# Staining & varnishing MDF ??????????



## Anonymous (8 Nov 2003)

Hi 

i've been asked to do a small job for a friend. Basically there cat scratches the front arm of there set-ee and chair. They have asked me if i can make a small wooden L shaped box to screw on the front of the chair etc to stop the cat ripping the chairs even more. 
i've thought of using mdf because it will hold out well to future scratch marks from the cat. I would like to stain it quite dark and then use a tuff varnish on top. 
Is this possible with MDF? 

What brands do you recommend? 

What is the method for staining and varnishing MDF


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## Scrit (8 Nov 2003)

coggy":4b9mi9md said:


> I would like to stain it quite dark and then use a tuff varnish on top.
> Is this possible with MDF?



Yes it is easy to do (just look at the profiled edges of modern furniture such as pub tables, etc. to see what I mean). Main thing to remember about MDF is that it is fundamentally a sophisticated blotting paper and will absorb stain in a like manner - especially the cut ends which will absorb lots of stain and go very dark unless you dilute the stain considerably. I have to admit to only ever staining the ends of pieces, but I would have thought that to get an even colour would involve some face sanding and a major amount of juggling to achieve a match. It may be easier to use a mitre joint, thus hiding any cut ends grain. Other than that, waterstains work well as do any number of polyurethane lacquers, acrylics, etc. You'll need to seal the stain before lacquering unless you want to pour finish into it. A well cut clear french polish or well-diluted final finish works well for this, but you may need to test that your top coat will "take" over the top (on a piece of scrap) firstbb.



coggy":4b9mi9md said:


> What brands do you recommend?



Rustins do a good high solids water-based acrylic lacquer with about 30-35% sheen (a bit glossier than eggshell) which comes in smallish cans. Best stuff I've ever used is Dulux water-based acrylic designed for dance floors - but it only comes in gallons (well, 5 litres, actually) at about £12/litre. Water-based products are better for the environment, but almost as importantly they are much easier to clean-up (just wash out your tools with water) and don't smell half as bad as the solvent-based stuff. Use a man-made fibre brush, not a bristle brush, and avoid steel wool (water-based finishes can cause stray pieces of steel wool left on the surface to rust), there are fine Scotchbrite-type pads out there (one source is Machine Mart) which do a good job of denibbing between coats. If you do use a water-based finish don't be put off by the blue-grey some of them take on whilst they are drying or the orange peel effect that spraying produces. After drying overnight they look great. 

Alternatively suggest to your friends that Chester Zoo sell lion dung by the kilo - it's supposed to keep rampant cats at bay! :lol: :wink: 

Good luck

Scrit


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## Anonymous (8 Nov 2003)

Many thanks for that

I will take that advice


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## Anonymous (17 Nov 2003)

Coggy

Personally, I think the replies you got at this address
http://www.woodworkforums.ubeaut.co...?s=072548e0977e9a6953ec506b38047196&forumid=9
were much more on the mark!


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## Scrit (18 Nov 2003)

For those who aren't aware cas are regarded as a pest in Australia....

Come to think of it they are also regarded as a pest in my workshop...

Scrit

PS - One commercial guy I know does MDFedges by loading a spray gun with a clear cellulose lacquer mixed with an alcohol stain to seal and tint the MDF in one pass. He then rubs down and builds with multiple coats of tinted lacquer until the desired tone is reached.


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