When to throw clay bar away?

[paulw123]

So i used maguires clay bar kit for ist time at the weekend, turning it over a few times. Lots of black tar came off the paint.
How do you know when the clay bar has had it & needs replacing?

[RedRobin]

.
When it stops picking contaminents off and gets so that there's no clean parts when you knead it and fold it over a few times.

Of course, some folks will throw it away earlier than others. I use one small piece at a time (also Meg's).

[JP6]

I use a small bit at a time, and only use that small bit once per clay session.

[Frodo-anni]

The megs bar and most others is possible to cut into 3. If you ever drop it on the floor, always throw it away never re-use on the paint work. I tend to use one of the pieces once on the car, then keep for doing wheels with later.

[garrardrj]

What does a clay bar do that a good polish doesn't ?

[Saintsteve]

What does a clay bar do that a good polish doesn't ?

It takes all the bonded contaminants out of the paint, so when you polish, you get a better finish 

[stealthwolf]

For tar, you're better off using a tar remover since a clay bar will just push it around.

As above, divide the bar into 2-3 pieces. I use a piece once for bodywork and depending on how it looks, either chuck it or save it for bits like the wheels.

You shouldn't need to clay more than twice a year.

[Horatio]

works good on glass as well 

[Tortaruga]

Is it ok to clay the diamond cut face of monza alloys?

[Scottymon]

Should be fine, but what I would suggest is to run your hand softly over the the alloys before hand to see if there are any areas that have a slight nick to the lacquer... then avoid those directly with the clay bar, as you know once the lacquer has been chipped / removed the white worm process will begin :(

[paulw123]

thanks chaps, i should of asked you lot first, as i did'nt think to cut it into 3, but used the whole bar    , then i kind of folded it over and thought-- i wonder when this has had it, don't want to harm the paint by rubbing contaminates into good paint 

[scooba]

I used my Megs kit for the first time today on our BMW Coupe. last time i tried it it seamed to stick to the paint this time i used loads off spray and it worked a treat I onld done the boot and rear bumper the I polished it with some Megs wax ,I am really pleased with what I achieved ,Tomorrow eve I intend doing the hood or sills or both.

When you clay glass do you just apply it like you would to paint

What about the lube im sure I read some where you can use soapy water ?

TIA