Waxed MDF - Should have sealed it first, what now.

[Glen Butler]

I made an outfeed table for my table saw and I thought I would be fine just waxing the MDF, but it is so porous that the wax soaks in and doesn't thoroughly seal the MDF. What can I do to seal the table now that wax has penetrated so deeply?

[Steve Jenkins]

I think you might bve stuck at this point. Shellac is about the only barrier coat that will have any chance of working but I'm not so sure that it will even work very well over all the wax. I have used raw mdf with wax for jigs and you have to put on LOTS of wax because as you discovered it will soak in. It will eventually even out though.

[Glen Butler]

How is wax removed? Maybe I could remove the film on top try the shellac

[Tony Bilello]

Cut 3/4" off the legs and stick a new piece of MDF on top and finish it any way you want.
If that is not practical. at least you got the idea that it may be easier to put a new top on.

[glenn bradley]

Before I went too far I would take a gray syntho pad or whatever and scrub the surface with mineral spirits. Don't soak it! Just dampen the pad, scrub an area, rinse the pad, squeeze it and shake it out real good and work the area again. Once you think its pretty clean, wipe it with a rag or paper towel wet with denatured alcohol. That should dry in just a minute.


Lay on some shellac, come back and check it in 30 - 40 minutes. If it dried well and doesn't rub off, treat the whole surface and move ahead. Now, if that fails you can start thinking about a new top or a layer of hardbaord l;aminated on or something else. I would try the simple fix first. Its just a little effort and might save you a bunch of time. On the upside I have shellaced and waxed MDF surfaces that take a heck of a beating and just won't quit.

My workbench however is MDF with just BLO and paste wax:

[Jim Becker]

Personally, I wouldn't worry about it. It's an outfeed table. Put more wax on it...

If you really want to remove the wax from the surface, scrub with mineral spirits. Then you can coat with shellac. If you want to use a film finish that contains polyurethane, be sure to use de-waxed shellac as your sealer.

My MDF surfaces in the shop just have BLO on them. (so does my maple bench top) I occasionally lightly sand them and reapply the oil.

[Scott Holmes]

Wax is fine for an outfeed table. Shellac wil seal the MDF wax cannot seal wood of MDF very well.

[Glen Butler]

The reason I want to seal it is so I can do some glue ups on it also. I have a couple work benches and need another. I will try Glen's method to see if I can get shellac to stick. If not I will do my glue ups until the top is ruined then replace it and do it right.

[Jim Becker]

Glen, if you keep it waxed, the glue isn't really going to stick to it any more than it will with shellac or another film finish...you're good to go!

[Tony Perrone]

Okay I give whats BLO

[Bill Rogers]

Boiled Linseed Oil