a "squeaky" question

[qball41]

I have noticed that some of my AFX non-magnatraction chassis make a squeaking sound when you first start running them. They sound like they need to be oiled and don't run very fast like there is friction. After about 5-6 laps, the squeaking goes away and they pick up speed.

What causes this, and how do you go about correcting it? I've tried adding a bit of oil, but either thats not the right solution, or I'm not putting it in the right place.

[midmoslts]

I have found over the years that some cars have a problem with the rear axel fitting tight. After you run some laps and the plastic heats up from the friction the car will start to wake up and run faster lap times. When I get a new chassis I measure the rear axel diameter and use a drill bit the same size or slightly bigger in a pin drill and run it through the hole from one side to the other. This will give you a little more clearance for the axel to rotate. Snap it back in and run it in for several laps.

I can't say for sure that what you are reporting is the same problem, but it could be. Hope it helps.

[CKR]

Where are you applying the oil? Usually a drop where the armature pokes through the bottom of the chassis will quiet it down. However they sometimes need oil under the arm's gear or rear axles. Occasionally if the brushes and comutator are dirty they will be noisy until some of the crud is burned off. They will also pick up speed then as the electricity has less resistance. It might be time to do some teardowns and clean them up. If the rear axles have any corrosion on them remove them and clean them up with a brass wire wheel and a Dremel or some metal polish.

[qball41]

[Ralphthe3rd]

:o Ruh Roh ! ...you didn't know about the armature hole on the bottom of a Pancake Chassis !? yikes !...you must not have ever opened up a Pancake chassis ? If not, man have you got some learning ahead of you :? FYI- oiling the arm bearing holes is Extremely important, so is the type of oil and how much is used. And too much is as bad as too little, as over oiling will foul the brushes which will then need cleaned. Cleaning the comm face on the arm is also important, as well as checking for brush wear and brush spring tension- especially if you are running the older Non MT A/FX chassis, which is basically just an evolution of the T-Jet Chassis, that sits lower and handles better, and the Magna Traction was just a further evolution with deeper magnets and coil spring loaded brushes.

[qball41]