Waterborne GF Topcoat + veneer = lifting

Scorpion

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I have built some cabinet doors that have Center panels that are constructed out of MDF with Oak veneer. I've stained them black and have clear coated one side and I'm finding that, given my clearcoat process, the veneer is lifting in spots. When searching around the Internet I found that I must be careful as to how much of the water-based clear I put down before the veneer is sealed. I'm good with that only at 4 coats in, the veneer is still lifting. It seems that the oak is having a hard time sealing because of the grain.  Is there a step I'm skipping?

I'm using General Finishes waterborne Top Coat btw. 

Thanks
 
I've never had the problem of veneers living.

You could try Seal Coat, shellac or Crystalac clear grain filler to seal the veneer.

Tom
 
tjbnwi said:
I've never had the problem of veneers living.

You could try Seal Coat, shellac or Crystalac clear grain filler to seal the veneer.

Tom

Maybe lifting isn't the correct term.  Bubbling or swelling within the grain?  I used 3M PSA veneer btw.

Crystalac can be used over stain, can Seal Coat?  I still need to finish with GF Top Coat because the inside of the doors already have been and so has the rest of the cabinets.  I'll need to seal over the stain or sand it and re-stain and then shoot the GF over the top.

Thanks for your help.
 
Seal Coat will accept any top coat and works very well over stain.

Tom
 
Scorpion said:
Maybe lifting isn't the correct term.  Bubbling or swelling within the grain?  I used 3M PSA veneer btw.

I have had bubbling of the veneer on commercially manufactured panels, mostly oak and Ash. I have only had this problem while flooding the surface with stain.
I usually ask and get a discount on these panels. I am not sure, but I suspect the bubbling occurs because the glue was not correctly applied, there was an air pocket or the water in the stain dissolves the glue used to adhere the veneer to the chip board.
To correct the bubbles, I score down the middle of the bubble with a sharp knife and then squeeze in a little CA glue and then push the bubble flat with a roller. It usually works but if you put too much CA under the bubble it can make a mess.
In your case it sounds like the PSA didn't properly adhere to the substrate.
Tim
 
I have had problems with ash burl veneer adhereing to mdf.  I sanded the mdf prior to using cold press glue and always had areas bubble up. The last 2 panels of a 8 panel job turned out great when I switched to birch ply instead of mdf, everything else was the same. I used 2ply birch veneers as backing and they never bubbled either with the mdf or the ply.  Raw veneer and some mdf don't mix is my only answer.
 
Ah crap...sounds like picked the wrong substrate.  coulda used Baltic birch but specifically went after MDF because it's so stable.  Looks like it's a learning moment for me.  I appreciate them but only when looking back.

Thanks guys.  I'll try Seal Coat to minimize during too coat application...hopefully.
 
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