how to detect filler under paint

[anonymous-user]

I have rust bubbles on both rear arches and before I get the car into the shop to have it fixed, (and properly with actually metal and welding!), I want to find out if there is any filler in that area. In other words, if the previous owner had rust problems before and did a bodge job on it.

My garage doesn't have such a machine. I guess I am looking for somewhere that has one of these machines...
http://www.defelsko.com/applications/paintmeter/au...

any advice for someone in West London who can do this?

[RedCarsAnonymous]

Small magnet & a bit of tape/cloth over the end to protect the paint (dab on, don't sweep) worked for me on used cars

[anonymous-user]

thanks, I'll give that a go. Sometimes hi-tech is not always best.

[TallPaul]

An experienced eye should be able to look at the bubbling and tell you if its filler or just rust. I've got to ask though, if you're going to get it welded anyway (and as the paint is ground away, filler will be obvious), why are you so keen to know beforehand?

[HumbleJim]

I use a Wallace and Gromit fridge magnet (the one on the motorcycle combination) Wallace's head has dropped off but still works well sorting steel from filler.

[anonymous-user]

many thanks for the answers - I wanted to know because the seller before me had used filler on parts of the car (which I have subsequently removed and had welded properly) and then resprayed the car. So I want to get an idea of where else he might have done this. I think I've found it all though. Which is a relief.