Put some wood glue in a syringe with a very small needle. Carefully make a hole with the needle. Try to place the hole in one of the wood-grain cracks. Use a warm iron to squeeze out as much air as possible working from the farthest edges of the air pocket to the hole. The warm iron may heat the glue that is already there enough to cause the veneer to reseal the underlying material. If not, use the syringe to insert a small amount of glue. Use the warm iron to work the glue into the pocket and set the glue at the same time. Leave the iron or something else heavy on the repair location for a while to allow the repair to set. Once the air pocket is gone, you can use a sharp crayon that matches the wood to fill the hole. I have done this many times. Be careful with the heat. If your iron is too hot, try putting an old towel between the iron and the repair spot. I use a clean rag to quickly rub over the crayon causing friction to aid in working it into the hole. The whole job will cost about 20 EUR plus time spent.
This is awesome, thank you! Would it make any difference If I elaborate and say that it’s hard? As in I can’t flatten it by pressing it down with my finger. You seem acquainted with the issue so I’m guessing that’s how it usually is or that it doesn’t matter and the same methodology still applies?
If you can not press down the bubble it is either a flaw (has it always been there?) or a small hole that allowed some water to seep in and expand the underlying material (MDF). Either way this is non-fixable without removing the veneer and refinishing, or sanding smooth and apply a new veneer. You can still try the iron trick to see if it flattens with a small amount of heat.
Solid wood doesn’t bubble like that. I’ve got some cheap wood look particle board dressers and if you leave a cup on it you’re screwed. Looks like you’ve got a table like that, really messed up to make a table out of something that can’t get spills on.
Unless there is a foreign object like a bug or splinter of wood between the veneer and the underlying material, the bulge is usually the glue that can be heated and vented through the needle hole. If it is a solid object, it can likely be removed by making a slit in the veneer following the grain of the wood. Use a new blade in a razor knife. Be careful to keep the slit small. Then dig out the obstruction until the veneer lays flat. Use the syringe to apply a small amount of glue under the veneer. Finnish up with the iron, weight and crayon. As I said before, it is going to take some time. Be patient and careful. You can do it.
Make a tiny hole, and cover it with a cloth and iron it, if it didn’t work, try injecting wood glue into the hole.
Stick it with a pin and use a roller or roll your thumb over it from the outside to the middle of the bubble. I used to work in a print and vinyl shop and that’s how we did it.
Do you have questions related to home improvement?