Originally Posted by Doc
AdamR-NY, if you get water on the edges of MDF it will act like a sponge and swell up and quite quickly.
That is also what makes the edges difficult to paint unless you seal first as Ken mentions - because you can easily waste most of your expensive paint as it gets slurped up without actually giving you a finish.
Shellac is also really useful for doing the same thing - it will seal and can be sanded smooth as required before you paint/finish.
Ken, they are awesome looking planes there, my friend