Use some clear packing tape and leave a tab for easy removal. All sorts of solutions to that problem and it's just a safety feature - the magnet should hold in racing conditions.

 

I will never put magnets on my car again, I had a local shop print up some magnets for me with my numbers on them. I had them on the car for a weekend and they turned my paint cloudy. Still haven't figured out what it was, but it looks like the magnet cooked my clear coat.

 

No offense, but Pledge? Furniture polish? I have 20 coats of Zaino polymer (hence the problem with static cling numbers in the first place)...I don't see myself putting Pledge on. Can you elaborate a bit on the logic there? Maybe I'm missing it and can learn something. Always open to new stuff.

 

+1 on the Mrletter. I bought a buttload of "811"s. (not 8's and 1's, but 811 pre-spaced together). Then I cut a buttload of blank circles out of white contact paper using a dinner plate. Then you just take your numbers (for me, "811") and apply to your blank circle. Voila.

Using contact paper is perfect. No scratches, and won't let water under, and won't leave adhesive. This is also the easiest (least time-consuming) method I've found. At the end of the weekend, just rip off & throw away.

 

I've done the dinner plate method, too. The only downside is when the wife catches you tracing in the kitchen. Numbers were from the local art supply store.

 

+! on the mag numbers with the leading edge cut. Never had a problem. Paint on our 930 is still outstanding and with the new exhaust I nearly pegged it out a few times going into T17 at Sebring, meaning no "fly off" which I have experience before. Pops is also lazy with respect to keep the mags clean or straight and the like, and I clean before we hit the track.

 

Performance Products is now selling a mag number kit that has 3 magnet circles and enough numbers to set up all 3 more than once IIRC. $60 or so.

The magnets did not fog the paint, water got under them and soaked into the clear coat. I had this happen years ago on a car I had and the fogging went away on its own after a month or so.

 

The magnetic ovals / circles over at eDecals ran me $44 a pair and the numbers are 8" tall. They had all sorts of sizes...

 

I've had the same thing. If it's cool in the evenings, condensation can get under the magnet, and when the sun comes out the next day, it heats up the magnet and bakes the paint under it. I use self adhesive numbers on the windows.

 

I print out numbers on a color printer, cut them out, and adhere to the car with a sheet of clear contact paper. It leaves only a little adhesive when I do not apply it flatly, such as on the curves of my fender.

A roll of contact paper runs about $5 and will last several track days. Just fyi...it's also handy for road trips, as you can simpy peel away the road bugs when you reach your destination.

Here's a pic of it used to adhere the numbers, on all my leading edges, fenders, hood, mirrors, and fog lights. I did not bother to make it look pretty, as you will note the creases in the fenders. You can only see these close-up. However, it takes about 10 seconds to do a fender...try doing that with 1" wide painter's tape!!

 

Wow, never heard of the paint being damaged with magnetic numbers.

 

I have had the Elephant Racing magnetic track skins (now discontinued, I believe) on my car for, oh, about four years now and have not taken them off in about three years. I occasionally lift them up and wipe under them but never find any dirt under them. Never had any paint cloudiness issues in the Mid-Atlantic's humid, often-rainy, 90 degree weather.

 

I have the Elephant Racing magnetic track skin, used it once, it F#$Ked up my whole hood. Not sure how moisture gets under the magnet, but it was left on overnight with the car outside on a warm June night. I'll never use a magnet on my paint again.

YMMV

 

Not everyone will find this attractive, but I bought a roll of 3M Changeable Opaque Imaging Media (3M product no. 8522). It's a white adhesive backed material 7 mil. thick (that's thick) and it's made especially for application to vehicles so that it sticks well (rated for use up to 12 months), removes easily without residue of any sort and is quite good. I cut it into 11' x 17" pieces and run it through a color laser printer at the office. The numbers printed on it are photoshopped and it's easy to change them as an event may require. I use one set per event, usually.

 

I have used Solotime's reusable vinyl for years. Every now and then I replace them. I get a couple of years out of each set.