What is the likely cause? How can I avoid the issue in the future? It can happen due to one or a combination of the following: high suction thin coats high temperatures insufficient pressure on trowel in later stages. If the plaster is tending to dry quickly for whatever reason then it is really important to 'push' the plaster in really firmly as it loses moisture and volume. Builderboi Well-Known Member. Sounds like a suction issue and sun drying the plaster too quick, did the plasterers prime the substrate?
Yes they told me they pva'd it. The patches that have crazed went off very quick - prob in hours. My feeling was hot day coupled with high suction background. Any thoughts on what I should do - does crazing get worse with time? Scrim and reskim some guys on here have used large sheets if mesh like scrim on here but I'm sure some one will advise in due course in here.. Thanks very much for your advice! Tell the plasterer you're going to give it an extra coat of paint after the mist coat and charge him for the paint and if it doesn't cover the cracks he will have to reskim it It might cover them it might not they shouldn't get any worse.
The first coat of paint will tell you , it maybe fine,tiny crazing once painted may vanish or the worse case possibly a re skim with embedded mesh, if a re skim get it pva,d properly, get a good grit pva,. Jace Well-Known Member. Some great advice thanks very much. On inspecting tonight I found that some of the crazing areas have blown. Have asked for all blown areas to be removed and then reskimmed. Might suggest fibres on reskim too. Usually in a hexagonal pattern, which typically measures between 5 and 75mm across each hexagon.
Craze cracks are usually very fine and shallow. They do not extend through the whole depth of the plaster. Cracks are usually the result of over-trowelling a rich mix one with a high cement content. Or using sand containing an excessive amount of dust.
Crazing often occurs within a few hours of the plaster being applied to the wall. Cracks may hardly be visible until dust or moisture covers it.
The good news is that craze cracks are of relatively little importance. It can be covered using reasonable quality paint. If necessary, glass fibre tissue can be applied. Use a drywall knife or other scraping tool to gently scrape away any peeling or soft sections of plaster until all that is left is smooth, solid wall. When you've removed all the peeling areas, apply a plaster bonder to the wall. As the bonder dries, it hardens, providing a solid surface to plaster over. Crazing translates to fine cracks in the glaze or surface layer of porcelain wares.
The presence of crazing usually diminishes the value of objects but it can depend on the severity of the damage and rarity of the crazed piece. Crazing is a term used to reference fine cracks that can be found in the glaze of pottery or china.
Crazing can be present in varying degrees. Sometimes items may have a couple of crazing lines on one side and not the other, other times the crazing can look like a spider web and cover the entire item. Cracks in any dishes hold bacteria so they are always unsafe. Never use dishes with any cracks in them for food.
If dishes have any cracks, even tiny crazing , you should think of them as unsafe for foods and eating, any kind of foods, even dry foods. And what is unsafe for humans is also unsafe for your pets. Crazing is a glaze defect of glazed pottery. Characterised as a spider web pattern of cracks penetrating the glaze , it is caused by tensile stresses greater than the glaze is able to withstand. Crazing happens when the top layer of the acrylic pour painting dries faster than the underlying layer which is still wet.
When this happens the top layer of the acrylic film will form a skin as it hardens and continues to stretch, and if it hardens too fast it will break. Types Clay plaster. Gypsum plaster. Lime plaster. Cement plaster. Heat resistant plaster.
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