So a guy I was talking to said something about using charcoal soaked in water to make his fuel last longer. I'd never heard of this, and I don't think I've ever seen it mentioned on these forums. Has anyone ever heard of this? 

I've never heard of it. And sounds a bit daft to me. Surely if you're adding wet fuel it will lower the overall temperature of the forge and won't ignite until all the moisture is burnt off?

I've read that soaking cuts down on the sparks, but I haven't tried it and don't know if it's true.  Never heard it makes it last longer.

try it.....

Soaking has always increased the sparking in my forge as the steam blows out bits.  To save on charcoal I build the firepot to hold the needed charcoal---a deeper fire without being wider than necessary so only charcoal contributing to heating the metal is in use.  Sounds to me like someone was trying to use coal forge techniques on charcoal rather than using charcoal forge techniques on charcoal.

Well, it is good to sprinkle a little water on the charcoal that lights up outside of the firepot to keep from wasting it. Other than that I only wet my bituminous coal.

I don't have charcoal outside the firepot.  If I have to use charcoal in my coal forge I add firebricks alongside the firepot to make morte of a "trench forge"

I started blacksmithing using powdered coal soaked in water but dont soak my charcoal.

I have friends that do it I see no real benefit except all the dust turns into a mud that can make a heck of a dome for forge welding

It really depends on how much water and how long it's soaked. Personally I just leave it dry, if anything is see the steam splitting the charcoal, increasing the surface area to burn, which would increase heat BUT greatly shorten fuel life.

I have a very small (10" pipe) portable demo forge that I use charcoal in. Once the whole thing gets hot, it is helpful to wet the outer ring of charcoal to keep it from burning up before it gets pushed into the center.

 

Coal, being denser, does not tend to catch fire by contact as easily as charcoal does.

Rinsing AND letting it dry seems to cut down on sparks. Unless, you know, you rebag it, move it, put it in a drum and then roll it across the yard or any other kind of motion that makes dust.

I tried screening it, didn't help at all.

It could very simply have been a reference to wetting the parts of the fire you don't want burning, as in when the fire spreads, which can be a problem with charcoal.