Repairing MDF shelf finish


Does anyone have a good technique for repairing the plastic finish on an MDF shelf?

I have a SolidSteel rack and one of the shelves has a ding in a very noticeable place. The plastic coating has been knocked off, but the underlying particleboard is OK.

I'm thinking there must be some product that would adhere to the particleboard and could be smoothed in and made to match the existing plastic, and then painted black when it hardens. Any suggestions?

Thanks - David
magister
I use brown paste shoe polish on wood scratches and marks. Use a rag and rub it in until it blends in with you color.
Putting your question into Google, this is what I found.

Repair

Any help with your situation ?
Automtive glazing putty. It's often used to fill the cut edges of MDF which are too porous to paint.
Thanks, Albert; that looks like what I need.

Musical Therapy's idea idea of using shoe polish is clever, cheap, and would work for natural wood finishes, but in this case I need to rebuild the hard plastic layer on top of the fiberboard.
Plastic wood should work also with a magic marker for color. Of course you could also turn the shelf around if the chip is on the front.
Thanks for two good ideas. I'll check out the glazing putty, which I'm not familiar with. For some reason I've never been fond of plastic wood, but it could work here. Unfortunately, the shelves on SolidSteel racks only go one way, and the chip is on the front top.
Yes, I know what you mean about them only going one way. Don't they have holes that line up on the bottom? Can't these be re-drilled?
I don't have access to a drill press, and I woulnd't dare redrill them without one. If the holes are not identical in depth, and straight, the shelf won't ever be level and solidly supported. If I can't get a goodlooking repair I might have to go this route.