How 2 Plaster .Com
How To Install Plasterboard
There are 3 types of plaster you would need to mix to do a job. BASE COAT, CORNICE ADHESIVE AND BACK BLOCKING CEMENT. All three have different characteristics you should be aware of.
Base Coat is used to tape joints and 2nd coats. When taping in you will be able to use more mix than when applying the 2nd coat.
The setting time for base coat varies from 45 minutes to 60 minutes depending on the brand being used. Mostly inexperienced operators will need a longer setting time, a small amount of citric acid, (1/2 tea spoon) to a mix will extend the working time by up to 20 minutes.
Do not use to much citric acid. If you are working in a hot environment DO NOT USE CITRIC ACID.
Cornice adhesive, while mainly used for installing cornice, has other uses such as, back blocking, taping joins or sticking sheets to masonry surfaces.
When mixing cornice adhesive, the rule, more you mix quicker the set, becomes far more enhanced. Cornice adhesive can be manipulated for a variety or uses. By taking a small amount from the mixing dish and adding powder, rapidly mixing on a board, you can make this set in a few minutes.
As cornice adhesive sets it can be "worked back", by adding small amounts of water. Small quantities of cornice adhesive can be made workable again, for a very short period. This is handy for finishing touch ups to miters in cornice.
Back Blocking Cement
Specially formulated, back blocking cement is a longer setting plaster. Mix with a wet consistency to help with adhesion. Other plasters can be used for back blocking, just use citric acid to increase the working time.