Welcome back, last month I covered the normal interior fillers, this month I am going to cover two of the slightly more specialised fillers that are available.
Two Pack filler
This is more of a specialised filler, which you would not normally use for general making good to walls and woodwork, but is great for really deep repairs to wood. It is readily available from decorating and builders merchants, but can sometimes be found in the DIY stores.
Two makes come to mind, Cuprinol and Ronseal, the former is a buff colour and the later is white. This type of filler comes in a tin with a stepped lid, only half full with filler, in the top of the lid is the hardener in a small plastic tube, which needs to be mixed with the filler to make it set.
Only mix the amount you need to use, as once mixed you only have about TWO minutes of working time before it will set hard. Never add old filler or uncleaned tools back to the tin or it will set the whole tin off. The advantages of this product is you can fill really deep holes like old mortise lock holes in frames in one go and it will be set hard ready for sanding in THIRTY minutes. If filling over bare metal there is no need to spot prime (this is not a water based filler).
The advantages are
It will take a wood stain and not show underneath, so is great for making good to woodwork that needs staining. Can be used inside and out. A very hard filler so again, will need to be rubbed down with Aluminium Oxide paper.
The disadvantages are
Not flexible, very expensive, sold in a big tin but with only a small amount of filler actually in it.
Fine surface filler
This is an ultra fine white ready mixed filler, which has a very smooth toothpaste like consistency. It comes in a small plastic tub ready to use straight away. These days this is a water based product but when I first started working, it was an oil based filler that could only be rubbed down with wet and dry paper, and I am not sure if this particular product is still available.
The water based one is readily available from all decorating and builders merchants and is a very good product. As this filler is made with ultra fine particles and has excellent adhesion it is used for filling fine surface imperfections on most surfaces i.e. dents, knocks and bruises to surfaces that are too small for other fillers to fill, they would just fall out of because of the small surface area. Great for filling the tiny holes that are left after carpenters fix MDF panels with nail guns.
Relatively easy to rub down with fine grade Aluminium Oxide paper to achieve a super smooth surface, glass like in fact! The oil based one would even fill up the brush strokes grain left on paintwork. Only ever used these days by us professionals who do not like to see imperfections. Can be used inside and out.