Painting MDF doors

[Donkii]

Hi guys,

I am decorating my new house, Converted bungalow, and have came up against a very annoying problem. Upstairs we have have some small doors on the walls for access to storage space in the eves, these doors are made of MDF and have a tapered edge. The previous owner just emulsioned over them with a roller the same colour as the walls. We have redone the maine bedroom upstairs and I wanted to put a satinwood finish on the doors the same colour as the walls.

So I used a combi primer and undercoat (waterbased) as advised by B&Q. I done a few coats and sanded lightly to get a nice smooth finish. The problem is I have now applied to coats of satinwood to the outer side and the finish is awful, almost like in some places the paint is being obsorbed.... I thought the combi primer/undercoat would sort this?

Just as an experiment I have put some oil based undercoat on the back of one of the doors to see how that turned out.... will this give me a better finish topcoat or is MDF just bad to paint?

Thanks in advance.

Ian

 

[misterhelpful]

Always best to use oil based undercoat with oil based topcoat - assuming you have oil based satinwood.
The surface was already sealed with emulsion, so I doubt the mdf is absorbing it in patches. It must be down to the primer/undercoat or it may be that you have missed patches with the topcoat or not applied it evenly, which is quite easy when painting white on white.

 

[Donkii]

Thanks mate,

Its not an oil based satinwood, I dont think, its a natural wicker colour. I had to get it mixed in B&Q to match the walls. Can I apply it over the oil based undercoad if I give the under coat a gentle sanding?

 

[misterhelpful]

Yes, oil based undercoat is suitable for nearly every topcoat.

Good luck with it.