Trying to cut steel on Homemade Milling Machine

[Toolmaker51]

I rarely post addresses to sites/ forums that cut into ours. I'm on a lot of them and none have depth of constructive help you'll get here.
That said, I refer to one often because it'll run tables on my phone while out on the floor.
This link is their "Calculator Menu" https://littlemachineshop.com/mobile/menu.php
While drill sizes can be adhered to, I'd use the Speed/ Feed menu at maybe 50-60% the calculations with your current machine.