MDF Core Showing through Thin Veneer
Crossbanding with another veneer first is the way to keep core materials from telegraphing through. August 29, 2014
Question
I am making a box which will be 0.60mm sycamore veneer over a MDF core. The box will have a strip of solid sycamore at the base and at the lid separation, so prior to veneering there will be a sandwich of MDF and sycamore. I have done a test and after veneering sanded the face until smooth - but when I applied the finish to the sample I could see the MDF core ghost through slightly. Could I paint the core prior to veneering? If so, which glue would work best with what paint or are there any other options?
Forum Responses
(Veneer Forum)
From contributor J:
Use thicker veneer or solid if the design allows.
From the original questioner:
Not possible - it needs to be ripple sycamore which for a good figure is only available in veneer.
From contributor J:
You could try a light-colored (Baltic birch) substrate instead of MDF, but I think you may have to live with it not being perfectly flat (don't sand it so much).
From Contributor K:
You can try priming the MDF to make it light in color. When you veneer over that and finish it the brown won't be there to ghost through the veneer.
From the original questioner:
Yes that's what I want to do but which primer will still take the glue well?
From contributor O:
This would be a good place to use a crossband. Either a light-colored veneer like Maple running perpendicular to your Sycamore face or a synthetic crossband like PolyBak (they make it in an Ivory color). I would not try gluing to paint or primer.
From Contributor C:
As veneers get thinner we see this more and more. We sometimes press a light colored veneering paper to the core first, I believe it's .010-,015" thick. Problem solved. Whenever we can we prefer to use flake board as it is lighter in color, but it's not always possible.
From the original questioner:
I had been thinking about using a backing veneer run at 90 to the face veneer but was hoping for a quicker method. I’m not too sure where to get the veneering paper from in the UK. Can standard copy paper work?
From Contributor K:
I stand corrected. I shamefully retract my priming the mdf idea. I did not consider the adhesion problems only the color change problems. Cross banding is the best solution. It would be just as labor intensive as gluing a layer of paper beneath the veneer and you won't run the risk of having the paper show at the edges.
From Contributor C:
The issue with regular paper is that it can separate. Try checking cabinet shop or their suppliers for good quality laminate backer. It should be stiff, that means it was pressed or annealed for hardness when manufactured.
From the original questioner:
Thanks for all the help. I think the crossband is the way. It’s extra labor but worth it.
From contributor J:
Why don't you just get some thicker veneer? If the veneer is that paper thin you are going to have adhesive bleed-through problems and sand-through problems anyway.
From the original questioner:
I can't get ripple sycamore veneer any thicker than .6mm.
