
I'm trying to replace the driver on my Ultrafire C3. I finally got the old one out, and now I'm just trying to get the new driver where it belongs...
But the problem is: I can get solder on the PCB of the driver, but having a firm connection with the pill is a complete different story...
I've tried sanding the surface a bit, flux, etc... The pill is dirtfree...

If the pill is aluminm, then youre not going to be able to without special flux for aluminum.

If its copper, then you might not be getting enough heat into the pill fast enough to solder it.

what is the pill made of? if it is Al then it is difficult (impossible) to get solder to stick to it.

Hmm... Thanks.
I'm done with it for now. One of the lead wires broke off again. LED + Driver are going in the parts bin.
Good thing I got a free replacement from DX.

Dutchprep said:

Hmm... Thanks.
I'm done with it for now. One of the lead wires broke off again. LED + Driver are going in the parts bin.
Good thing I got a free replacement from DX.

Click to expand...

One forum member successfully electroplated to aluminum in order to solder to it.

I think he electroplated nickel, copper, then nickel to get good adhesion.

Electroplating baths are not friendly to electronics, just to heatsinks.

What about brass heatsinks. Is there a technique to solder to that? I've had trouble with this in the past.

allburger said:

What about brass heatsinks. Is there a technique to solder to that? I've had trouble with this in the past.

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Heat! You will not get a good bond with a 25W soldering iron. Try with 80W .

Well, the pill is made out of Aluminum, but it seems like it has some brass rings on top. Tomorrow I'll try again using the 100W iron. (dubbed 'The Blister Blaster')
Won't this damage the driver?

Yes it will, if you aren't careful. Heat the ring only to get some solder to stick (preferably not flow violently, then it is to hot). If you have two soldering irons, why not use both. Heat the ring enough with the big iron, and then solder the driver with the smaller one .

If you really have trouble, you can first solder a wire to the ring and than the wire to the driver.

Brass rings can be soldered with a smaller iron than 100 watt BTW, big heatsinks are more difficult. They do just that : sink the heat away. A 100w can heat a brass heatsink locally when it is not a huge chunk of metal. If it were copper, it might be a different story due to the heat transfer

Another suggestion is to "tin" both the pill and the driver. Use rosin solder flux to add solder to selected spot, then place the driver in the pill add a tiny bit of flux and quickly heat the two spots. Done correctly you'll have a nice clean solid joint. Good luck.

^Gurthang said:

Another suggestion is to "tin" both the pill and the driver. Use rosin solder flux to add solder to selected spot, then place the driver in the pill add a tiny bit of flux and quickly heat the two spots. Done correctly you'll have a nice clean solid joint. Good luck.

Click to expand...

+1
It also seems to help if you scratch or file the pill a little where you are soldering giving you a fresh clean surface for the solder to stick to.

I'll add my experience to this thread. I recently made a drop-in and had trouble soldering to the brass pill. I used flux, a 40W iron (upgrade from my previous 25W), and none of that RoHS solder crap, I got me the leaded stuff. If you have a weak iron like that, I'd wait to mount the LED until the very end, because I ended up damaging my LED from too much heat. It still works, just has a dimmer area on it.

so, +1 to more wattage. More wattage means heat faster, means that area gets hotter before the heat has a chance to spread out, means easier soldering!