Tapcons loose in their holes

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May 10, 2005
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I have not used Tapcons much at all, have always used lead anchors. plastic anchors or sleeve anchors. For 3/16 dia Tapcons, the recommended bit dia is 5/32. First tried on concrete block and while the screw threaded in, the fit was loose. Tried again while holding the hammer drill as steady as I could to avoid enlarging the hole and still got the loose fit.

Today I was drilling into high strength concrete in a high rise apt ceiling using a Bosch Bulldog rotary hammer. I do not have a SDS 5/32 bit so I had the bit in a chuck mounted on the Bosch. The fit was really loose, so I gave up on the Tapcons and enlarged the hole to 1/4 and used a lead anchor and a wood screw.

Why can I not get a snug fit with a Tapcon?
 
I've honestly found tapcons suck if you need them to keep something from pulling out of concrete. For hanging something that sideloads them they'll hold plenty of weight, but for installation in a ceiling or a wall where the tapcon will be pulled against isn't a good use for them.

I've had the best luck with them by not predrilling a hole and instead just running them in with an impact driver. If I do drill a hole it's VERY small. I've had nothing but loose fits using the bit sizes they spec on the packaging.
 
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I have not used Tapcons much at all, have always used lead anchors. plastic anchors or sleeve anchors. For 3/16 dia Tapcons, the recommended bit dia is 5/32. First tried on concrete block and while the screw threaded in, the fit was loose. Tried again while holding the hammer drill as steady as I could to avoid enlarging the hole and still got the loose fit.

Today I was drilling into high strength concrete in a high rise apt ceiling using a Bosch Bulldog rotary hammer. I do not have a SDS 5/32 bit so I had the bit in a chuck mounted on the Bosch. The fit was really loose, so I gave up on the Tapcons and enlarged the hole to 1/4 and used a lead anchor and a wood screw.

Why can I not get a snug fit with a Tapcon?
Are you using the required Tapcon tool to install the Tapcons? I have installed 100's of Tapcons in concrete, blocks, bricks, etc., with the Tapcon tool and NEVER had a loose one.

 
I have not used Tapcons much at all, have always used lead anchors. plastic anchors or sleeve anchors. For 3/16 dia Tapcons, the recommended bit dia is 5/32. First tried on concrete block and while the screw threaded in, the fit was loose. Tried again while holding the hammer drill as steady as I could to avoid enlarging the hole and still got the loose fit.

Today I was drilling into high strength concrete in a high rise apt ceiling using a Bosch Bulldog rotary hammer. I do not have a SDS 5/32 bit so I had the bit in a chuck mounted on the Bosch. The fit was really loose, so I gave up on the Tapcons and enlarged the hole to 1/4 and used a lead anchor and a wood screw.

Why can I not get a snug fit with a Tapcon?
Hammer drilling will likely make the hole somewhat bigger.
 
Are you using the required Tapcon tool to install the Tapcons? I have installed 100's of Tapcons in concrete, blocks, bricks, etc., with the Tapcon tool and NEVER had a loose one.


No, I do not have the Tapcon tool. I watched the video and do not see how the tool helps with the fit. Seems to me the tool is to help avoid having to constantly switch the drill between drilling and screw driving.
Into block I could easily thread the Tapcon screw in with a 1/4 in nut driver. In the high strength concrete the fit was so loose that I could thread the screw in by hand, without any tool.
 
If the hole is correct, the fit is tight. If too much pressure is used the drill tip tends to walk and the hole is less accurate. Or if the drill is not frequently retracted to clean the concrete out, the hole will not be as accurate, in my experience.
I have a Makita sds hammer drill, it drills in tough concrete easily compared to my regular pistol grip drill/hammer drill. Night and day difference, the Makita just goes in like it's nothing in comparison. I think that makes a more accurate hole too.
 
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Not sure why you’re having this issue. I’ve been using the Tapcon tool that BlueOvalFilter posted above for years and never had a single loose fit problem. Maybe give it a try.
 
No, I do not have the Tapcon tool. I watched the video and do not see how the tool helps with the fit. Seems to me the tool is to help avoid having to constantly switch the drill between drilling and screw driving.
Into block I could easily thread the Tapcon screw in with a 1/4 in nut driver. In the high strength concrete the fit was so loose that I could thread the screw in by hand, without any tool.
The Tapcon tool has a set depth inside the head that only allows the Tapcon to go in so far as to NOT strip the hole. Look at it like some kind of torque wrench.
I have had said tool for YEARS and it works!
 
Tried something yesterday based on what JRed recommended and this is what worked for me. Drilled a hole in a concrete block with a 5/32 bit (recommended for 3/16 Tapcons) and then used a impact driver to drive in a 1/4 in Tapcon and got a nice tight fit. So tight that it would have been difficult to drive it in by hand. This Tapcon looks like it can take a lot of load, even pull out loads.

So this is what I will do going forward, drill a smaller than recommended size hole.
The Tapcon tool has a set depth inside the head that only allows the Tapcon to go in so far as to NOT strip the hole. Look at it like some kind of torque wrench.
I have had said tool for YEARS and it works!
I was drilling holes a bit deeper than what was needed, so the screw was not bottoming out.
 
Tried something yesterday based on what JRed recommended and this is what worked for me. Drilled a hole in a concrete block with a 5/32 bit (recommended for 3/16 Tapcons) and then used a impact driver to drive in a 1/4 in Tapcon and got a nice tight fit. So tight that it would have been difficult to drive it in by hand. This Tapcon looks like it can take a lot of load, even pull out loads.

So this is what I will do going forward, drill a smaller than recommended size hole.

I was drilling holes a bit deeper than what was needed, so the screw was not bottoming out.
Even if you drill the hole deeper than needed, the Tapcon tool is the PROPER way to install Tapcons.
 
Tried something yesterday based on what JRed recommended and this is what worked for me. Drilled a hole in a concrete block with a 5/32 bit (recommended for 3/16 Tapcons) and then used a impact driver to drive in a 1/4 in Tapcon and got a nice tight fit. So tight that it would have been difficult to drive it in by hand. This Tapcon looks like it can take a lot of load, even pull out loads.

So this is what I will do going forward, drill a smaller than recommended size hole.

I was drilling holes a bit deeper than what was needed, so the screw was not bottoming out.
That is also the CORRECT way of drilling a hole for a Tapcon.
 
But that is the recommended bit size, doesn't quite jive with your second last post about using a smaller than recommended bit size.
Wait, what? Where did I provide ANOTHER size bit?
Man, why don't you just buy a Tapcon tool/set and be done with it. Your negative replies are starting to get old. FAST! SMFH!
 
I've had generally good luck with Tapcon's. They hold up to hurricane winds here in South Florida.

However, if I have a loose one, the drilled hole was simply too big. That does happen, especially when the bit moves off center due to hitting a harder rock inside.

It's good to note that a 3/16 inch Tapcon has an ultimate tension load of 220 pounds in 1 inch of concrete block. That's not very much.

 
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