Building a large shop fan

[DIYer]

Thanks Vernon. I didn't take blade speed into account when I asked the question. Good to learn something.

[Toolmaker51]

Finally! I have 3 such fans, one needs a motor but mechanically all are fine. Wanted to build these enclosures a long time. Until now, had puzzled on what to use for screening. Never thought [unaware] of agricultural material, other fencing varieties are flexible. Saved me some RPM testing too, will copy 172.5 recommendation.
Do your large fans 'walk' out of position? 3 wheels [1 crazy, 2 straight] is correct, too many uneven surfaces, 4 usually unstable. Kick-out casters would work too, for parking.

[Frank S]

I have a 48 " er with a 10" pulley but no motor that I have been hoarding for a few years. Without an actual shop I haven't needed it It is just one of those many things I own that I see a potential use for someday so wont get rid of it.
when I finally do get around to pressing it into service I will either mount it high up in an end wall to serve as an exhaust fan of do Like the OP did to make a floor model out of it
I had a floor model once that originally had the 1/2" hardware screen front and back for the safety screen but there seemed to be a significant amount of restriction to the air flow plus the dust build up on the back meant frequent cleaning was required. One day I replaced the rear screen with 1' Poultry wire The motor ran cooler less frequent cleanings( almost never) plus a slight increase in flow This encouraged me to replace the front screen as well. Unimaginable hjow much better the circulation od air was plus a significant reduction in noise it even got rid of the constant hum of the motor

[Frank S]

I took a closer look at my 48" fan today I thought it had a 10" pulley but after measuring it it is a 12" cast iron A section size the Curvature of the blades indicate it was an exhaust fan This would not be a problem as I could just use the motor side as the output but that would mean I wouldn't be able to add moisture saturation media for evaporative cooling without subjecting the motor to a wet environment, should I desire to do so. However I could probably turn the blade around to allow for air flow through evaporation media to keep the motor in the dry.
This would be something for others to think about should they decide to construct a shop fan like the OP has done