Discontinued use of drop in anchors

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shputnik

shputnik

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Utah
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Expert wirenut installer
I overheard a discussion regarding drop in anchors and there discontinued use. Something about an article that said they have been failing and that they were recommending a different type of anchor. The duct guys were installing an anchor where the screw tightened right into the concrete similar to a tapcon. And that the duct guys were no longer using a drop in anchor.

Does this sound familiar to anybody?
 
I never heard anything about that. I would be surprised if that were true, although there are better anchors than drop-in they're still used by plumbers and sprinkler fitters on our jobs. IMO for an anchor that has been around for decades when there is a failure is usually due to installation errors.
 
The anchors are possibly on the print for the job, or have evolved into 'common practice'.
The versions we have utilized (our faves) are:
Hilti 14 and Simpson Titen HD in a 3/8.
All these types generally require a hole to be bored then to some extent cleaned of drill debris and then the anchor literally threaded into the concrete.

The one hole clamps work better with the 3/16 Hilti but for whatever reason they snap off during the install so if needed a quick adjustment of the hole in the one hole clamp or the 4S box allows the 14 size to fit.

For unistrut or power strut slotted holes, the 3/8 Titens are the go to versions. The 1/2 inch size has a conflict with the socket fitting tween the channel ears.

Very good securing power for all the above applications. Impact type tool works better for driving the fastener. Hilti's driver for their screws in superior in my opinion which conflicts with my workers so I allow careful usage of the 18V battery powered impact drivers for the install. The Titens are placed with a battery or 120V AC powered 1/2 drive impact gun, 1/2 pneumatic also works too.

**
For the detail oriented folks:
Because I have traced difficult installs to worn concrete drill bits on the SIDES of the bit, I made some Go NoGo testers out of drill bushings.
I have em for the Hilti 3/16 and 14 sizes (these are nominal nomenclature but the dims are in the tech documents) and then in the callout drill bit sizes per the ASTM standard ....which I have these in the 3/8 and 1/2 sizes (we do pallet rack installs with the 1/2 size).

Since sometimes the drill person is ahead of the install person and if the bit is worn the expectation to get the job done is thwarted by the worn drill bit. Admittedly the drill bit being worn on the SIDES and having to be discarded is a bit of a disappointment - but this is the solution that I have found to accomplish the task predictably.

****
I believe you will find these data sheets to show decent load carrying performance in typical concrete - we have had some pushback a while ago to get these approved but isnt such a topic these days.
 
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hillbilly1 said:
Everybody likes Tapcons, but I’ve never had one hold that well, depends on the quality of the concrete. Never had an issue with drop in’s.
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Drop-ins also have the advantage that you can loosen or remove the bolt without affecting the hole in the concrete. If you take out a Tapcon it will never hold quite as well, even if you replace it with a new Tapcon. Also, Tapcons are relatively expensive for what you're getting (basically, a hardened screw).
 
I remember when lead anchors made the do not use list. We used them primarily on cinder block walls. But they were melting in fires. Never had a drop in anchor fail, though.
 
hillbilly1 said:
Everybody likes Tapcons, but I’ve never had one hold that well, depends on the quality of the concrete. Never had an issue with drop in’s.
Click to expand...
I like tapcons, just because they are quicker and good for light duty applications. strapping conduit of something like that. I wouldn’t depend on them for heavier items.

But for every one I’ve installed, I’ve had a backup plan of some type. either plastic or lead..
 
Jim M426 said:
I remember when lead anchors made the do not use list. We used them primarily on cinder block walls. But they were melting in fires. Never had a drop in anchor fail, though.
Click to expand...
On cinder walls I only use Ajs if the building is on fire they have bigger problems than my panel falling off the wall
 
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