One of the most diffcult parts of becoming a knifemaker, is understanding the necessity for a "good" grinder. Its the center hub of just about everything you do in the shop. When I started out I had the same "I can't afford that" attitude that most folks do. I can tell you from costly experience..... save, beg, borrow, or whatever you have to do to buy one of the "top tier" grinders. I went through several attempts at homemade grinders, then purchased a 2x48, then a cheaper 2x72, and finally, after having spent 3x what a "top tier" grinder would have cost me, finally started saving my pennies. It took me a couple of years to save up the money, but I finally ordered my first "top tier" grinder. That one was a Wilton Square Wheel (this was LONG before anything like the KMG or its clones came along) and its still working in my shop to this day. My favorite grinder is my KMG, and I also built a modified version of the EERF grinders.
I know I've made many similar posts to this one, but let me try to say it another way...... Its not that you can't afford one of the top tier machine..... the fact is you can't afford not to have one of them, and you'll be money ahead if you just save up and purchase one. Another fact is that you can spend $200-$500 on the lower end grinders, and that money is GONE...... you will never recover any of it. However, with one of the "top tier" machines, its going to hold it's value, and even a decade down the road, if you decide you want to sell it, you will get very close to the money you spent out of it.