Commons problems when using sealants and preventing them
PRIMER OR NOT PRIMER
Some materials always require a primer, others never, and others depend on the surfaces they will work on.
A big problem in the industry is that when they do not know if it should be used first or not, they choose to use it, "just in case the flies", when it's really not always effective, since not all primers work. All sealants and substrates, instead of aiding adhesion, can cause joint failure.
To avoid these cases, make a mock-up test before you start the work and make sure to test all the substrate materials involved, as you will not know what can happen next.
Most soils move. The joints move too. In case of contraction or excessive expansion, this may be due to extreme weather conditions or poor seal design.
To avoid this, it must be treated during the design phase, ensuring that the joints are spaced optimally to allow a high degree of movement.
If you don’t have too much sealant on the top of the backing, there will not be enough adhesive to handle the joint movement. Without the support rod, there’ll be too much material in the joint to stretch properly. If the seal moves and the sealant is too deep or shallow, the sealant breaks.
LOSS OF PROPERTY: BUBBLES
In some support materials, such as closed-cell backup rods, gas can flow for hours after the application of the sealant and, although the bubbles do not disappear immediately, they eventually exit. And this problem can also arise when self leveling sealers are used in wet conditions. Many sealants create a gas and the sealer heals up and down.
When the upper part is skinned and the base is too deep, all the sealant that is trying to heal starts to come out, although this is not a problem for polysulphide-based spa sealers such as Polifix K-10 SL.
To avoid this, do not puncture the backing material and do not install too much sealant into the joint.
LOSS OF PROPERTY: DOESN´T CURE
In multicomponent sealants, the activator and a color pack must be mixed with the sealant. If you introduce unmixed product into the gun, most gaskets will heal properly. However, sealing patches will never heal because of a bad mix.
The main problem with this is that it is difficult to know when the sealant is properly mixed. For this, we recommend using a color pack and mixing the sealant in a clean bucket. First, add the activator, then the color pack. In this way, when you see that the color mixes evenly throughout the cube, the activator will be evenly mixed and you will not get unconscious healing.
LOSS OF PROPERTY: THE SEALANT REMAINS SOFT
This problem arises when the water repellent is applied too early. It may not stop healing, but it will get worse and the sealant will not work properly.
The solution we propose is to spray the hydrophobe on the surface and then reinstall the sealant the next day. In this way, the repellent will act as it should and will not harm the sealer.
LOSS OF PROPERTY: DISCOLORATION
In the event that the sealant does not cure with the specified color, or that some parts get stained, it is often caused by the use of wet tools. Therefore the practice of using alcohol or soapy water when molding the joint to facilitate the work and give the board a smooth and attractive finish.