When the ring ends up too skinny to make new holes I use inside retaining ring pliers. It's not like it's something you have to disassemble a few times a day so needs to be super convenient.
What we need is a tiny little drill and tap to make threaded holes, and a tiny little brass screw with a solder tab on it — a standard electrical connection to the aluminum pill.
Or, of course, better designed pills with copper/brass rings integrated in them by hydraulic presses.
K.I.S.S. and/or Occam's Razor. Don't make this stuff more complicated than it needs to be, the simple solution is nearly always better than a complex one.
You don't need a storebought direct-fit brass ring to make an aluminum pill solderable, a narrow strip of copper sheet curled around into a 'C' shape and tapped into the hole with a tiny little hammer or even a plastic screwdriver handle works just fine.
This is an acid flux and NOT for use with electronics
Acid flux types (not used in electronics)
They may work better for attaching two metals to the pill first ..but should NOT be used as general flux for electronics because of their corrosive properties .
instead use a rosin based flux
This is a good question and one that I often see people having trouble with. You really need a tip with enough mass (thermal reservoir) and surface area to contact the pill to get the job done. The normal small pencil or chisel tips have a hard time getting it done in a small amount of time. When I am doing them, I use a wide and fat chisel tip with the temperature cranked up to around 750F with a little bit of flux where I want the solder to flow. It shouldn't take more than 5-10 seconds for the solder to stick, otherwise you are going to transfer a lot of heat into the driver.
If you don't have a big enough iron, the best thing to do is to pre-tin the pill before the driver is in place. That way all of the heat needed to make the solder bond the first time doesn't end up cooking the driver. After you have tinned the piece, it is much easier to get that solder to flow onto the driver.
The advice is well given about making sure not to get flux and then solder onto the outside pill threads.
When I was first getting started and didn't have a good temperature controlled station and various tips, I used one of the $15 big 1100 watt soldering guns to make joints on pills, that also worked. Many people have those lying around.
I did mange to grind it out so it now goes on. I didn’t think it would work because it has to be so thin. It did work, but on the second attempt. I filed a little too much with the first one and snapped it |( So now it’s soldering for that one.
Yep, it’s gonna get hot if it’s on for long. The idea for these lights is to use them to spot rappel anchors on the way down from mountains in the dark (I do a lot of rock and ice climbing in alpine environments). I only expect to use it for short bursts. I’ll be comparing it with my Convoy M1 with MT-G2 and stick with the one I like the most.
Could you give a quick description of your pre-tinning method? This is all pretty much new to me.
Like this:
See the two little arcs of solder?
With a bare pill, it doesn't matter how hot you get it (well, within reason... you don't want it a molten lump of slag). Scrape/sand the target area, wipe down with alcohol or acetone, only put flux where you want there to be solder.
Tinning is when you bond the solder to the other surface. That initial bond between the solder and base metal seems to require more heat and flux than it does to bond two pre-tinned, or soldered pieces together. Without the driver in place, you would basically add a bit of flux to the spots where you plan on soldering the driver to the pill, then add solder until it actually bonds to the pill (tins it). This way you can heat up the pill as much as needed to tin it without worrying about frying the driver. After it has cooled down a bit, but maybe not until it is all the way cool, place the driver back in the pill and solder it into place. It should be a bit easier to do than attempting to tin the pill for the first time.
Again, this is just a work around. The best solution is to get the right tool for the job (a tip with enough thermal mass and contact area to do the joint in 5 seconds or less that won't heat up the entire pill and driver). The bigger tip can transfer enough heat fast enough to heat up the localized pill area hot enough to solder faster than the pill can pull the heat away; otherwise, with a small tip, you have to wait until the entire pill is practically at soldering temperature before that local area is hot enough for the solder to bond.
If you don't have a soldering iron/gun that gets hot enough, you could heat up the entire brass pill with a butane torch and then touch the rim with solder to get it tinned.
I coat the inside of the pill in Flux, throw a chunk of solder in there, and butane torch that into into a puddle. Dip a piece of wire in there, and it’ll stick.
Then solder the other end of the wire to the driver. It reduces battery length some but works well, good ground.
I worked for HOURS trying EVERYTHING I heard about: sand, flux, and:
- Hot iron (tried my Aoyue, set to 480C; cheap 70W from Amazon; a new Weller 140W)
- Torch
- Tried using solder paste on edge of pill
and, EVERYTHING failed :(…
On top of all of that, I changed the tip of my Aoyue to the chisel tip, and afterwards, it wouldn’t come off, and I broke the heating element when I tried, so I had to order a new one :(!!
I don’t know what I’m missing, but there’s got to be something?
For those of you who are able to actually do this (get solder to flow, on the edge of the pill), is it really that easy, or is it a pain (difficult to do) even for you all?
Thanks, and sorry for the mini-rant :(…
First off, the pill you are soldering to is brass or copper, right (or an insert)? What kind of solder are you using?
Ohaya, soldering to your aluminum pill may not be possible. Have you considered electroplating?.
The pill is aluminum. It’s one that came out of one of the lights I modded in the past, I think, but basically, it’s a ring with threads inside and outside. I just picked it out of my junk box to try do the soldering. Depth is about 1/4” maybe, i.e., it’s not a huge pill.
Also, I’ve been holding in my vise when I tried all of this. I don’t know if that matters, but I kept thinking that maybe the vise was acting like a gigantic heat sink, but on all of the things I tried, I couldn’t get the solder to even melt unless I touched the solder directly to the heat source (iron, or to the torch flame)… then the solder would just ball up and fall off onto the floor.
EDIT: The solder was 60/40. The flux I used was the RS paste type flux.
The solder paste (flux with solder that I use to reflow emitters) that I tried (separately) is kester I got off of ebay.
No, I haven’t tried (or considered) that (yet)…
If you have a bench top power supply, give it a shot. All you need is some copper and white vinegar. I have a thread about it somewhere in this sub. I was also going crazy trying to solder to aluminum. Now it's relatively easy, and it holds very well.
You can't solder directly to aluminum with our typical solder.
Exactly. That's why I started electroplating copper and nickel onto aluminum pills.
FYI, I also tried that “aluminum” solder from the electroplating thread awhile ago. That was a no-go (didn’t work) for me also.
So, what type of solder do you use (link would be nice)?
Thanks,
Jim
I just use MG Chemicals 63/37 solder which does not work with aluminum. I prefer RMA flux.