tapcon screws – size of drill bit and question about length
pulper_11
| Posted in General Discussion on
Hello – I am going to be attaching my mailbox to the front of my new brick house (the previous owner took the mailbox with him). I will be drilling through the mortar, and not the brick.
I’ve read that tapcons work well for this, and I actually have some. However, I do not have the bit that came with it (seems I’ve lost it).
My first question is:
Can anyone tell me the size of the bit that I should be using for these? The tapcons are 3/16×2 1/4.
As you can probably tell, I’m new at diy but I’m trying to learn.
The instructions also indicate that I should choose a screw length that will penetrate masonry to depth of 1-1/4″. Also, it says to drill hole through material into masonry and that the hole must be at least 1/4″ deeper than installed screw.
These are 2″ tapcons. Although there is just a couple holes to do, this to me seems like drilling pretty long holes in the mortar. If I’m reading the instructions correctly, I will be drilling 2-1/4″ holes in the mortar. I’m using masonry bits, but I’m thinking that it might make more sense to get 1-1/4″ tapcons. Do you agree?
Thanks!
Replies
If you're attaching sheet metal (or something else thin) and are using 2" Tapcons, then yes, you need 2-1/4" deep holes. But keep in mind that the manufacturer recommends a max embedded length of 1-3/4" and likely the mortar it less than 2" thick. Tapcons come in 1-1/4", 1-3/4", 2-3/4", and 3-3/4" lengths, according to the manufacturer.
For 3/16" screws you use a 5/32" bit, and for 1/4" screws you use a 3/16" bit.
Thanks Dan for your reply. Are you saying you would go with shorter screws? The mail box, if i remember correctly, isn't too thick. Therefore, if the mortar is typically less than 2" thick, then would it make sense to go with the 1-1/4" length screw? Then I would do a hole of 1-1/2" for these.
Let me know if I"m reading your post correctly. Thank you for your quick reply.
pulper
Morter bonds brick together. As far as holding tapcons, you might have luck.
Do not overdrive the screw into the morter. If using a power driver, set the clutch so it stops when tight-not when REAL tight.
Blow out or suck out the hole of dust (or run drill in/out/in/out a couple times so the bit pulls out the dust.
I've had good luck using plastic anchors to hold tin mailboxes in morter joints. But use what you have or like.
You can get by with a regular drill. But it will take a heck of a long time to drill the holes.
I don't buy the idea that holes only need to be 1/4" deeper than tapcons. I've had too many sieze up and twist off. So in this case I'd go all the way through the mortar. Can't be all that deep.
If the mortar is old, it may be soft and crumbly. If that's the case you may have to drill into the brick.
pulper
In the morter and in soft brick-no need for a hammer drill but it will take longer-how long? beats me.
The long joints in morter will be deeper, the end joints probably shallower. With two holes in a horizontal straight line-you'll probably be going into the horizontal bed joints.
If the box is tin and the joints struck (finished a bit short of the brick surface I'd use a screw 1-3/4 or 2-1/4 because that's what I carry in my van. With a plastic anchor I'd probably go no more than and inch and a half. The bit for the plastic anchor I would use would be 5/16" and I'd use the anchor sized for a number 10 screw-certainly way big enough to mount most metal boxes.
Here's an aside.
Boycott shipping with FedEx. In the end of August they backed into my mailbox on a pole. Bent up the box, missed the pole.
Yesterday I got a check for 20.09, the cost of the box and 3 numbers. They ignored the bill I sent for 20 bucks for going to get the new box, removing the old and installing the new. This after countless emails and many minutes on the phone with "customer service" (I tend to dwell on the simple stuff-the six weeks of them giving me the usual-we're sorry for the inconvenience............just rubbed me the wrong way). So, I'd like to send them a message-Ship with anyone else but FedEx, the big company that has no concern for one stink'n human being.
Drill the brick
Not the mortar. Much better holding capacity. Be sure to drill 1/4 - 1/2" deeper than the screw length to allow for the chip created when the screw is run into the hole, else the screw may snap off when it bottoms. Also, use a drill or driver rather than screw in by hand.
Good luck.