If the previous coating was a turps-based polyurethane, a two-pack polyurethane will react like a paint stripper on the single pack, due to the solvents being a lot stronger. If the previous coating was also a two pack, it is still recommended that the coating be completely removed so that adhesion between the two coatings does not become a problem. If the coating is not going to be completely sanded off, thorough sanding of the surface to a dull matt finish is required to ensure adequate adhesion.
Using a stain directly onto the timber is not generally recommended for two reasons. Firstly, it is very hard to achieve an even finish on such a large flat area. Secondly, if the floor coating wears through and into the colour, it is almost impossible to touch up the stain without having to sand completely back to raw timber. To avoid these problems, it is best to add a small amount of dye/spirit-based stain into the first one or two coats of a solvent based clear. Always finish off with a clear coat so that when the floor wears or gets scratched, you are only affecting the clear coating.
Generally, a two-pack polyurethane eg Norglass Northane Clear Gloss, or a single pack moisture curing polyurethane gives the best overall protection. Haymes Easy Floor Gloss is also an excellent product to use.
Most paint companies will make their timber finishes with a slight pigment. We call this "natural". We do not usually recommend a clear because it offers the least protection from the sun. The natural colour of the oil (usually a honey or browny yellow colour) will enhance your timber's natural colours and give it longer protection. If you would like a clear, then we could recommend Cutek. Please come into our store to see the timber display area. This will show you how these kinds of wood stains and oils appear
NO. We would recommend a wood cleaner first. This will lift dirt, mould and any buildup of grime out of the grain of the timber. We sell a few brands and we would recommend the most suitable one for your project. Call to discuss.
If you oil or stain over grey timber you will only enhance the uneven dirty colour of the grime and will make it impossible to remove- unless sanded back. You may also need a deck sealer remover and hence you have just made your job tedious and messier!
The majority of time, this problem occurs because the customer has not stirred the product sufficiently. Satin polyurethane's are basically a gloss polyurethane with a flattening base added. This flattening base has a tendency to settle to the bottom of the can, so if the customer does not stir the product, they are using only the gloss polyurethane portion from the top surface of the can. Every product must be stirred with a wide flat stirrer such as a ruler, before and during use.
The reason this happens is that the first coat has not dried thoroughly and the wet solvents in the second coat attack the moist solvents in the first coat. The first coat may not be dry for several reasons such as temperature, film build is too thick, moisture or naturally occurring resins in the timber.
That's ok! Please feel free to give us a call about your problem or question. Or call in with some photos of what you need coat. We can show you some finish coats in store and recommend what preparation steps to take so that you get the best results the first time!