Painting Tips for the DIY Painter
In over 25 years of being a professional painter I've seen many amateur painters do a great job though on a few occasions I've seen paintwork that was so breathtakingly awful I can't help wondering why they even bothered . A terrible paint job is not only unpleasant to look at but would have to devalue the property to some extent.
Anyway on a more positive note , there is no reason you shouldn't be able to do a professional job and make sure your time and money is well spent.
For the time being I will just mention some of the mistakes people make and some common things that cause confusion. I'll also include some links a few more extensive websites that I think are worth looking at.
I've noticed that people often either do no preparation at all or way too much .The key is to have a good look at all the areas you're going to paint and concentrate on the places that really need attention.
- Washing down..... for interior walls,ceilings and woodwork there's is often no need to wash every surface. Instead, concentrate on areas like kitchens ( where you may have grease on the walls and ceilings) , bathrooms (mould and soap residue on all surfaces), around light switches and other places that are often touched ( grime and hand grease). Sugar soap is probably the best all round cleaning agent .....it's best not to use normal detergents as they can leave a residue.Bleach or other products which contain sodium hypochlorite are effective for mould though they should be used carefully.
....for exterior surfaces its a good idea to always give them a wash down. As well as just being dirty they may also have mould and /or be chalky ( from sunlight breaking down the old paint).Often the best way of cleaning down outside is with a hose , a bucket with a bit of sugar soap and a broom for scrubbing. Be wary if you use a waterblaster ,they can do a lot of damage if you're not very careful.
Again , sanding is something people either do too much of or too little of . There are two main reasons for sanding things down : to improve adhesion for the next coat
to improve the quality of the finish.
-Walls and ceilings .... these days nearly all walls and ceilings both inside and outside would be some sort of acrylic /latex (water based ) paint . This means they shouldn't need any sanding for adhesion purposes. However it is worth having a look over all the surfaces for any imperfections. If you aren't happy with the way they look then you should definitely give them a rub down to remove any lumps and bumps.
For new work such as plasterboard or timber it is often better to sand after the first coat of primer or sealer . It is then easier to see what needs attention and it is often easier to sand to a smooth finish . You can then sand between further coats if necessary....let your eyes and hands decide if its needed.
For cement rendered walls it is best to rub them down with a brick or something similar before painting..this will remove any loose sand and other imperfections.
-Doors,Windows& Woodwork......these are often coated in enamel(oil -based) paint . I'll tell you how to check here.If they are enamel it is usually a good idea to give them a light sand ,especially if they are high gloss. It is a good rule to always use an oil based undercoat on enamel surfaces to ensure good adhesion whether your putting an oil or a water based paint over the top.
-Sandpaper and techniques....... the main thing to know about sandpaper is the grit size.This is just the coarseness of the paper and is represented by the number on the back ...the smaller the number the coarser the paper. I generally only keep 2 or 3 types of paper on hand...some 120 grit white paper which is good for most things ....some 60 grit yellow paper which is good if you really need to hard sand a rough surface like flaking weatherboards.....and some 180 grit white paper which is good for fine sanding or sanding between coats. I would suggest buying some of each (you can get it by the metre ) and then just using your commonsense...if it seems to be cutting up the surface to much use a finer one and if it doesn't seem to be doing anything use a coarser one. For timber always sand along the grain and not across it.
If you want to use an electric sander ,either an orbital or a random orbit sander are good options for smoother areas like interior walls and doors . For harder sanding such as flaking timber exterior there are special sanders you can buy or hire . I wouldn't recommend using a normal disc grinder with a sanding pad...these spin much too quickly (10000 rpm) and you can easily do a lot of damage to timber . Either use a slower specialised sander or a random orbit type.
Patching and Fillers
The main thing is obviously to use the right filler for the job . For finer filling inside any of the plaster fillers are fine as are the newer synthetic fillers . These are usually easy to sand though if filling deep holes both are slow to dry .If you are filling deep holes or holes in doors for example it may be an idea to get some 2 part filler ( plastibond ,builders bog etc) . Because these dry through a chemical reaction they set very quickly and very hard..perfect for deep holes or if you're in a hurry.
If you have big holes knocked in walls or ceilings it is usually best to try to fix something across the back of the hole like a piece of fibro or timber screwed through the edge of the hole to hold it in place . You can then use a plaster filler ( cornice adhesive is good ) to patch the hole..though this usually takes a long time to fully dry. Personally ,I always use a 2 part filler first and then finish over the top with a plaster filler.
For exterior filling make sure the filler you buy is marked for exterior use and remember you can also always use 2 part filler outside. Linseed oil putty is fine for any tiny holes like nail holes though you should let it skin over a little before painting.
The main thing trick to using fillers is to have good clean filler blades and to overfill but not too much. People often just slather on huge amounts of filler and then find it takes forever to sand it back ...especially some of the harder compounds. It is well worth making the effort to just overfill the hole in a neat and smooth way...it may be worth doing several finer fills instead of trying to do one thick one. If you are having trouble sanding your patches try using a much coarser sandpaper first and then finishing the last little bit with a finer paper.
Before you Paint
It never ceases to amaze me how careless some people (including professional painters) are about covering floors and furnishings before painting. Believe me it is not worth the risk of not covering everything properly...any time spent is well worth it in terms of speeding up the actual painting ,your confidence to work quickly, the quality of the job and the hassle of cleaning paint of furnishings or carpet...if you can!
After pushing back furniture and removing pictures and so forth from the walls I always use a masking gun to mask around the floor of the entire room ( these are just a little machine that runs masking tape onto a roll of paper 12 inches wide that you can then pull off and stick down in any length).I then lay cloth drop sheets over all the floor area and use cheap plastic dropsheets over all the furniture. The plastic dropsheets are great for covering furniture because they are cheap , light and clean and you can see whats underneath them ...however they aren't so good for floors ,they slip all over the place and the paint spots don't dry on them so you can get wet paint on your shoes. It is probably worth getting a proper dropsheet or some old sheets might do though they tend to be a bit thin. You probably won't want to buy a masking machine but it is still a good idea to run masking tape around the floor...try not to paint onto the tape to much though ,the paint will get under the tape unless its on a smooth surface and you really rub it down firmly.
Which Paint Should I Buy and how much of it?
I guess these are the things people struggle with the most. One of the things you should know when painting over existing paint is whether it is enamel (oil based) or acrylic (water-based). You may be able to get an idea just by looking at it.....enamel (especially gloss enamel) tends to be very shiny, hard and often looks smoother than water-based paint.Mind you there are lower gloss enamels and some of the gloss acrylics can look quite similar to enamel. The best way is to test the surface by rubbing it with methylated spirits....if the coating seems to be dissolving then it is sure to be acrylic (water-based). If it doesn't seem to affect it then you're painting over enamel.
The main reason it is important to know this is because there can be adhesion problems when painting over enamel ..ESPECIALLY high gloss enamel.If ever you come across new paint easily peeling off the old paint you can be nearly sure it will be because acrylic has been painted over enamel.
There are a couple of ways to deal with this ....the most sure fire way of painting acrylic over an enamel is to make sure it is clean, then give it a light sand and then use an oil-based under coat before you apply the acrylic top coats. In reality if the surface is clean and you use oil-based undercoat you really shouldn't have to sand it back first.....oil-based undercoat is a great product and if ever in doubt you should use it ,it sticks to almost anything and gives you a good base to paint over.
Another way is to use an acrylic undercoat...these have really improved in the last few years and if you buy a good quality one it will be almost as good as oil-based undercoat.
A third option ,if you have the energy ,is to totally sand the enamel back to a smooth ,dull finish ....any type of paint should adhere to that.
-Should I use Enamel or Acrylic.....for quite a long time now the standard system was to use enamel on all doors,windows and woodwork and to use acrylic on walls and ceilings. This still applies today and is my preferred paint system....enamel is very hard wearing and very washable and is perfect for anything that really gets hard traffic. The modern gloss acrylics or (acrylic enamels) are getting better all the time however I don't believe they are as good as real enamel at this stage. The main reason people are going with acrylics on their woodwork is because it is easier to use. This is true to an extent...you can wash acrylic paint out of brushes and rollers with water instead of turpentine for enamel...the acrylic usually dries in a few hours instead of overnight for enamel ....the acrylic tends to have less smell than enamel ... the acrylic is also somewhat easier to use ..ie it goes on easier and is less likely to run than enamel. I guess it's up to you.
One more point...should you ever use enamel on walls or ceilings . Well, about the only place you might see enamel on walls these days is in a public toilet...so if you have any areas that really get a hiding and you think you'll need to be scrubbing the walls all the time then think about enamel ..otherwise stick to acrylic on walls and ceilings.
Putting on the Paint....I can't stress enough the importance of buying a decent brush. As an experienced painter ,even I struggle to paint with a cheap brush. You will be amazed at how much easier it is with a quality brush and as a non-painter you need all the help you can get.
Basically you will need a wall brush for large surfaces and a smaller brush ,sometimes called a sash cutter , if you a doing windows or other finer detail work.
A wall brush is generally wider .. often 3 inches (73mm) or even 4 inches(100mm) and thicker . The idea is that the larger amount of bristles will hold more paint and you can cover more ground faster .
A sash cutter is often only 2inches(50 mm) wide or even less and is about half the thickness of a wall brush with tapered bristles.
If you only want to buy one brush then get a 2 inch sash cutter ....you will find it will be easy to use for cutting in walls as well as for finer work . These days any quality brush will tend to be made with synthetic bristles as opposed to the old style natural bristle brush. I think you need to spend at least $20 (aust) to get a decent brush ,compare a few and look for ones that have longer ,finer, tapered bristles ...I'm not sure why but I find that any brush with a purple -ish coloured filament (bristle) seems to give good results
You can also try these sites if you like......
This one has quite a lot of good info....http://www.house-painting-info.com/
and this one has some good articles....