Let me ask you a question: When you say it’s having trouble getting started, do you mean by simply twisting with your Thumb & Finger? If so, it’s because twisting just that tiny 6-48 Tap with your fingers does not generate enough rotational Torque to cut through & push the old material. However, that can be easily remedied with a little homemade Torque Multiplier. I made mine with a 1/8” Drill Stop. (I drilled mine out with #25 Cobalt drill bit because I have them, but the 1/8” works just fine by spreading it open slightly more with a flat blade screwdriver.) Now, my 6-48 Tap measures .136” on the round Shank. (Not the square drive portion). This gives ample amount of torque without being enough to strip the threads. Works perfectly. And, you’ll likely have better luck finding a cheap 1/8” drill stop over a 6-48 Chaser tool! And I guarantee it will be cheaper! I purchased a set og these drill stops fit like $6 from Amazon.