Mdf window cill

Oct 04, 2008 6 Replies

I fitted and mdf cill to the kitchen window a couple of years ago. This morning I noticed (behind some strategically placed clutter - wondered why it was there!) that a small (2 cm stretch of the 'nose' has had the paint chipped off and is a little swollen. I'd rather not replace the whole board (could be a right pain with trims etc) so I thought I'd see if I can repair it. My first thought was to route a new edge, but the router would foul on the wall exactly at the end where the problem is.



It should be pretty simple to carve back to good stuff leaving a shallow-ish groove along the top edge of the nose, but what then? Is there something particularly good for filling mdf? Should I prime/ paint it before building it up (though it might not give a good surface for adhesion)? Or should I cut out a bigger section and replace with a new piece of the nosing? (Might be tricky to get dead right of course).



I'm sure someone has had this problem before, among all you knowledgeable people, so any tips warmly received.



(Why do I have visions of angle grinders, SDS chisels and car body filler?)


MDF is not the be all and end all of other materials. Use real wood and stain it.

Best advice is to remove the MDF window board and replace it with timber - water could be affecting the MDF through the paint chip, which is why it is swelling.

Another method - if you must keep the MDF that is - is to fit a UPVC window board. This can be stuck down using something like No-Nails afer rubbing down the cill with glasspaper to get a key (plus removing any ingrained grease/fats).

Unbeliever

This is ideal for car body filler.

Sand back and repaint. It sounds like its got wet and stayed wet. The one thing MDF does NOT like.

what use was that post??? the op wants to repair it, not faf about replacing it refilling it staining it to the op I would be tempted just to rub it down and fill it

What? Installing a uPVC window board over an MDF one?

Thats going to look really good...

Somehow I thought car body filler might be the thing!

Thing is, it's only a small issue just now, so if I can catch it quick I shouldn't have to go to the trouble of dismantling half the kitchen to replace it with an exotic piece of hardwood!

I guess the lesson is to give mdf plenty of coats of paint when it's anywhere near water...

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required