I have made jump rings for 20 years and have never purchased a fancy jump ring tool. I'm not saying its bad thing but sometime you have to watch your pennies. Here is a few tips:
#1. When you make any kind of jump ring using hard wire or half hard wire you cannot use anything soft where the wire might sink into the mandrel and then you can't get it off. This includes crayolas, wood, plastic etc.
#2. To get that smooth even cut that looks so professional you will need a small rotary cutting when that you can put on a rotary tool (dremil) or a flex shaft. That's the expensive way.
#3. Instead get a good flush cutter, the best you can afford: I use the orange handle Xuron cutters and they going on 7 years old and you can find them for about $19. Don't be fooled by others that look identical with the same features and same orange handle because the steel is different and they don't last too long. There cheap but don't last too long. Make sure it has Xuron on it because you are paying for the way it cuts and the steel its made from.
#4. The aluminum needles are a great idea and there cheap. In the old days i would go to the nearest junk yard and find all typef of metal rods of all sizes for about .50 cents and use them as mandrels. Many i still own and use 20 years later.
#5. If you have a tumbler throw em all in a big barrel tumbler and and let them tumble for about 2 hours and they will be very hard and solid, and that's what you want. Harbor freight has a tumbler, a very good one, for under $50 go here: ----- Its the best tumbler i have ever used for the price and it has two barrels.
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90979
Good luck with your jump rings!
Preston
www.wirejewelrybootcamp.com