posted
I'm preparing to install a 4'x4' HDU sign up on a brick wall, about 10' to 12' off the ground. I intend to use a 3' aluminum French cleat at the top. then anchor the bottom with galvanized steel angle. Would 10 "Tapcon" screws at the top, and about 4 at the bottom, hold this thing in the brick/mortar?
Thanks
-------------------- Wayne Webb Webb Signworks Chipley, FL 850.638.9329 wayne@webbsignworks.com Posts: 7403 | From: Chipley,Florida,United States | Registered: Oct 1999
| IP: Logged |
posted
Sure will Wayne. There is not much force pulling the sign away from the wall. Most of the force is a shear force which the tapcons will handle more than the weight of your sign. In fact I would go with 6 on top, maybe 8 at the most.
Mike, why an impact driver? Wouldn't that just crumble the mortar as the screw was being driven? I've always used a cordless driver or socket wrench to just snug up the tapcons without over tightening them. Never had one pull out yet.
-------------------- Dave Sherby "Sandman" SherWood Sign & Graphic Design Crystal Falls, MI 49920 906-875-6201 sherwoodsign@sbcglobal.net Posts: 5397 | From: Crystal Falls, MI USA | Registered: Apr 1999
| IP: Logged |
posted
I must be missing something on my installs because everybody here wants to use more screws than I would...it is a 4'x 4' HDU sign...why so many screws?
posted
over-engineered .........is better then under-engineered))))
-------------------- joe pribish-A SIGN MINT 2811 longleaf Dr. pensacola, fl 32526 850-637-1519 BEWARE THE TRUTH.....YOU MAY NOT LIKE WHAT YOU FIND Posts: 11582 | From: pensacola, fl. usa | Registered: Nov 1998
| IP: Logged |
posted
I use Tapcons all the time. And I second your thought Dave Sherby about the impact - too often mortar mix is not too stable, and / or older soft brick. To my thoughts, the hardend Tapcon threads kind of 'tap' there way into the brick or morter, creating 'threads' and really locking in. With an impact, it's pounding and drilling, with the pounding possibly breaking up the substance you want to lock into via the threads of the Tapcon itself. Just my thoughts.
Mick Samsel
-------------------- Mick Samsel Creative Services Cherokee, IA Posts: 498 | From: Cherokee, Ia USA | Registered: Jan 1999
| IP: Logged |
posted
I use Tapcons all the time. And I second your thought Dave Sherby about the impact - too often mortar mix is not too stable, and / or older soft brick. To my thoughts, the hardend Tapcon threads kind of 'tap' there way into the brick or morter, creating 'threads' and really locking in. With an impact, it's pounding and drilling, with the pounding possibly breaking up the substance you want to lock into via the threads of the Tapcon itself. Just my thoughts.
Mick Samsel
-------------------- Mick Samsel Creative Services Cherokee, IA Posts: 498 | From: Cherokee, Ia USA | Registered: Jan 1999
| IP: Logged |
posted
i think what mischeif was saying was.... to start a tapcon screw an "impact" does a better/easier job..TO START IT.... then i would change the drill back to drill, no impact to finally seat the screw. this is how i have done most tapcons.
-------------------- joe pribish-A SIGN MINT 2811 longleaf Dr. pensacola, fl 32526 850-637-1519 BEWARE THE TRUTH.....YOU MAY NOT LIKE WHAT YOU FIND Posts: 11582 | From: pensacola, fl. usa | Registered: Nov 1998
| IP: Logged |
posted
I think OP is right. Mike was referring to using a hammer drill for the drill bit not the tapcon.
In concrete, a single 1/4 inch tapcon embedded 1 1/2 inch has a shear strength of 1200 lbs and a pull out strength of 1380 lbs. Even in mortar, if you end up with only 20% of the concrete values, you are at 1200 lbs. shear strength and 276 lbs pull out. 4 tapcons on a 40 lb sign is adequate, 8 would be serious over kill. I once installed a 3/4 inch MDO french cleat in a brick wall and took a pry bar to it just to see how strong it was. I couldn't budge it. Wayne, put in one tapcon and take your claw hammer and try to pull it out. The time the test takes will be worth the time saved of not putting in more than twice as many tapcons as needed. Try it, you'll see for yourself just how strong those little suckers are. Just 6 tapcons would equal 7200 pounds of shear force which is the major force on the sign.
[ November 24, 2014, 07:16 PM: Message edited by: Dave Sherby ]
-------------------- Dave Sherby "Sandman" SherWood Sign & Graphic Design Crystal Falls, MI 49920 906-875-6201 sherwoodsign@sbcglobal.net Posts: 5397 | From: Crystal Falls, MI USA | Registered: Apr 1999
| IP: Logged |
posted
Cordless impact drivers are a newer innovation than cordless hammer drills. They are like impact wrenches that mechanics use, delivering tiny blows to aid in rotation, in contrast to a hammer drill which delivers blows to help penetrate.
An impact driver requires less tool pressure than a regular driver. You don't have to bear down on the tool nearly as much, your battery will last longer, and there will be less of a tendency for the driver head to slip off the fastener, especially if you are using a Philips-headed Tapcon.
I tend to avoid mortar joints with fasteners, preferring to penetrate the brick instead. I've had too many screws that did not want to hold in mortar.
Another point: always clean the hole out, either with a round wire brush or a bulb syringe, and drill deeper than you need —at least a half inch. Concrete debris in the hole can easily seize the screw and break it off. I've also heard of rubbing the threads of the screw with a bar of soap or a candle to prevent seizing up, though I've never done it.
I seldom do installs anymore, but I think our installers use their cordless impact drivers far more often than their regular cordless drivers or their cordless hammer drills. I believe they also use the impact drivers in nonmasonry applications, such as in driving large lag screws.
The complaint I have always had about Tapcons was that they rust like crazy, even if you paint them. I've seen blue Tapcons rust in the box on the lumberyard's shelf! That was before I found out about stainless Tapcons. I also like the galvanized Hilti version of concrete screws. They seem beefier than the Tapcon brand and the galvanized coating is thick.
...........
Fourteen concrete screws on a 4x4 HDU panel seems a lot. I wouldn't use fourteen on a heavy lighted sign of that size. The weakest point on this installation will be the aluminum cleat rather than the fastener. Concrete screws have tremendous shear strength.
Brad in Kansas City
-------------------- Brad Ferguson See More Signs 7931 Wornall Rd Kansas City, MO 64111 signbrad@yahoo.com 816-739-7316 Posts: 1230 | From: Kansas City, MO, USA | Registered: Nov 1998
| IP: Logged |
-------------------- joe pribish-A SIGN MINT 2811 longleaf Dr. pensacola, fl 32526 850-637-1519 BEWARE THE TRUTH.....YOU MAY NOT LIKE WHAT YOU FIND Posts: 11582 | From: pensacola, fl. usa | Registered: Nov 1998
| IP: Logged |
posted
Dave...thanks for the very informative stats...I knew tapcons were trememndously strong and for that reason was wondering why so many were being recommended on so small and light of a sign...I was beginning to question all my installs on masonary...I feel better now...so thanks.
posted
You're welcome Rusty. I too believe in overkill to a point though. I'd rather use a few extra screws than file a claim with my extortion.... I mean insurance company.
-------------------- Dave Sherby "Sandman" SherWood Sign & Graphic Design Crystal Falls, MI 49920 906-875-6201 sherwoodsign@sbcglobal.net Posts: 5397 | From: Crystal Falls, MI USA | Registered: Apr 1999
| IP: Logged |
![[Wink]](wink.gif)
(impact driver). I'll try my old cordless first. Waiting on the weather. Here's a simulation of the job...
![[Smile]](smile.gif)
Printer-friendly view of this topic