At my wits end here!
I'm trying to install some shelving in a closet. Most of the walls in my house are plaster over concrete brick or plaster over concrete block. One wall in this closet has several layers of strange stuff (I'm guessing drywall and plaster) with no hollow areas that would allow a normal molly bolt to expand. Therefore, I've had to buy 1/4" x 3-3/4" Tapcon concrete screws that will hopefully reach the concrete block or concrete brick that I believe to be behind the layers of strangeness.
Naturally, I had to buy a corresponding drill bit. Got the Tapcon branded SDS drill bit size 3/16" x 7" and was excited to finally get this project finished.
Tightened the drill bit into my Makita drill (it is a one-speed but has a hammer drill option) and gave it a whirl only to find that there's a huge wobble at the tip of the drill bit! I can't remember any of our other drill bits ever having this issue. I noticed that the drill has 3 prongs that hold the drill bit (is that called the chuck??), but the drill bit itself is constructed with 4 "sides", and I'm wondering if this discrepancy is causing the issue.
My husband thinks it doesn't matter, and we should just go ahead and use it as is ... but isn't this wobble going to make the hole too big for the screws to then work properly??
Do I go ahead and use the bit anyway, or try to take it back to the store and get a straighter one, or maybe a different brand (though I don't recall seeing other 7" bits in the display)?