HOW TO FIX BLISTERED WOOD VENEER

This question from Mark was emailed to me recently...

"I wonder if I could ask a question… - I’ve spent some time using a paint remover on a table top and it has blistered a little bit. Is there anything I can do to get rid of this?"

I think the blistering has probably been caused by the stripper.

Most modern strippers are water-based and this may lead to problems when stripping old veneered surfaces:

Any imperfections in the veneer; small holes, splits, cracks, old knots, tears, may potentially allow the water based stripper to penetrate under the veneer. And because water based strippers take a long time to work, the water contained within it may dissolve the water based glue that holds the veneer down, resulting in bubbles on the surface. I think this is what has happened to your piece of work.

To attempt to repair this:

 Antique veneers are normally glued down with a water based, heat activated glue. By introducing heat the glue will soften and revert to a liquid.

*You can see me using this glue in many of our Youtube videos.

• First of all try ironing the bubbles back down. Using the tip of a warm iron (not burning hot) and a piece of brown paper (or thin cloth) as a barrier between the iron and the wood. With increasing pressure in small circular motions, rub the iron over the bubbled veneer, being careful not to get it too hot.
  
  Trade tip*
  If the above is successful at flattening the veneer, another top tip is to immediately rub a flat, cold, heavy object over the surface, cooling the glue down to set it and fix the veneer in place. We use an old fashioned smoothing iron and we also have a small block of steel. But you can improvise with anything you have to hand.
  
  If you have them, and you can access the right spot, G-cramps or F-clamps will also be a great advantage.
• Sometimes these blisters are stubborn and refuse to flatten. This is where the use of a scalpel or craft knife is necessary. - Make one or two small incisions in the side of the bubble and try the Iron method again. If this does not work then you can introduce new glue to the incision with a cocktail stick. We would use hot hide (hyde) glue here in the workshop but you are highly unlikely to have this at hand. So your best choice here is to use a super glue with an activator. But be very careful.
  
  The Method:
  You may need to trim a little bit of the veneer off to make it fit flat to the surface before glueing
  
  Carefully using a cocktail stick, force the superglue into the cavity. Once you have enough in there, spray the activator directly on the surface and IMMEDIATELY force the veneer down flat using a flat piece of wood or steel with pressure, but keep your flattening device moving to prevent it from sticking to the surface. Try to wipe away any excess or squeezed out glue very quickly with a cloth.
  
  This second method is final. It cannot be reversed. I do not advise using this method on period, valuable antiques. But let's be realistic here, the likelihood of someone attempting this on period antiques is slim. But it will allow you to move on with your restoration work.
  
  If there are any remaining gaps or holes in the veneer you can fill with a wax filler after you have stained and sealed or just sealed the wood.
  
  *You could try method 2 using a cold hide glue, (Titebond) but this would mean leaving a weight / pressure on the repair for 48 hrs or more.