Nice home made rock saw. I used to have a store bought trim saw along with a slab saw and a four wheel polishing arbor. Unfortunately my ex wife took custody of them even though she had no interest or knowledge in using them. But that's another story.
A couple words of caution. While it is very safe for skin that thing will chew through fingernails before you know it. Trust me, I know. Also, while water is perfectly fine to lubricate most cutting jobs do not leave the blade sitting in the water or that $40 blade will be a rusty mess. You can get additives to prevent that but is probably not worth it unless you are using it in a production setting. Oil or kerosene is often used especially if you're cutting harder material like agate but it's a stinky mess to work with. Stick with the water but don't forget to dump the water when you're done.
Have fun with it, it's a fun tool. Get a few diamond bits for your dremel to do final shaping and you can do pretty much any shape you can think of. I just might have to add that to my list of tools to build, I miss mine.