Scratches covered with white-wood-prepared-for-paint

[Stefano]

Good morning (here in Spain it's 9 o'clock):

 

One of my friends gave me his guitar ask me to fix the mess that he did! He stripped the body with a heat gun and he scratched the finish with a knife (!!!!!) leaving the body in a horrible condition (little scratches everywhere). Nevertheless - in order to make the mess bigger - he covered all the body with a white wood-prepared for paint. He thought that this prepared could cover the scratches but... no... it didn't!

So... what can I do in order to fix it? Have I to sand all the white-wood-prepared-for-paint (how do you say that in English?) and to fix the scratches with a wood-paste? Can I use the wood-paste directly on the white-wood-prepared-for-paint? My friend wants to paint the guitar in blue... so I don't have problems of "transparency".

 

Thank you for your help and sorry for my english,

Stefano

[Greg Mirken]

I think you are referring to 'primer', a paint type product that acts as a sealer and base for the gloss coats. If so, you can use a filler on top of the primer. Put primer over your filler again to be sure it's sealed, then shoot the color coats over that. Check that the product you use for the top coats is compatible with the primer (I'd just test on scrap).

[Stefano]

Thanx Greg Mirken! I'm very happy to know that I don't have to sand all the primer in order to fix the scratches. So... tomorrow I'll use the filler on top of the primer and then I'll put primer again. Just one question: how can I tell if the paint I use is not compatible with the primer? Thank you!

[Kerry Krishna]

Stefano, if you have not already started on the guitar, I would seriously consider giving it back to him untouched, and tell him sorry. Speaking for myself, I will not touch axes that have been 'repaired' like this and need to be fixed . They have a tendency to turn into total nightmares. It wan't your problem before, so it should not be your problem now.