There are numerous types of caulk, including silicon, acrylic, latex, rubber and oil-based, and the easiest way of applying is to use a caulking gun. A caulking gun is a metal device into which fits a tube of caulk. Once properly loaded and with the tube prepared, the caulk is forced out of the tube’s nozzle in an even bead. Properly loading a caulking gun involves several steps. It is, however, something you will have to learn in order to effectively apply caulk as a sealant both indoors and outdoors.
A caulking gun is basically a hollow metal cylinder, open on the top with a handle and trigger attached to the bottom end. The two ends of the cylinder are enclosed circles with holes in them. Through the front end goes the caulk tube’s nozzle. Through the back end there is a straight metal rod slightly curved at the end. On the inside of the cylinder this rod is attached to a circular disc. This rod and disc combination is controlled by the trigger.
Preparing the Tube of Caulk
Before you load the caulking gun, first prepare the tube of caulk. The tube is relatively narrow with a plastic nozzle or spout at the front end. The back end of the tube is not the same material as the tube’s body. Rather, it is sealed with a movable plastic disc. Depending on the size of the bead you want to squeeze out of the nozzle, take a utility knife and cut the tip off of it. The size of the hole you cut should be between 1/8 and ¼ inch in diameter. Cut the tip off at an angle. This allows the nozzle to remain flush with the surface you are caulking as you hold the gun.
Loading the Caulking Gun
With the tube prepped, you can now load the caulking gun. Hold the handle of the gun while simultaneously pulling back on the rod protruding from the back end. Older caulking guns may require you to rotate the rod 90° before it will pull back. With newer guns it simply slides back. Place the tube of caulk into the open chamber of the gun with the nozzle to the front. Slide the nozzle through the open front end of the gun and move it as far forward as it will go. Now hold the trigger down and manually push the circular disc attached to the front of the rod right up to the back end of the tube. The metal disc will fit right into the back of it, pressing up against the movable plastic disc.
Test the Caulking Gun
With the rod firmly against the back end of the tube, when you squeeze the trigger, you will feel resistance from the tube. The pressure, however, forces caulk out from the tip of the nozzle. Test it to make sure the there is resistance there. Now you are ready to apply the caulk.
A common problem with older caulking guns is that there continues to be pressure on the back on the tube even when you set the gun down. It leads to caulk dripping out of the tube and being wasted. New dripless caulking guns are available that eliminate this problem. When the trigger is not engaged, the rod applies no pressure, and you end up saving a lot of caulk.
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