Review on 🔧 Koopi BI METAL Plastic Drilling Replacement by Dipp Samrock

I bought this 3" bi-metal hole saw to cut holes in the ceiling and half a dozen TORCHSTAR E-Lite ultra-thin 3" LED downlights install series. . The drill bit is built into the mandrel, but the mandrel must be screwed into the base of the hole saw before use. The threads are tight so you will need a wrench or pliers to tighten them. The axle rotates clockwise as does the hole (right-to-tight) so it will remain fixed as long as you use the clockwise hole saw. If you change direction, which isn't really necessary, although I know some people advise you to start counter-clockwise to make a guide groove before changing direction to make a cut, the shaft may shift loosen and turning counterclockwise long enough under load may throw the blade off the shaft. Because most jigs have a decorative panel that hides any cracks in the drywall caused by the saw, there's no reason to run the disc backwards and risk injury. After making a few holes, I noticed that the drill bit dangled a bit in the mandrel. There is a set screw on the side of the mandrel that needs to be tightened and a hex tool is included with this hole saw along with an additional approx 1/4" drill bit. I would recommend putting the blade and drill bit in front and in between to check the cuts to make sure everything is tight.I didn't use a quick release spring that just slides over the drill bit so after each cut I had to pry the drywall out of the saw with a flathead screwdriver.This hole saw is inexpensive and does a great job done to cut the 6 holes I needed to install LED recessed lights.