Having trouble with concrete anchor bolts

[Nnorman1]

I’m installing my 2 post lift and 5 out of the 7 are tightening up okay but the other 2 just keep pulling up what do I do??

 

[Nnorman1]

 

[Nnorman1]

The one to the far right and the same one on the opposite side aren’t tight yet

 

[housewolf]

Glue them in. What I felt comfortable using and what I would suggest others using may be two different things, but they make epoxy specifically for this application

ETA; you must have had to whale on those q-bolts. I’ve set a gazillion of them and don’t recall ever mushrooming the end like that. Did you drill the right size hole?? You probably deformed the sleeve on the way down. In any event, epoxy will still work.

 

[paredown]

The other problem I have had is not drilling the holes quite deep enough, and there is not enough room for the center piece to go down enough to let the outside mushroom out correctly. Slightly oversize holes can be fixed with epoxy--standard practice now where bolts are mission critical.

 

[Renegade1LI]

All expansion anchors have a minimum setting depth that you must have. Also did you use the correct size bit? Also cleaning out the hole, but like like the depth or size is off. If you can remove the loose ones, verify size and depth is ok or switch to epoxy for those last two. There is also allot of thread sticking out on the other bolts, did you use the correct length bolt? We set them for about 3 threads above the nut.

 

[Nnorman1]

I used a cheap but that had a wide head on the top and thought they were going in too loose so ground a little off of the tip and think the expansion sleeves are maybe messed up now in the holes. How do I remove the wedge bolts now

 

[Nnorman1]

Glue them in. What I felt comfortable using and what I would suggest others using may be two different things, but they make epoxy specifically for this application

ETA; you must have had to whale on those q-bolts. I’ve set a gazillion of them and don’t recall ever mushrooming the end like that. Did you drill the right size hole?? You probably deformed the sleeve on the way down. In any event, epoxy will still work.

I’ve never done this much I thought they were supposed to go in hard but makes sense now

 

[housewolf]

I’ve never done this much I thought they were supposed to go in hard but makes sense now

For reference, this is mine. Some people take and use a sacrificial rod coupling to beat on to keep the end from mushrooming. If you use a large enough hammer you generally won’t have that problem.

 

[WoodTime]

You sir are in a pinch!

The only thing I could think of to possibly do that would be to in stall nuts all the way up the bolt to add beef. Then tap the bolts from all sides with a 2lb hammer trying to create a gap inside the concrete around the wedge and possibly wiggle them out. If you hit too hard it will snap the bolt.

 

[mike93lx]

How do you feel about moving your lift? Said somewhat tongue in cheek, but hopefully you can get them out.

If you can, epoxy will take care of it. Just follow the instructions carefully

 

[Nnorman1]

Glue them in. What I felt comfortable using and what I would suggest others using may be two different things, but they make epoxy specifically for this application

ETA; you must have had to whale on those q-bolts. I’ve set a gazillion of them and don’t recall ever mushrooming the end like that. Did you drill the right size hole?? You probably deformed the sleeve on the way down. In any event, epoxy will still work.

Think it’s just as strong? What do you suggest for getting them out

 

[mike93lx]

Think it’s just as strong? What do you suggest for getting them out

Are they blind holes or all the way through the slab?

Epoxy is very, very strong

 

[housewolf]

Think it’s just as strong? What do you suggest for getting them out

It’s worth a try to just pull up and maybe use a prybar but DON’T booger up the threads. Cut the mushroom off, take the nut off then stack a bunch of washers or cut a piece of pipe/conduit for spacers. Use the nut to pull them out as far as you can then a prybar after that. It may be easy, it may not but they will eventually come out but the sleeve might stay in the hole. If you through drilled them, just knock them down into the dirt

 

[TurnipTruck]

I just saw a YouTube where the guy had a bad anchor. He made a 1” thick bar with a hole on one end and a fulcrum in the middle. He would crank down on the anchor nut through the hole and wail on the other end with a large hammer to shock the anchor up, resetting/tightening the nut as he went.

 

[Rusted Nut]

If they are not tightening up, keep wrenching on them until they pop free. Then get some threaded rod (course) and epoxy the rod in. Epoxy holes are usually slightly larger than expansion bolt holes, for same size bolt, you can probably re-use the holes. You may have to drill them out a bit, like an 1/8” more. Make sure holes are clean, like blow them out with compressed air. If you can’t get them out, put a nut and washer on to keep bolt from sinking, and the drill out the center. Make sure you drill the full length of the bolt, then you can pull out what is left. No, it won’t be quick or easy.

 

[msharley]

HILTI makes an excellent two part epoxy....

 

[nadogail]

I guess you need to drop back and punt.

If the bolts pull out, blast the dust from the holes with compressed air then carefully apply epoxy. When using Hilti Quick Bolts in a thin slab you can drill through to soil.

You might call Hilti Customer support and ask to have a Technical Representative visit your job site.

 

[jrsavoie]

Do them one at a time.

Had a guy helping me, think he was going to cut a fat hog in the ****.
He drilled all the holes. Blew the holes out. Then put the epoxy in all of the holes.
When he got to putting the anchors in. He couldn't and had to start over.

 

[Renegade1LI]

I used a cheap but that had a wide head on the top and thought they were going in too loose so ground a little off of the tip and think the expansion sleeves are maybe messed up now in the holes. How do I remove the wedge bolts now

We do thousands of expansion bolts a year occasionally one or two get screwed up, it happens. The least destructive way is to core drill the bolt out to the next size.

 

[Nnorman1]

Are they blind holes or all the way through the slab?

Epoxy is very, very strong

Blind

 

[Nnorman1]

We do thousands of expansion bolts a year occasionally one or two get screwed up, it happens. The least destructive way is to core drill the bolt out to the next size.

Where can you get a core drill bit? Do you need a special drill for that ?

 

[coldh2o]

Do them one at a time.

Had a guy helping me, think he was going to cut a fat hog in the ****.
He drilled all the holes. Blew the holes out. Then put the epoxy in all of the holes.
When he got to putting the anchors in. He couldn't and had to start over.

Huh??

 

[Bill T]

i have seen lierally hundreds of thousands of concrete anchors installed. I work in a nuclear power plant as Mechanical and Civil Field Engineer (since 1983). Previous to 1983, I inspected nukes under construction (four plants). Next year will be 50 years of experience. Lots and lots of concrete anchors.There are many, many different ways to screw up concrete anchor installation. Please , please read up on the proper installation practices before trusting the anchors on something like a two post lift. All of the manufacturers have instructions available on the web describing how to properly install the anchors. They do this because of liability issues. Don't risk your life by purchasing cheap, off-shore anchors. I am sure there are plenty of folks on this forum who have had satisfactory service with the cheap anchors, but do you really want to take that chance? Spend the extra few dollars to get a quality anchor (like Hilti) from a reputable vendor.
Read all of the guidance from the vendors prior to installing the anchor. Know the requirements on perpendiularity, edge distance, etc. . Don't install anchors adjacent to cracks, Use a sharp bit when drilling the hole to get the proper diameter. Blow out the dust.
If you have installed wedge anchors and have to pull them, more than likely a cone of concrete will be pulled with the anchor. One way to avoid this is to use a very small bit, drill holes all aroud the anchor before pulling. The only a small area of the concrete surface will be disturbed. Repair the concrete by grouting. Do not install another anchor until the grout is cured.

 

[RaisedByWolves]

Glue them in. What I felt comfortable using and what I would suggest others using may be two different things, but they make epoxy specifically for this application

ETA; you must have had to whale on those q-bolts. I’ve set a gazillion of them and don’t recall ever mushrooming the end like that. Did you drill the right size hole?? You probably deformed the sleeve on the way down. In any event, epoxy will still work.

Wail, and yes, I was thinking the same thing.

 

[housewolf]

Wail, and yes, I was thinking the same thing.

Well, he may be wailing over it now

whale

verb (2)​

whaled; whaling
transitive verb
1
: LASH, THRASH

2
: to strike or hit vigorously

3
: to defeat soundly

wail​

1 of 2

verb​

ˈwāl

wailed; wailing; wails
Synonyms of wail
intransitive verb
1
: to express sorrow audibly : LAMENT

2
: to make a sound suggestive of a mournful cry

3
: to express dissatisfaction plaintively : COMPLAIN

 

[wssix99]

Call the manufacturer. They deal with this all the time. The bolts that are grabbing high will have lower pull-out strength, limited by the concrete. They have safety factors for all of this and may allow you to have one or two go long.

If not, the manufacturer has proper epoxy kits and recommendations for you. Not all epoxies are safe for this - even from reputable manufacturers. Epoxy has a creep quality that can cause some to fail under tension, which is the main force these bolts are under.

I also had a few of these and was able to pull them out and drill deeper with a quality bit. I then got longer anchor bolts and all was great.

 

[Spud McGee]

For removing the bad anchor, can you shim them like a padlock?
Loosen the nut to relieve pressure. Then slide/pound some shim stock down around the anchor to get between the anchor and the concrete hole. The shim stock leaves a smooth wall and keeps the anchors from grabbing anything. Then they pull out easier.

Seems like it would be worth the effort because it would reduce the risk of breaking the anchor off inside the hole.

 

[sgdawson]

Several people have mentioned blowing out the dust as one of the steps. It's really important to get the hole clean so the anchor bites well and sets firmly enough to fully expand as you torque it (DAMHIK). A layer of dust on the wall of the hole can allow the anchor to slip as it is tightened, so it just jacks itself out of the hole instead of setting.

Use a wand or some extension to make sure the dust is blown out the full length of the hole. I used a vacuum hose but still ran a tube to the bottom of the hole to get all the dust out.

 

[jrsavoie]

Huh??

It's a saying. If somebody is going to cut a fat hog in the ***, they are going to make things easier. It is usually used when the plan goes awry.