You may have seen professional builders and decorators using gun applicators
. This is a very useful tool that will also benefit those undertaking DIY jobs as well. Foam gun applicators can take a bit of practice to get the hang of but they do provide a much quicker and easier way for you to apply products such as sealants, mastics and expanding foam.
Preparing the Nozzle
Products for use in gun applicators will come in basic tube designs with long plastic nozzles. You will need to cut this nozzle before you can use the product and it is important to get this right as it will affect how the product is ejected from the tube. Ideally you should cut the nozzle at a 45 degree angle as this will make it easier for you to apply the product against a flat surface. The plastic nozzle is tapered so if you cut towards the tip you will be able to apply a very neat, thin line of the product. If you cut much closer to the butt of the nozzle then you will be able to apply a larger line which is suitable for bigger areas. Once you have cut the nozzle to the required length then you can screw it onto the tube and then insert it into the gun applicator.
Getting Started
Once you have the gun ready to use prepare the area you will be applying the product too. Mastics, sealants and expanding foam will not stick easily to damp, dirty or oily surfaces so it is important to clean these areas first before you apply these products. When you are ready to use the gun squeeze the trigger slightly until the product is just at the tip of the nozzle. Now place the nozzle on the area to be covered and squeeze gently until a controlled line of the product is forced out of the nozzle. Keep a firm, even pressure on the trigger and if you are sealing a crack or gap then move the gun at the same time as pulling the trigger to form a smooth, even line. Try not to move too quickly otherwise you will not apply enough of the product. Also avoid moving too slowly as you could apply too much which can be difficult to clean away afterwards.
Creating a Neat Finish
If you are using a gun applicator to apply a line of sealant to an area then you can finish this off neatly by dipping your finger in some washing up liquid and then just skimming it along the line (don't press too hard otherwise you will displace the sealant). This will tidy up the sealant and the washing up liquid will prevent it from sticking to your finger in the process.