Checking for alignment problems with your hands

Here's a tip from a reader this week. How to detect alignment problems early using a simple hand rub test on your tyres. Specifically feathering due to improper toe-in alignment. What's neat about this test is that it requires no tools other than perhaps a damp rag.
This test will detect feathered tires long before you can spot any feathering visually and takes about a minute to check all four tyres.
- Take the damp rag, and clean mud, debris, etc from the top area of the tyre's tread portion that you will test. (You don't have to wait for the tyre to dry.) If the tyre is already clean, you can skip this step.
- Stand with the tyre directly in front of you. Using your preferred hand, open your hand so it is flat. Place your hand on top of the tyre.
- Now rub the tyre applying moderate pressure. First push your hand away from you, moving it across the tyre tread, then draw your hand back towards you. Do this a few times so have a good "feel" of the tyre's surface.
- Repeat with the three other tyres.
An UNFEATHERED tire will feel pretty much the same in both directions of your hand's travel. You will be able to feel the edge of each tread as your hand slides over it, so it won't feel perfectly smooth, but it won't feel like you are rubbing over a knife blade either. The key point is the tyre tread surface will feel the same in both directions.
A tyre that is feathered due to excessive toe-out will have a sharp outside edge on each tread block, and the inside edge of each tread block will be excessively worn down, thus you will feel the sharp edge as you push your hand away, and the tread will feel smooth as you draw your hand towards you. The tyre surface will will different on the push stroke than it does on the pull stroke. Push = sharp. Pull = smooth.
A tyre that is feathered due to excessive toe-in will have a sharp inside edge on each tread block, and the outside edge of each tread block will be excessively worn down, thus you will feel the sharp edge as you pull your hand towards you, and the tread will feel smooth as you push your hand away from you. The tyre surface will will different on the push stroke than it does on the pull stroke. Push = smooth. Pull = sharp.
If a pair of tyres become toe misaligned by say 3 millimeters after a tyre hits an object, you will be able to detect the resulting feathering using this method within a few hundred miles after the event, long before any serious damage to the tread occurs.