I was trying a draw a large circle for another project and needed a compass. I couldn't believe how cheap the ones were are the local box-marts. They all look like something out of a crackerjack box. where's the metal ones I used when I was a kid? Long story short..... I built one...... and I'm VERY happy with it. I'm going to build more. I put it on you tube to help some other poor sucker out. Check it out and let me know what you think.