The vacuum vise is great. You can put it at any angle you could ever want, and the base is heavy enough to stand up without the suction. There are removeable rubber pads in the jaws. Under the pads is black metal (non-conductive so no shorts when testing drivers) with grooves that hold drivers and other thin parts without having to torque on it too hard. When I’m reflowing, i lightly sit the MCPCB in the groove and heat from the bottom, then when I’m done i tighten the vise down to suck the heat out of it. I’ve used it for soldering, drilling, torching… Just about everything. Highly recommended.
Great thread!
What do you guys use to cover the LED when soldering and reflowing? I don't know if it exist -but a protective film of some sort of heat resistant/ heat dissipating paste would be nice when reflowing.
Edit:
Something like this isolation paste or this Therma-Shield Extreme. Does anyone use something like that?
Edit#2:
Or something maigical like this: :-)
Leds are designed to be reflowed so they don’t need to be protected from those kinds of temperatures.
In fact you may actually cause more damage by shielding part of the led and introducing a sharp temperature gradient and resulting thermal stresses.
When we talk about using a hot air gun to reflow leds, we don’t mean aiming the flow directly at the led dome! That wouldn’t be smart, always heat through the pcb/heatsink.
In the datasheet for all leds there is a “reflow profile” which shows the ideal temperature ramp up (rather slow!) and max allowable temps for a reflow process. As long as you don’t exceed that profile or expose the led to any sharp temperature shocks you shouldn’t introduce any negative effects at all.
There’s also been people doing rather harsh heating and cooling of leds during reflow and even those didn’t seem to suffer much from failure, though that may only be noticeable a year or so down the line.
Want to be sure to get maximum lifetime out of your led, try to follow the reflow profile 
So, it seems many people have had success with many different methods of reflowing but I was wondering if a certain type of solder and solder paste need to be used. I have plenty of 60/40 and a container of solder paste. Any specifics I need to be aware of for reflowing?
I would like to know too :-)
Thanks Linus. I didn't think about thermal stress, and didn't know about the reflow profile. Thanks! :-)
But what about protecting the LED from dirt and greasy fingers, and maybe squirts of boiling flux? And do you clean the LED before the final asembling of the flaslight -if so - which products are good and do not harm the LED dome?
"The n00b is strong with this one" (me :-) )
I’m no expert, but this is what I do:
I bought the cheap “mechanics solder paste” that RMM and other places sell, and I bought a small syringe from a farm store. Then I mixed liquid rosin flux into the solder paste until it was thin enough to go through the syringe.
When I’m reflowing, I loosely place the mcpcb in my little vise, apply the paste to the pads, and squish the led down on top (with my fingers or the handle of my tweezers).
Then I heat the mcpcb from the bottom with hot air until I see the solder flow, give it a few more seconds to make sure it flows all of it, then take the hot air away and clamp the vise tighter to help suck away the heat.
When I’m assembling the build, I polish the dome with the same eyeglasses cleaning cloth that I use on the reflector and lens.
Rubbing alcohol and a soft toothbrush work fine to remove flux residue, just don’t grind on the dome or it might crumble or come off(ask me how I know). The most likely method of damaging the led is by tightening a poorly located reflector. After reflowing test with ~a 3V source before doing a high current test with your driver.
What is your hot air source?
I have been using this. It has a hot air attachment that keeps the flame away from the parts.
I also just bought a little craft/hobby Electric hot air tool, but I don’t know if it will get hot enough.
The bernzomatic torch is nice because it’s very versatile and nimble.
Unless it has a blower attachment, I wouldn’t use it.
The open flame makes it very hard to control. It gets too hot, too fast.
I have and use both of those. The smaller one is indeed handier but the larger one holds more fuel and stands with the hot parts well off the table.
I used the “mechanics solder paste” and a mapp gas plumbing torch to reflow the leds on my triple build.
The Mechanics solder paste actually works pretty good. I have used it to reflow thousands of boards. I don't think it is really 63/37, but the melting point isn't too high, and the price is right. I started using Kester a while ago, but I think that the Mechanics is still a great deal that leaves little to complain about.
I always prefer 63/37 over 60/40. The eutectic melting point is what makes the difference for me, since almost everything I do is handheld.
flux , micro shears,hymostats ,dental pick a butane soldering iron can be handy at times .heat shrink ,diffuser material , solderwick, No-ox-id ,vise grips as a cheap helping hands ,rum,a muse.
Some members use Hemostats here for clamping items. I use a couple of cheap alligator clips. Maybe not as good in some circumstances but better than nothing. I also use a small flat screwdriver for a million things especially whilst soldering. This item l would be lost without.
Just dug through the box I had the torch in and found a blower attachment 
I have a couple of led’s on stars on the way from illumination supply that I will use to practice dedoming and reflow on. Also, some arctic ceramique from them as well. Picked up a vacuum vise from harbor freight and a can of deoxit from guitar center. Will pick up some solder paste soon. I now have just about everything I need to get started. Most of the tools mentioned in this thread I already had. I also got a small sun zy-t13 and opened it up. The driver looks a little different than the one linked in a previous post so I will have to take some pics soon and see if anybody can help me out with modding it. I’ve really been enjoying this thread. Thanks for everyones input!