Just joined up a few minutes ago to see if I could get a little input from people with a little more experience.

 

I'm currently in the process of building my first forge (solid fuel, charcoal and anthracite). However I'm struggling to find a suitable blower. I'd prefer not to use a hair dryer, purely for aesthetics.

 

I've looked at a few bathroom fans, around 50-70cfm. They're cheap, and I know a couple people said those are fine for small projects. But then I stumbled onto a VenTech duct fan. The thing plugs in to an outlet, and it's supposed to be 240cfm. 6" diameter. Wasn't sure if anyone had any experience with these, or if I can't find any info on them because they're junk. They go for about 25 dollars on Amazon. Figured if no one has any info on them, I may just see how it works and let everyone know.

6" ducting plus the needed reducers is going to be more then the 2" for a hairdryer.  Do you remember the old hairdryers that had a blower, and a hose that attached to a cap that you put on your head?  One of those would be a good choice.

These inline fans appear to be optimized for high volume and low pressure.  I could not source a fan curve, so can't be sure. There website does indicate that the 6" fan provides 440 CFM at a required energy input of 121 watts.  Using standard fan calculations this gives us approximately 1.8 " WG of external static at that flowrate at standard conditions.

Also not sure what airflow needed for your coal forge configuration, but think it more likely that you will need relatively high pressure and low flow.  Blacksmith Depot sells one at 112 CFM flowrate at 2.55 " WG external static pressure for smaller forges, so I'll assume that is a good general size (substitute electrical current for the flowrate in CFM, and circuit voltage for the static pressure as a good parallel for analysis). 

Depending on your duct configuration you can use up a lot of the external static pressure capacity of the blower in fittings as well as entry and exit conditions.  Without a fan curve it is hard to tell what static the fan will provide at the lower flowrates you may want for your installation.  Worth trying, I guess, but try to minimize your duct length, offsets and sharp transitions.