MDF paint touch up?

[DIYfronts]

Hello, I am putting together a sort of desk, and I have two desktop cabinets made from MDF which have already been painted in black for me. I am attaching an MDF shelf to the top of it myself, which I am planning to paint black to match.

I didn't want to paint the cabinets myself because they are a tricky shape and it wouldnt be easy to disassemble and reassemble. However, when I picked the cabinets up from the person who made them, supposedly when the paint was drying on a really hot day, dust etc got stuck to it. There are some little areas of the cabinet surface, where you can see odd white coloured finger prints and a few other little patches and blemishes. There is also a small fingernail-width chip where the paint has come off.

My question is this - whilst I'm painting the MDF shelf to match, is it ok to "touch up" the blemished parts of the cabinet at the same time? (I'm using black spray paint).

Or, as I fear I'll be told, would i need to sand/prepare/do a proper job on the MDF cabinet to fix up the strange dusty bits and fingerprints?

Thanks in advance!!!

E

 

[joe-90]

You've got nothing to lose by trying to spray over it. If you sand it you'll have to do the whole lot again.

 

[DIYfronts]

Yeah , that was my concern, I really don't want to do it all again

Although, I thought that maybe spraying straight over already-painted MDF would either leave it looking patchy, or otherwise not adhere properly... what would be the 'standard' practice in this scenario?

Cheers