The Soft Film Problem in the Wood Finishing.

The soft finishing layer is finishing with too soft film; when the finishing is touched or under physical pressure, it develops marks, print marks, finger marks, or other marks. In the very bad problem, the finishing layer could stick to the things put on. If the furniture is packed and wrapped with foam or paper, then the form mark appears on the finish surface or the foam is stuck to the finishing. A soft finishing layer is a serious problem since it makes the furniture cannot fulfill its functions. No matter how good the furniture is, it will be useless if it cannot hold the things put on it. 

A soft finishing layer indicated a failure in the finishing process. It could be from the wrong process, the bad quality material, or the wrong material choice. This problem is quite difficult to fix; it most often has to be stripped off and refinished with the right process and the right finishing materials.  The soft finishing layer is mainly caused by 2 things: the finish layer that is not perfectly dry and the bad quality of finishing materials. To avoid this problem, you need to make sure to use only good-quality material and do the proper finish.

The poor quality of the material, instead of low-quality material (mostly because the price is too cheap), can also be due to several other reasons, such as material that has expired, inappropriate mixing, inappropriate thinner, or mixed material that has already passed its pot life.

The second reason is because the layer is not fully dry, which can be caused by several reasons, such as too thick coating layers, too rush in the process, the incorrect mixing ratio for catalyzed coating, and the incorrect thinner to reduce the coating.

soft coating at the table

Here are some tips to avoid the soft finishing layer.

The soft finishing layer is a big problem. If it happens, it will be costly to repair and fix it. The best option is to follow the correct process to avoid this problem. Here some guide to avoid this problem

• Provide sufficient drying time at each step in the finishing process.

Every finishing material requires a certain time to dry. The finishing materials, which are dry with chemical reactions, need certain time to ensure their chemical reactions are completely done. While the finishing materials that dry by solvent evaporation also need time to let their solvent evaporate and release from the layer. The finishing layer will only meet his full strength when he is completely dry. Since that, you need to make sure that the finishing layer is completely dry before the product is used or packed. In a finishing process with many steps, you need to ensure that every layer in each step of the finishing process has dried enough before continuing with the next step. Every type of finishing material has different characteristics and may require different drying times that need to be followed. You can find the drying time in the product specifications. It is usually available in the product data sheet of the product.

• Avoid too thick layer of finishing material.

A thick layer of finishing materials tends to take longer to dry. The thick layer will make the process of thinner evaporation more difficult. Since that, the too-thick application should be avoided. One coat or two coats of the coating are more recommended instead of many layers in one application. If you need to build a thick film, then you can recoat the finish layer after it is dry enough. It is a safer process since the drying process will easily occur.

• The condition of the finishing room.

The drying process of a finishing layer is highly influenced by environmental factors, especially the air temperature, humidity, and circulation. In general, the drying process can be faster in a room with a higher temperature and low humidity. The water-based materials are sensitive to the air condition; when the air is humid and saturated with water, the drying process will be very slow and even stop. The solvent-based finishing materials may be less sensitive to the humidity, but they still cannot perform well. You need to consider the temperature and humidity of the finishing room. When the room is humid and cold, it means that you have to provide longer drying time for the finishing process. You may consider installing the oven in the drying room to better control the humidity and the temperature of the room. 

• Use the finishing material type in accordance with the product need.

There are many various types of finishing materials available, each of which has its own character and properties. You have to make sure that you use the proper finishing material according to the product need. The NC finishing materials, shellac, or varnish, are usually relatively soft and not strong enough to withstand the high heat and pressure. Therefore, for products that require a higher resistance, it should be finished with the stronger finish material. The PU or AC clear coat is a stronger material that can withstand higher pressures and temperatures than the NC material.

Do some tests and experiments to ensure that the strength of the finish layer used fulfills the specifications required by the finished products.

Make sure that you use good-quality finishing materials.

The quality of the finishing layer is also determined by the quality of the finishing materials used. It is always better to use good-quality finishing materials, although it is rather difficult to know the quality material by observing it in the wet condition. There are things you can do to minimize the problem of material quality:

• Always check the expiration dates of the materials before you use them.

Make sure the material is not over its expiration date. Avoid too-old material unless you have enough knowledge about the physical properties of the material. 

• Check the physically looked of the material. 

Avoid using materials that are already physically changed since they are usually also already chemically changed.

• Do a proper mixing.

If you want to add some thinner, make sure that you use the proper thinner that is suitable with the finishing materials. The thinner from the same supplier with the type that is recommended by the supplier is the best choice. If you use the catalyzed coating, then make sure it's mixed in the correct formulation according to the product data sheet.  The finishing materials that have good quality will become bad quality if they are inappropriately mixed.

If you have to use the material that is doubtful, then try first it in the small panel. Do check and examine the result; make sure the coating is good before applying it to the stuff. 

• Be aware with the pot life

The catalyzed finishing material, such as melamine, PU, PE, or the other 2 component materials, has a pot life. It is the time from mixing the two materials to the point at which the mixed paint is no longer usable. When the mixed material has reached its pot life, it's already poor and won't give a good finishing layer. Make sure you don't apply the material mix that has already passed its pot life.