The two methods I have used are to encourage the components to come off, or to force them with brute force to break off.
First method I like the most...
I found an iron wok at a salvation army store. I then purchased kiddy play sand.
I fill the wok with the same, then put the wok on heat. I do this outside because of the poisonous noxious fumes that solder and PC boards give off when heated.
If you place the PC board on the sand, solder side down, it will heat the solder to melting point and it will be drawn away by the sand. Then later you can simply pluck the components off the board without any issues.
The other method requires a press and two pieces of case hardened steel. You simply clamp off the steel blocks so that the space between barely allows for the PC board to fit in the slot, then you load the board so that it's up and down, end to end. You place something between the press and the board so it doesn't just break the PC board, and then lower your press so that the board goes through the gape, shearing the components off. This will fling components all over the place, what I did was use a drop cloth in a funnel shape all around the press that caught the components and let them fall into a bucket.
Heat guns work also, but you should use a respirator or some sort of breathing mask so you don't breathe in any of the fumes, again they are toxic and can cause neurological damage. In other words if your face starts twitching after a few times doing this, you are affecting yourself in a negative way.
Traditional desoldering works, but it's a pain...
You can dissolve the solder with acids, and then pluck out the components, but this generates NOx gases again, and can be harmful
You can cut them off, but that is time consuming
There are many other ways, each with their merits and issues. Hope this helps some.
Scott
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