I had some friends come down from South Dakota many years ago and apparently you can't get Lone Star and Big Red up there. So when they left the Chevy pick up they and their two Harley's came in left with one Harley and plenty of cases of Lone Star and Big Red and one of them riding one of the...
You need a larger unit. My shop is 1000sqft and minimal insulation with a 36k btu dual zone mini-split and I can keep my shop in the 80's in the Texas heat. I would also suggest putting in some fans for air circulation.
By scoring a line instead of getting the blade in to depth you are just knocking cutting abrasive off of a cheap blade. For your depth get the blade in full and get to cutting. As stated earlier water is your blades best friend and the wetter the better as it will keep the blade cool and help...
Awesome write up. My wife helped me all the way when I built my shop and when we remodeled the house. Last weekend she was right by my side doing a 2 yard concrete pour using my Mudmixer and bag mix, in 100 degree heat.
As someone in Texas that had a 2000sqft metal building that was not insulated, you ain't never gonna get it cool enough to stand. Insulation is your best friend in this scenario no matter what you do with intake and exhaust fans. I had two exhaust fans in that old shop and it was still hot in...
I clamp mine to the workbench when its needed. Doesn't move a bit and I can stick it on a shelf when done. I also don't run it wide open, just enough to get it moving the paint around is all you need.