Thanks to all who gave suggestions in the thread I posted in the "safety" section. I believe I have a fan! Any thoughts I should consider are much appreciated.
Today over lunch, DH and I went to one of the two HVAC places in town. I called them previously about what I was looking for and never heard back. I thought maybe in this small town they just didn't have much. Well, driving past, we noticed a big pile of squirrel cage fans sitting around!
They had a fan from a Carrier 58PAV135-20, never used - the whole thing was being canibalized for parts for other furnaces and the fan was left over. The guy said the "20" meant it would do 2000cfm and that it could handle plenty of SP up to 1.
You may recall I am looking in the area of 1500cfm with SP of .4-.7 depending on duct diameter. After some internet searching, I found the parts manual with the following table (details on other models chopped out):
It appears to me that if I go with 9" duct to achieve the higher velocity, and thus have the higher SP of around .7, I can still run this fan at less than the highest speed and have plenty of cfm. And, if I direct my makeup air very near the bench to avoid constant exchange of my heated/cooled room air, Mark points out that I will need a higher velocity (via extra cfms) to make up for this, which it seems will be no problem for this fan.
Conveniently, it runs on 110, which I already have in the studio area, likely even already on its own circuit and not that of kiln or oxycon, and it already has nice little connectors on the wires, and DH says he knows how to hook it up.
Only drawback of the whole thing is that it does not have single intake so we will have to build a plenum for it. FIL is a metalworker though
Anyone see problems with this plan?
BTW, the suggestion of getting "junk" from HVAC shop was great - I paid $80! Similar new stuff in Grainger was about $500 for something less powerful.
Now to start gathering duct work and find the right duct adapters...
Laura