Force it through, using a puddler and puddle box. Add lime putty to sand, by squeezing it through a 29 - 32 mesh screen, without the addition of water. If it is loose in any place remove the plaster and replaster it with mortar left from the scratch-coat.ġ/2" thick, made up of skim coat followed by brown-coat, wet into wet, using same mortar for both coats Second coat: Identical to the coat described above, following the directions explicitly.Ĭhecking:Check this coat thoroughly by carefully tapping the surface to see that it makes a good binding. It must be done carefully so as not to loosen the mortar. Level the coat by rubbing it off and building it up, with the straightedge, darbe, and water level. Throw mortar vigorously so that it spatters - throwing with force avoids air bubbles which may burst.
Throw so that the mortar is squeezed tight against the wall. Throw mortar from a small box that can be moved along side as one advances with the work. New boards should be placed so as to catch falling mortar, so that it can be picked up and re-mixed with the batch. Throw from a short distance from the wall and in a slanting direction, from bottom to top, from left to right, and with a slight twist of the trowel. Throw mortar with a squat broad diamond shaped trowel. Chop mortar again before using, and don't add more water. Wet wall thoroughly first, giving it all it will take with a water hose or sprayer. Water can be added a bit at a time after the first two choppings, but only enough water so that it slips on the trowel and holds its shape in throwing. The remix it several times by chopping it until it becomes uniform in color. Let the mixture, without the addition of water, soak for 2 days. A puddler and puddler box is the best way. Mix the lime putty and the dry mixture without the addition of water, in to a new box (or one that has never been used for anything but straight lime and sand plaster.) Add the lime putty to the dry mixture by squeezing the lime through a 29-32 mesh screen. Or 2 1/2 parts sand 14-16 mesh & 1/3 part crushed tile or pottery waste or unglazed triturated porcelainĭry mix the sand with the crushed tile, potter or porcelain, (If using tile etc, it should be crushed to the size of split peas and sifted through large than 12 mesh screen.)Ĭonsistency: Mortar just threatens to run off a tilted trowel, more, liquid than other coats. The First Coat or the Roughcast or Scratch-coat Layer: 1" thick made up of two identical costs each 1/2" thick In the following section, the specific details are given for each layer of plaster. For more southerly locations, the day would be 12 to 16 hours. The frescoes I painted were done at northern latitudes (northern Oregon and Minnesota) and I found that my working day lasted from 18 to 22 hours with this method. I discovered that if I extended the area set for a day’s work about seven inches beyond the area that I planned to paint in one work session, that I could extend the length of the painting session several hours beyond the time which would be allowed if I had plastered only the area to be painted. The first three are laid all at once the final layer, the intonaco, is laid piecemeal as the work progresses. This is best done with a fire hose.įour coats of thin plaster are applied for the ground of the fresco. So it is very important that after the time has been spent preparing the lime and sand correctly, the wall must be wet thoroughly to allow the adhesion of the lime plaster. If the wall is not wet enough, there is the possibility that the lime-water will absorb into wall instead of working its way outward. The wall must give water to the fresh plaster coat and not swallow it up. Poorly wet walls will cause the mortar to come off or remain soft. While dryness was a priority as a normal condition for the base wall for a fresco, the wall must be very wet when beginning to apply the plaster into which the fresco will be painted. It should have aged a year or two before being used. The lime plaster must also be without extra water, which again would prohibit the carbonization process. Wet grains of sand prohibit the lime from carbonizing and adhering to the surface of the wall and to other grains of sand. It is the only way to maintain control over the final outcome of your work. Knowledge of the plastering techniques and recipes is an absolute necessity for the fresco artist. While I often hired a plasterer, before I did this, I researched the process thoroughly and learned to do it myself. The success and longevity of fresco painting depends largely upon how the mortar is prepared and applied.
0 kommentar(er)
