Veneering both sides of MDF

Question:

I’m building an entertainment center and using 10 mil paperbacked Walnut veneer over MDF. I have seen DITY advice on the Internet saying that it’s necessary to veneer both sides of the MDF. I would like to avoid doing it, given the extra cost involved and the fact the back of the entertainment center will never be viewed. Is it necessary to veneer both sides? What might happen if I don’t do it?

Answer:

It is absolutely necessary to veneer both sides of any substrate to “balance” the panel. If one side of a panel is left exposed, it will absorb ambient moisture at a different rate than the side that is veneered. This unbalanced situation will cause the panel to bow or crown and the problems associated with working with panels that aren’t flat should be obvious.

The answer is to veneer the backs of these panels with a backer sheet, not the expensive walnut veneer that you’re using on the face. Backer sheets may be any wood veneer of lower grade or seconds that aren’t suitable to be sold as first quality. Because these aren’t seen, the flaws or defects aren’t a factor. In short, it’s well worth the investment of a few more dollars to insure a stable and longer lasting veneer panel. Good luck !

Follow-up Question:

I just read the suggestion that a backing veneer should be used on the back face of MDF panels when using wood veneer on the exposed face. My question is whether this backing veneer would be required if using a PSA pre-glued veneer. Is a PSA adhered backing veneer product available? I did not see one on the price list under PSA veneers. Thanks

Answer:

The answer is “yes”, you should still use a balance backer sheet with the PSA veneer. It’s not a matter of how the veneer is adhered, but more a matter of “balancing” the panel so changes in moisture conditions and temperature won’t adversely effect the stability of the panel.

It’s not critical to use the exact same veneer on a panel back, but it is critical to use something that will even the rate at which the panel absorbs moisture on both sides. You can use a cheaper veneer as a backer and there are different types of impregnated paper backers that are effective. In any case, it’s always better to spend a few extra bucks and do it right rather than deal with the inevitable problems later.

Oakwood Veneer Tech Support