Filling countersunk screw holes in MDF

[JamieB3009]

Hello,

I have installed MDF skirtings and architraves to a room and have fixed these using countersunk screws in places where the walls arent straight and adhesive isnt covering it. I have used ronseal 2 part wood filler to fill the holes and sanded back. When i came back to the holes a couple of days later they felt slightly proud around the edge of the fill compared to the rest of the frame. Is this normal and will this keep happening if i sand again? I dug one of the holes out and the filler definitely seemed to have taken as it was very hard to remove. Is this filler the best to use for MDF?

Thanks,

 

[Wayners]

If you use that 2 packs wood filler to fill holes, do it in two hits letting first set.
Also smooth off well and keep the filler off wood surfaces as much as you can. You need to keep sanding to a minimum so fill it tidy. Take your time.
it's tempting to fill proud with blobs of filler, but don't.
Glue sandpaper to blocks of wood so you keep surface flat when sanding.

120 grade and 180 grade sandpaper