veneering question

[zapdafish]

I have some mdf panels I am going to experiment with veneering on. If I want to edge them with hardwood, which do I do first? veneer the panel then add hardwood edging or edge first then veneer over both. both veneer and edge wood are the same species.

 

[Martin Roper]

I have never done this, but if I was trying to avoid a visible seam where the veneer meets the edging, I'd put the veneer on last.

 

[dancam]

+1 on veneer last.

 

[JNCarr]

Definitely veneer last.

 

[Kelly]

Veneer last, but that hardwood edge should be no more than 1/8”. Otherwise it will show under the veneer. Unless you are using a 2 ply veneer skin.

 

[Matt Furjanic]

I do this all the time. Best practice is to put on the hardwood edges first. Doesn’t matter how wide it is. May want to make it plenty wide if you want to rout the edges afterwards. Sand the piece making it as flat as possible at the glue lines. Put on two layers of veneer with the grain of the top veneer perpendicular (or at least 45 degrees) to the first layer of veneer - this prevents the glue line from being visible through the veneer.
Another trick is to use just one layer of veneer, then rout an inlay channel above the glue lines and put a stringing or an inlaybanding in there.

This is a sapele veneered plywood top with holly stringing hiding the glue line. Note the rounded over edges. The wide solid perimeter allows tor beading of the edges. Matt…

 

[Bernhard]

As everyone said, veneer last. I have never double veneered, imho it causes other issues with balance.
One other item to consider is the wood species. I also match the veneer glue color to the veneer. For darker wood (i.e. walnut) I use dark-tinted veneer glue; not only helps with hiding the difference in the substrate but also helps in case of bleed thru. I generally only veneer with darker wood or closed grain wood and have not had any issue (walnut, cherry, maple, anigre). For solid edging I usually have at least 12 mm (1/2") thick bands (thicker if there will be some profile routed later): Makes glue up much easier. A lipping planer followed by careful sanding for a flat panel is next. Some of the glue lines are due to the environment: Adding glue to MDF/solid edging will cause some minute differential swelling, I let the clue cure for at least one day before planing/final sanding. Also, both substartes should be acclimated before final sanding/veneering. I had one incident where I veneered an edgebanded panel while the AC in my shop was out for a couple of days: That panel showed gluelines a bit; likely due to the difference in moisture uptake/swelling of the 2 substartes followed by the drop in humidity after the AC worked again.
And lastly, pressure during veneering: Vacuum veneering is fail save since the pressure is limited to atmospheric pressure. But using clamps/cauls/hydaulic presses can exert much higher forces and can actually dent the material, if a excessive force runs over a glue line, then it will show.
hope that helps.
Bernhard