Hi NC

First, check to see if the rods are binding themselves. To do this, disconnect them from the control surface and the servo, and move the rod back and forth. They should move very freely. If not, you should work on getting them to do so. The path from the servo to the control surface should be as straight as possible, with all bends happening as smoothly as possible.

Next, I would connect the rods to the control surfaces, and try moving them again, and see if they increase the friction dramatically. If so, check out your hinges to make sure that they aren't binding, and get the control surfaces to move freely.

Now with all of that done, you can connect the servos. When you do this, first center the servo with your transmitter, and place the servo arm so that it is centered for the particular throw of the surface you're trying to move. The idea is to have equal travel in both directions, and when the control is centered, the control surface is in it's neutral position. Depending on your equipment, you can adjust the travel length for each direction, but the end results is at both ends of travel, the servo shouldn't bind, or try to move the control surface farther than it physically can, if you know what I mean.

Sometimes you have to play with this stuff quite a bit. My suggestion to you is after you check all of this stuff, find a local club and bring the plane out with you, and ask some of the more experienced flyers to check it out for you. They'll be able to point out any problems with the linkage you might have.