Safe-T 46110 mmArc Protractor Compass Plus, 15.8 cm Long, Made of Clear Plastic with Bluish Hue, Semicircular Side with Rotating Disc Inset on One Edge, Allows Direct View of Vertex Points

Muy caro para lo que es. Plastico fragil, y la parte que deberia girar no gira libremente, hay mucha friccion y para los circulos mas pequeños es muy dificil hacerlo girar, al final por la dificultad de hacerlo girar, los circulos mal hechos.

Works great. I wanted one of these for drawing circles for wood working. I had a traditional compass that was hard to use on a bumpy surface, and this one works much better. Many of the reviews focus on how the plastic circle sticks to its track and the circles come out very rough looking. This is easily fixed with a little graphite. If you have a tube of graphite, that works best. If you only have a pencil, try to draw along the creases in the compass and get some graphite dust in there. Spin the circle around a bit to spread the graphite around, and the compass will work perfectly.

Very good and useful. Many applications for art and technical drawing. Also used to liven up the bathroom wall with loads of different sized bubbles, good effect.

Has to be repeatedly lubricated to spin properly (which will likely break down the plastic over time). Even then, so much pressure is needed to spin it that light lines with pencil are nearly impossible and sturdy leads break mid circle. The plastic is so thin and flexible it will bow up if your page has the slightest wrinkle.The size of the holes is strange, 1/16th of an inch (1.5mm) at the bottom -- so 2mm leads are too big and 1mm leads are too small. Standard ballpoint pens work great in it, though, no worry about breakage or give with them; too bad you're not typically using ink at the stage of the drawing where compasses are involved.There is some give between the middle circle and outer part. Not enough to make it turn well, mind you, just enough to throw the drawing off by a mm or cause wobbly lines if you're not careful. You'll learn to get around the issue with a few minutes of practice.I don't think I could reasonable replace my compass with this given these issues, but it has its uses. Quickly drawing concentric curves with a 2mm+ gap is a breeze with this. Moving the pen to another hole is much easier than adjusting the compass just the right amount after every pass.This product is not bad but not worth its price.

I used it for about 10 minutes inside the 10-20mm radius and it started to stick and would not rotate without my pencil tip breaking or it catching and messing it up. will be looking for alternatives. however outside the 20mm radius still works fine for larger circles if you hold it down firmly. still not very happy overall