How To Remove Paint, 3 Different Methods

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There comes a time in every decorator's life when the repainting has to stop, and it's time to strip off and start again. Paint is marvelous stuff, capable of covering a multitude of sins on all sorts of surfaces, but there are situations where it is not possible to redecorate by applying yet another coat over the top of the existing finish. The old finish may be cracked and peeling, or there may already be such a build up of paint on the surface that further layers will lead to problems like jammed windows or obscured detail. When this point is reached, there is no real alternative but to stripping off the finish and starting again with a new paint system applied to a bare surface.


There are three main ways of removing paint (and related finishes such as varnish) from wood and metal surfaces.


The First Method

Is to use some mechanical method, in other words an abrasive treatment that sands away the paint film. Hand sanding is the simplest and by far the hardest method, and is normally reserved for rubbing down of otherwise sound surfaces. Using a power tool speeds up the process, and you have a choice here of using sanding discs, drums and belts, or of resorting to tools such as the flap wheel sander or the paint flail. The flap wheel has tongues of abrasive paper or cloth attached to a central spindle, while the paint flail uses metal spines to literally flay the paint off the surface, and is a fairly drastic method not to be used on fine woodwork. The flap wheel would be a better bet here. In addition, wire brushes may be used to strip paint from metalwork, especially on intricate surfaces where other abrasive treatments cannot reach. Abrasive stripping methods can be used on all types of paint. It's a sensible precaution with any mechanical stripping operation to first check that the paint is not lead based, this can be done with a home lead testing kit purchased from any hardware or paint supply store. If the paint tests positive to lead, then you have two options, 1 is to get the items professional stripped or 2 make sure that you strip the items outside in a well ventilated area and wear safety goggles and a suitable respirator not just a face mask. Remember that sanding lead based paint atomizes it, turning it to very fine particles that then settles over everything. This dust is what is dangerous to you or your family and friends health.


The Second Method

Widely used for stripping solvent-based paints from wood and metal, is heat. This softens the paint film, allowing it to be scraped off in a molten state, and is one of the quickest and cheapest methods available once you have bought the heat source.

The former runs on butane gas in throwaway cartridges (hand held lamps) or on propane from refillable cylinders (hose type blow­torches, more economical for large jobs). A special nozzle is fitted to form a soft, flat flame, but even with this fitted there is a considerable risk that wood will be scorched, so this method is not used where the wood is to be left exposed, but is quite suitable for metal. Heat guns, which resemble powerful hair driers, are safer and easier to use and do not scorch the wood so easily. Care must be taken when using either type near glass, which could be cracked by the heat; some heat guns have a special deflector nozzle for stripping paint from windows. See using hot air guns fact sheet. High heat guns are outlawed in many states as are torches. See speedheater infrared paint remover for low heat now acceptable.


The Third Method


Is to use a chemical stripper. A gel that softens the paint film, rather like heat it like a blowlamp does, so allowing it to be scraped off the surface. Chemical strip­pers are generally based either on methylene dichloride or on sodium or potassium hydroxide (caustic soda or caustic potash), and will strip solvent-based paints and most varnishes (but not emulsion-type paints).


There are also strippers specially formulated for removing varnish, and also for stripping the textured paints widely used on ceilings; this latter type will often also strip ordinary emulsion paints reasonably suc­cessfully. Always wear goggles when using paint strippers above eye level.



When using heat or chemicals, you will need a tool to scrape off the softened paint. This can be an ordinary flat-bladed scraper, or else a special tool called a shave hook that has a blade at right angles to the shaft. The head may be triangular in shape, or may have convex and concave blades as well as a straight one, known as a combination shave hook for stripping mouldings.

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