The oldest traces of plaster renders are 9,000 years old ! We also know that 5,000 years ago, the Egyptians burnt gypsum in open-air fires, then crushed it into powder, and finally mixed this powder with water to make jointing material for the blocks of their monuments, such as the magnificent Cheops Pyramid for example. The ancient Egyptians used models of plaster taken directly from the human body.
The Greeks also used gypsum, in particular as windows for their temples when it was of a transparent quality ("selenite gypsum") and the Romans cast in plaster many thousands of copies of Greek statues.Of course, materials and techniques have moved on since those days and we now have potentially, a much easier time of it by the relatively straightforward application of a range of ready-mixes to flat plasterboard, in most cases.
However, the technique of laying up correct ly mixed and perfectly flat, glass-like finishes is still dependent on good, solid skills training, patience and understanding the materials you work with.It's quite an easy mistake to make, for example, to lay plaster onto the surface very thinly, by scraping on with the trowel, instead of laying onto the surface. The plaster then dries off too quickly, not adhering sufficiently to the surface, and there will not be enough plaster depth onto the surface in the first place for trowelling up later.
Applying plaster should be as reasonably even as possible so once the whole wall/ceiling is plastered, you can start to trowel out some of the ridges later on. However, resist overly reworking by adding clumps of plaster or playing with it too much, once having just applied onto a surface, but instead, lay on a band of plaster and smooth out your strokes so that you have a reasonably level application the first time, then move onto the next section of your surface to be plastered until completion.
By applying a few strokes of plaster, it is sometimes tempting to work on that particular area trying to level out as much as possible before moving towards the next strokes, but by paying too much attention to the area you have just laid on, you are helping to dry it off more quickly plus you are likely to interfere with good adhesion to the wall surface. So in summary, lay on, smooth level strokes and move on until completion.
Finding out all the time-honoured and well-tested secrets of the trade is invaluable training, and will save time, money and frustration by being shown and taught the kind of mistakes you should avoid and the correct ways to go about achieving practical success.
AbleSkills offers a range of courses for those of you who wish to upgrade your DIY skills to simply decorate your home and full-time block course accredited NVQ training for those looking to begin their training for a career in the Construction trades industry. There are also great opportunities to see what you can do on weekend courses, so there's bound to be a course time for you to to get started!