Does a 5/16" screw for wall mounting a tv require a 3/8" masonry bit?

The Coffee Shop
1

Putting my tv up on the wall, which is brick.

The mounting instructions call for a 5/16" screw into the wall (their diagram says NOT to drill into the concrete, but to the brick itself, which I think is wrong). Jerk 23 year old at Home Depot said “Yes, use a 5/16 masonry drill bit.” But upon trying to put the plastic anchor, it would not fit, at all. So, it seems like I need a larger masonry drill bit. Is a 3/8" the right one?

I’ll be ok with using the existing hole (only did one) plus some epoxy to make all the screw/anchors sound, but should I be doing something else?

In case you can’t tell, I think this should be rather simple, and I’m pretty pissed off it has gotten even remotely complicated.

2

Dont drill into the mortar it will crumble. The 3/8 should work. You really just need it to be smaller than the screw and anchor so it will hold. if youre really frusturated, ill take the tv off your hands. :slight_smile: problem solved.

3

I’ve had nearly 15 people tell me TO drill into the mortar, damn.

Instructions said not to, but all people said to do so because I’m more likely to shatter the brick. Thoughts?

The plastic anchor wouldn’t fit the 5/16" drill hole, I’m inclined tomorrow night to try the 3/8". THanks.

4

I’ve had nearly 15 people tell me TO drill into the mortar, damn.

Instructions said not to, but all people said to do so because I’m more likely to shatter the brick. Thoughts?

The plastic anchor wouldn’t fit the 5/16" drill hole, I’m inclined tomorrow night to try the 3/8". THanks.

dont listen to me, I was always told the way I told you. just googled it and everything says mortar. If you use a high speed drill and sharp bit the brick should be fine. unless the anchor expands and cracks it. So go with the mortar I guess, as long as the bracket holes line up between he bricks.

5

Get a hammer drill and chisel out the bricks where you will mount the bracket.

Put Quickcrete into the space where the bricks were and then after it dries, get some "1/2 Tapcon bolts and that fucker won’t move.

Ok, I’m kidding, but that would eliminate the crumbling mortar problem.

6

I’ll ask my girlfriend. She just mounted by plasma onto my brick wall.

She’s handy like that, which is handy.

7

3/8 is the right size for 5/16 hole.

You should be drilling into the brick - you won’t crack it. Mortar has no where near the integrity of fired brick, and eventually a plug will pull out of mortar. I have had to replace way too much on old houses where they put a plug into mortar to attach something.

Chainpin’s tapcon suggestion is overkill, but right in that it will be extremely secure.

8

I would drill into the brick. I live in a loft so I’ve mounted a bunch of stuff to the brick walls. Anything heavier than say a small shelf, I wouldn’t use the mortar. I’ve pulled an anchor out of mortar without too much effort. If you ever plan on drilling into brick again, maybe get a hammer drill. It’s only $20 from Harbor Freight and it will drill through brick and concrete almost as quickly as a regular drill goes through wood. Drilling into brick or cement with a regular drill and masonry bit takes a lot of patience.

9

3/8" masonry bit, I would drill into the brick (although either should work).

10

Do NOT drill into the mortar, drill into the brick and use masonry or concrete anchors.

11

The size of the hole should be on the box the anchors came in. The size of the hole will depend on the type of anchor, make manufacturer etc.

Before I drilled a bunch of 3/8 holes I’d check with the manufacturer or the box.

~Matt

12

I reread the entire directions, and found a small diagram where they label the drill bit as 3/8", thanks for suggesting I review, that was important.

Thanks to all for the advice. I’m attempting to drill into the brick. Hole #1 went fine, hole #2 is taking its sweet time as I have a crappy old drill. I need to rent a hammer drill from Home Depot…

13

I reread the entire directions, and found a small diagram where they label the drill bit as 3/8", thanks for suggesting I review, that was important.

I only suggested it out of some bad experiences. I have had different anchors require different holes with the same screw size. Having had made the mistake of using the same drill size as “The last one I used” and ending up with some holes to fill, thought I’d suggest “Read the box” :slight_smile:

~Matt

14

It was a good suggestion. I had spent an hour previously going over ever single page to figure this out, but couldn’t find the info. I figured it HAD to be in there, thankfully you got me to look again…

Using my 20 year old screw driver to drill these holes is slow going, man.

15

Using my 20 year old screw driver to drill these holes is slow going, man.

Yes, a hammer drill is almost a necessity for masonry. Also make sure you haven’t nuked the carbide on your bit. If that’s chipped, broken or gone…you’ll be getting nowhere fast.

~Matt

16

I’ve definitely left the carbide at the bottom of the hole a time or two. That was…unpleasant.

17

I’ve definitely left the carbide at the bottom of the hole a time or two. That was…unpleasant.

Actually I find getting carbide out if a hole is easier than high speed. Get a chisel and pound away. Carbide is pretty brittle and will often just shatter and you can just blow it out. I’ve nuked a number of drills/mills/taps in steel over the years and most of the time carbide is easier to get out. Taps of course are the worst but you can still do the same thing with carbide and then pick out all the broken teeth out with a tiny pick. HS OTOH won’t shatter, can only be drilled with carbide…which often times breaks off. I think we end up getting HS EDM’d out of block more often than carbide.

Now if the drill breaks off leaving the carbide portion covered with a chunk of HS…that sucks.

~Matt