As mentioned, if I take a $800 piece of S7 and spend 6 hours machining it, it's a $1250 die detail, using $60/hr as a shop expense rate, at $75/hr I've made a mere $90.
Your shop is on your property and it costs you 60/hr to keep the lights on and tools sharp? I consider shop rate to have profit in it. It doesn't cost me (1 man shop) 75/hr to pay the bills, maybe 75/day. What's left goes to pay me or grow the business (buy fancy tools). The latter I suppose is the actual profit. At tax time it looks like I made less because I can count a fair amount of depreciation. You also mentioned you're booked of for a month. I would raise prices, until you're not slammed at a rate you don't think is making you money.