I just got a used SCX Telefonica Minardi for $15.  Used, but ran well.  It had two problems, a cracked front wing and crud on the braids.  The braids were so bad that they begged to have an article written about them.  Now, most normal people would just change the braids, but I hate working on SCX braids and besides, these looked in great shape except for the crud and the color.

They actually looked worse than this first picture, but the scanner made the copper color stand out.

It is a simple procedure to restore the braids without removing them.

Step #1: Pop the guide shoe off and drop it into something like an old 35 mm film container and cover it with solvent.  In this case I used Goo Gone but WD-40 works just as well.   Shake it a couple of times, "set it and forget it." Now I feel like a Ronco commercial.

Step #2: Remove it from the solvent bath  and wipe down the braids, guide and guide stem.  You would be amazed at ho much crud can build up on the whole mechanism. Let it dry.  Repeat if crud is still in abundance.

Step #3: Get out your Dremel tool and put in the wire brush and polish the braids.  Don't just do the part that hits the track but also the braid that rubs against the two little prongs on the top that make the connection to the motor.  Clean them as well with emery paper.

Here is what they look like after the thorough cleansing.

Remember your car is a total package and the less of it you work on, the harder it is to track down problems.  The most often encountered problems deal with electrical connection.

Dan