Hi, So sorry to hear about your little one. When your family is unwell it makes things like work insignificant. I wish you well.
In my opinion (and it is only my narrow minded thoughts) it a rock and a hard place when starting up. You either work your day job and then in the evenings work your bollocks off trying to get work out, or you take a leap of faith and work just on your own business from day one. If you can amass some work and get a machine ready to go, then hand your notice in and go for it. As I said, its a double edged sword, you can achieve more doing it full time but the risk is greater. If I had my time again, I would look into additive engineering as opposed to our subtractive engineering. There are so many good people trying to earn a crust in the worst end of engineering that I really wonder why, when in another 25 - 30 years, a milling machine will a long forgotten oddity. Unfortunately, the technology is still prohibitively expensive to all but the richest of companies. So back to square one. Damn!
Its not easy but, it is possible and if that's what you want to do and your wife is behind you (very very important), go for it.
RHK