# mdf



## james33 (10 Apr 2008)

hi all. I need to finish a cupboard in water based eggshell (farrow and ball) and was wondering what's the best way to stop the edges 'furring' up.
I've tried applying loads of coats but cannot get a smooth finish on the cut edges.


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## BradNaylor (11 Apr 2008)

It sounds like the cupboard is made from normal or 'fluffy' MDF - the beige coloured stuff.

Next time use Moisture-Resistant MDF. It comes in a green colour and it gives much better results when you machine it. The edges are much harder and crisper and take a finish much easier.

Travis Perkins stock it but don't pay list price. Haggle!

As for your current problem, someone with knowledge of water-based finishes will be able to help. I've given up on them and have gone back to AC paints.


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## jasonB (11 Apr 2008)

Did you use any form of primer before the eggshell?

You should be able to cut back the rough edges with 180g paper to get them smooth and then give a final coat, tend to use the oil based myself over a waterbased primer/undercoat.

Jason


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## aurrida (12 Apr 2008)

i would normally sand down to a fine 600 grade till it starts to look burnished. have used water based primer. sand back again with fine and re coated sometimes three times before water based top coats and water based lac. i use a mini sponge roller, gives a slightly textured plastic coated finish, durable too. dont be too alarmed how rough it feels after primer, ok after re sanding.


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## oompedoomp (12 May 2008)

Hi
Been doing this for 2 years now. Once you have machined your mdf spray the raw grain with a pre-catalysed lacquer. Dry, rub down with 120 grit and apply another coat. Dry. Rub down with 240 grit and then prime. Faultless.

Si


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## the_g_ster (25 May 2008)

can you spray pre cat at home then with hvlp and outside?


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## Sgian Dubh (26 May 2008)

james33":ibd98mbr said:


> hi all. what's the best way to stop the edges 'furring' up ... cannot get a smooth finish on the cut edges.



There are a few tricks you can try, and most involve filling the exposed edges. Some swear by painting on thinned out PVA glue. I like to take water based wood stopping, thin it to a slop, and rub it hard into the edges. I've also done a similar technique using plaster based products, eg, Polyfilla wall repair stuff. It's coarser and grittier than wood stopper, but it does work. 

Other people I know like to use the flammable solvent based wood fillers, but I find they dry too fast to get worked into the voids properly, and that's why I stick to the water based stuff. I haven't ever had a problem with the edge pooching up fat because of the water causing the wood fibres to swell. Some people say they've experienced this, but I haven't.

Take your pick from any of the above solutions and give it a go. One should work for you if you do it right. 

Anyway, whichever means you use to choke the voids in the edge, once you've got that accomplished you sand it smooth using something like, 100, 120, 150 or 180 grit paper, depending how smooth a surface you need. Next apply you primer and top coats. This generally works fine for brushed or rolled paint finishes, but isn't so good for clear wood finishes. For this there are MDF primers that can be brushed or sprayed on, but they're not relevant to your question. 

And now I've just noticed this question was posed several weeks ago, so my suggestions are probably useless james, but maybe somone else might find these tricks helpful. Slainte.


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## oompedoomp (26 May 2008)

the_g_ster":1mngj1ey said:


> can you spray pre cat at home then with hvlp and outside?



Yes. Usual H&S common sense rules apply. I have to say that I have found this the quickest and cheapest method of prepping furry cut mdf edges. If filler is used, you will need to ensure a completely even and level finished surface. I do not need this check with pre-cat as I am only 'smoothing' not sanding. 

I am a kitchen furniture maker to high end markets. No complaints yet!

S


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## the_g_ster (29 May 2008)

Where do you get pre car lac for this from? Suitable suppliers?

As a general interest point I sprayed some farrow and ball oil onto MR MDF this weekend and the finish is awesome, 6 coats in total, 2 international sealer, 2 undercoat, and 2 oil eggshell. It looks like somebody else did it, not me, dead pleased, so got the bug now.

G


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## oompedoomp (29 May 2008)

I use a pre catalysed lacquer supplied by Trimite. Not sure if they supply the US but I guess you have a similar product.

S


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