I was just going to amplify on what Kevlar started. Measuring throws with a ruler is quite precise. I know most of the manuals for beginner planes list throws this way, but you should get in the habit of using degrees of throw, not inches of throw.

While not impossible, it is hard to accurately measure throw in inches (linear measurement), not to mention the measurement is meaningless. The degree measuring tools (both for sale and ones you can make) are much more precise.

Throw accuracy is more important than you might think. The actually amount of throw typically isn't real critical, but having identical throws on say both elevator halves typically is important. For example, you probably won't notice much differance in flight if your both your ailerons move 10 degrees or 11 degrees... but you WILL notice if one moves 10 degrees and the other moves 11 degrees.

Most planes of similar type will use similar throws when measured in degrees. Inch measurements will depend upon the size of the plane, where the measurement is taken, etc. This is what makes inch measurements unfriendly. By measuring in degrees, you can measure at any part of the control surface and compare throws to other planes, regardless of scale, location of measurement, etc.

You can make a really big throw gauge by taking a protractor like what Kevlar shows, and then run it through a copier and enlarge it, or scan it and blow it up on your computer, etc. I actually draw very large protractors in autocad and print them. By very large I mean if I made a complete circle, it would have a diameter of about 3 feet.

I tape (or insert into the surface) a very fine music wire that is the indicator for my protractor gauge. It is stiff enough that it doesn't bend much but light enough that it dosen't deflect the control surface. Remember to place the center point of the protractor gauge at the hinge line.

Cheers