Another 2 Post Lift Anchor Thread

[bmdubya1198]

I installed an Eagle 2 post lift in my shop this weekend, and most of the anchors torqued down initially, however two did not. After lifting a couple cars, I retorqued them, and only 3-4 of the 10 were able to reach the specified 143 ft.-lb. This left me pretty concerned, obviously.
This is the typical two post floor plate lift, and calls for the standard 4" concrete. My floor is about 4-4.5 inches, and in good condition. The holes drilled cleanly, and upon driving down 3 of the loose anchors there was no cracking or crumbling (which was my concern when they continued pulling out).
Out of an abundance of caution (since I don't want this thing falling on me) I went ahead and got 10 new anchors (red head style), which I like better than the anchors included with the lift. This is the style I have currently https://www.mutualscrew.com/product...2MarZw20tyLMI_Cv4tesfQEYFRypGz1hoCFAQQAvD_BwE
And this is what I have to replace them with https://www.amazon.com/dp/B099JG1WDT/?tag=atomicindus08-20

Now, I was thinking of installing these with some anchoring adhesive. Once I started reading around, it seems that this is just as bad as oil discussions when it comes to discussing which method is best to anchor a lift. I've heard that you shouldn't use wedge anchors with epoxy/adhesive, or that wedge anchors are perfect 100% of the time, or that threaded rod and epoxy is the only way to go.
I'm afraid to send them down dry again, because I don't want to expand the holes even more, then have more problems with holding. I feel like hammering them down with a coating of adhesive would help it hold and bond to the concrete, then clamp is down at least part way after it gels so the anchor can bite. Then torque once it's cured. Once the adhesive has cured, I don't see why these anchors would hold any differently than threaded rod. I could be wrong, but that's why I'm asking on here before I do anything.

Bottom line... I want to feel safe under my lift, and I am absolutely not interested in moving the lift or pouring new concrete. I don't think either of these are necessary, but I am also completely new to this stuff. It seems some people go WAY overboard when it comes to lift installation, meanwhile there are others who have totally loose lifts and don't know much concern. Obviously safety is the number one concern here, but I like to be realistic. I also don't have thousands of dollars or several days to weeks to blow on this project... I rent my shop, and the lift itself was a big enough expense. Now it's costing me money not having it operating.

 

[no704]

How did you remove the original ones? When anchoring in to a slab I always drill thru, so the anchor can be driven thru.

Hard to help not seeing it. May be a good case for epoxy studs.

 

[Walkers]

I used Titen HD anchors instead of the wedge anchors. I don't know how many wedge anchors I have seen fail by pulling out when torqued, but it is a high number. Whichever you decide there will be someone along shortly to tell you how stupid you are and what a dangerous decision it was. Same with drilling through instead of stopping at the right depth.

 

[rockettauto]

They have very similar end strength if done well and in the right conditions. Although ITWs( redhead) conservatively calculated design loads for epoxy come close to tested ultimate pullout strength for their wedge anchors. So I'd call epoxy stronger

Cons for wedge:
Vibration
Wiggling
Imperfect holes
Imperfect concrete.

Cons for epoxy/other grout anchoring:

You have to select the right kind for the moisture content.

You have to get the hole clean.

This is why I prefer epoxy... There are far less errors and you're far more likely to achieve the tested strengths. It doesn't take much to compromise a wedge anchor installation, as you've seen.

Since you've already got compromised holes, don't want to drill new, and couldn't oversize even if you did without moving the lift.....epoxy/rod is basically your only option.

I wouldn't do both, it's simply untested. So who knows.

 

[bmdubya1198]

How did you remove the original ones? When anchoring in to a slab I always drill thru, so the anchor can be driven thru.

Hard to help not seeing it. May be a good case for epoxy studs.

One of them my dad actually pulled out, since he had been able to pull the center pin out. Took some wiggling, but it doesn't damage the hole. The other two I drove into the ground, since I had drilled all the way through on all of them for this reason. I get some pics later.

They have very similar end strength if done well and in the right conditions. Although ITWs( redhead) conservatively calculated design loads for epoxy come close to tested ultimate pullout strength for their wedge anchors. So I'd call epoxy stronger

Cons for wedge:
Vibration
Wiggling
Imperfect holes
Imperfect concrete.

Cons for epoxy/other grout anchoring:

You have to select the right kind for the moisture content.

You have to get the hole clean.

This is why I prefer epoxy... There are far less errors and you're far more likely to achieve the tested strengths. It doesn't take much to compromise a wedge anchor installation, as you've seen.

Since you've already got compromised holes, don't want to drill new, and couldn't oversize even if you did without moving the lift.....epoxy/rod is basically your only option.

I wouldn't do both, it's simply untested. So who knows.

I like the outlook on epoxy so far. Basically it seems that as long as I make sure it's as clean as possible, it will be just fine. Is there any specific type of threaded rod I need to use, or will anything cut it?

Also, is Sika Anchor Fix 2 an acceptable adhesive? This is what I bought to use, but if there is something better that I can source locally, I'd be happy to go with that instead.

 

[CraigStu]

I haven't done epoxy lift anchors but have used a lot on boats. My recommendation is check websites of lift manufacturers to see if there is a trend in recommended epoxies. I know exactly what I would use on a boat but would want recommendations from trusted sources in this specific use. Also, since you drilled through the concrete I'd shove a chunk of foam or backer rod or even wadded up paper towel down to the bottom of the holes so your epoxy doesn't just run out into the gravel below. When you are ready to do the epoxy/rod insert brush epoxy on the threads of the rod (leaving the top portion of the rod where the nut will be clean) as well as working it into the hole.

 

[c39er]

I installed an Eagle 2 post lift in my shop this weekend, and most of the anchors torqued down initially, however two did not. After lifting a couple cars, I retorqued them, and only 3-4 of the 10 were able to reach the specified 143 ft.-lb. This left me pretty concerned, obviously.
This is the typical two post floor plate lift, and calls for the standard 4" concrete. My floor is about 4-4.5 inches, and in good condition. The holes drilled cleanly, and upon driving down 3 of the loose anchors there was no cracking or crumbling (which was my concern when they continued pulling out).
Out of an abundance of caution (since I don't want this thing falling on me) I went ahead and got 10 new anchors (red head style), which I like better than the anchors included with the lift. This is the style I have currently https://www.mutualscrew.com/product...2MarZw20tyLMI_Cv4tesfQEYFRypGz1hoCFAQQAvD_BwE
And this is what I have to replace them with https://www.amazon.com/dp/B099JG1WDT/?tag=atomicindus08-20

Now, I was thinking of installing these with some anchoring adhesive. Once I started reading around, it seems that this is just as bad as oil discussions when it comes to discussing which method is best to anchor a lift. I've heard that you shouldn't use wedge anchors with epoxy/adhesive, or that wedge anchors are perfect 100% of the time, or that threaded rod and epoxy is the only way to go.
I'm afraid to send them down dry again, because I don't want to expand the holes even more, then have more problems with holding. I feel like hammering them down with a coating of adhesive would help it hold and bond to the concrete, then clamp is down at least part way after it gels so the anchor can bite. Then torque once it's cured. Once the adhesive has cured, I don't see why these anchors would hold any differently than threaded rod. I could be wrong, but that's why I'm asking on here before I do anything.

Bottom line... I want to feel safe under my lift, and I am absolutely not interested in moving the lift or pouring new concrete. I don't think either of these are necessary, but I am also completely new to this stuff. It seems some people go WAY overboard when it comes to lift installation, meanwhile there are others who have totally loose lifts and don't know much concern. Obviously safety is the number one concern here, but I like to be realistic. I also don't have thousands of dollars or several days to weeks to blow on this project... I rent my shop, and the lift itself was a big enough expense. Now it's costing me money not having it operating.

 

[rockettauto]

One of them my dad actually pulled out, since he had been able to pull the center pin out. Took some wiggling, but it doesn't damage the hole. The other two I drove into the ground, since I had drilled all the way through on all of them for this reason. I get some pics later.

I like the outlook on epoxy so far. Basically it seems that as long as I make sure it's as clean as possible, it will be just fine. Is there any specific type of threaded rod I need to use, or will anything cut it?

Also, is Sika Anchor Fix 2 an acceptable adhesive? This is what I bought to use, but if there is something better that I can source locally, I'd be happy to go with that instead.

All I can tell you is I used anchor fix 1 and regular threaded rod when I was building houses in hurricane country. It was in the engineers spec list. They only allowed cast in place or epoxied anchors.

 

[rockettauto]

Ok so not all.

Maxjax sells this with their anchor kits

Injectite


Anchorfix twos TDS has one directly comparable data point I saw quickly. 3/4 rod embedded 6 3/4.



It would appear anchorfix 2 is about 50% stronger than injectite.

Hardware store threaded rods from the concrete section are going to far exceed the tensile strength of any bonding and also of the concrete so Id say you're good there.

my two cents worth.

 

[wssix99]

I like the outlook on epoxy so far. Basically it seems that as long as I make sure it's as clean as possible, it will be just fine. Is there any specific type of threaded rod I need to use, or will anything cut it?

Also, is Sika Anchor Fix 2 an acceptable adhesive? This is what I bought to use, but if there is something better that I can source locally, I'd be happy to go with that instead.

You need to read the instructions. There is a lot of bad information on the internet, bad information on this site (mixed in with good), and some bad information in this thread. Some of that bad information can lead to consequences that we can't mention otherwise people will get into a wad an go off-topic.

All of these products have real engineers (experts) behind them that match the proper goods for the job and give the specifications for what you need to use. It's all in the instructions. Even if the package for the bolts or epoxy doesn't have the instructions on them, you can download the instructions off the web.

Epoxy (in general) sounds good, but it has some negative (flow) properties in tension - which it needs to resist in an application for a 2 post lift. Its important that if you use an epoxy, it is blessed by your lift manufacturer.

I installed an Eagle 2 post lift in my shop this weekend, and most of the anchors torqued down initially, however two did not. After lifting a couple cars, I retorqued them, and only 3-4 of the 10 were able to reach the specified 143 ft.-lb. This left me pretty concerned, obviously.

Call your lift manufacturer. They deal with this issue all the time and have (expert) engineering support for your problem. Typically, there is a factor of safety designed into the bolts, so they may be able to give you instructions on how to downgrade the torque for some of the bolts or may have alternate instructions/bolts you can use. They should also have an off-instruction sheet epoxy option for you to cover tough situations. If they call and don't give you specific answers, ask to talk to a supervisor until you get a straight answer. (Its there.)

 

[bmdubya1198]

I just realized it's actually Anchor fix 1 that I have. Either way, I will make sure to double check the info on the tube.
Thanks for the input, guys. I'll send an email to the manufacturer just to be sure as well.

 

[bmdubya1198]

Here are some pics of the holes: https://photos.app.goo.gl/qJt3EXFRAoJahNxA8

I attempted to install one of the new anchors, and those seem to be even worse. I started to feel like it was grabbing, then it eventually pulled pretty far up. Turns out the anchor itself stayed at the bottom of the hole, then the rod pulled out of it.

 

[gizardlizard]

I clicked on your Amazon link showing your replacement anchors. It shows installation torque at 110 foot pounds. Where did you get the 143 foot pound figure from?

 

[MikeC55]

You may have already read through it but this thread on MaxJax installs might be worth a read through. https://www.garagejournal.com/forum/threads/maxjax-installs-post-here.35763/page-28 I read too many stories that included problems with mechanical anchors and decided to go with epoxy. 6 years later, they are still rock solid, torque checks good. Some people had success with epoxy anchors after problems like you had. In some cases, the slab wasn't as thick as length of anchor and they stuffed a filler down in hole, just below bottom of slab to prevent epoxy from squishing out the bottom. I don't know if there are epoxy anchors available for 4 - 5 inch slabs, so if you decide on epoxy, you'll want to research this aspect a bit. I had to pour a new slab insert and went overkill at 12", so I didn't havve the anchor length issue. I bought my anchors from Garage Equipment Supply (https://www.wrenchers.com/maxjax-epoxy-anchor-bolt-kit-drop-in-epoxy-anchor-bolt-kit/) but back in 2014. This kit appears similar except I used a different epoxy.

 

[bmdubya1198]

I clicked on your Amazon link showing your replacement anchors. It shows installation torque at 110 foot pounds. Where did you get the 143 foot pound figure from?

The 143 ft lb figure was for the original anchors included with the lift. I didn't try to torque these ones to 143, I attempted 100 and wasn't able to get past 80 before it pulled up.

I'll search through that thread, I just need something that I can get right away that will do the job. The more I read, the more confused I get as to what to do... not helping when I'm in a pinch for time.

 

[mepstein]

I bought Simpson strong tie epoxy and the correct epoxy anchors for my maxjax. I called Simpson and spoke to one of the engineers. He assured me that using their product in my 4” concrete would provide for maximum bonding and tensile strength. I bought some round wire brushes on Amazon, chucked one in my drill and with a vacuum, mechanically cleaned the hole before applying the epoxy. I taped around each hole so any epoxy drips were super easy to clean up. The bolts torque in well and the lift feels very solid.
Short version- proper anchors, proper epoxy, done.

 

[rockettauto]

Oh , yeah. On the sika, the instructions on the tube ****....make sure you cut the conical portion of the tip down to flush....there's a little, I think red, cap in there you have to pull out with pliers or pry out with a knife.

I want to say they mention one of the two seals they use, but not the little cap.

If you don't catch it, you'll squeeze out about 20 percent of just one part of the epoxy and then it just gets impossible to squeeze.

Sounds dumb, but it's actually a little hidden.

I think it's the sika that's like that anyhow.

 

[gizardlizard]

If the mechanic anchors are pulling out at 80 foot pounds and your holes are the correct size, your concrete is weak. Most lift manufacturers I’ve seen recommend a minimum of 3000 psi concrete. I poured 4000 psi for my lift. This is exactly why some lift manufacturers advise against hand mixed concrete. It’s too difficult to control the mix and you can also get cold joints.

The 143 ft lb figure was for the original anchors included with the lift. I didn't try to torque these ones to 143, I attempted 100 and wasn't able to get past 80 before it pulled up.

I'll search through that thread, I just need something that I can get right away that will do the job. The more I read, the more confused I get as to what to do... not helping when I'm in a pinch for time.

 

[bmdubya1198]

If the mechanic anchors are pulling out at 80 foot pounds and your holes are the correct size, your concrete is weak. Most lift manufacturers I’ve seen recommend a minimum of 3000 psi concrete. I poured 4000 psi for my lift. This is exactly why some lift manufacturers advise against hand mixed concrete. It’s too difficult to control the mix and you can also get cold joints.

I doubt it's hand mixed, but I couldn't say for sure. It's an older building. There was previously a lift installed a few feet from where I installed this one, but I have no idea how long ago this was.
In the case of the new clip-style anchors, they seem to be the issue. It literally pulled the clip off and yanked the anchor upward.

That said, can anybody recommend using 5/8" anchors with epoxy? I'd like to stick with 3/4", but I'm planning ahead in case I'm unable to drill 7/8" holes for the 3/4" anchors.

 

[bmdubya1198]

The holes will allow for 7/8", so I will stick with 3/4" anchors. Now the next problem, WHERE do I find grade 5 all thread? I cannot find it anywhere. It seems pretty much everything I can find is grade 2. Also, it seems all thread is rated in many different grades than the standard 2, 5, and 8, and many of these rating compare different properties/specs. What do I use?

 

[rockettauto]

The strengths of 3/4 grade 2 rod itself wouldn't be matched by a 7/8 wedge anchor assembly until it was 8" deep in 6000psi concrete. The pullout strengths of the anchor assembly don't even come close to matching the limits of 3/4 grade 2 allthread.

The rod is just not the weakest link here.

 

[Ike Carlson]

I have been around a few two post lifts, and the anchor situation always bothered me. I have seen lifts with all the anchors loose and all of them tight, and some with 50/50. I hate working under a two post lift. I used to teach physics and that only makes it worse for me. If the load is balanced, it should be fine, but I see gross imbalance most of the time with 2 post lifts. I would take an in ground or 4 post any day.

 

[bmdubya1198]

The strengths of 3/4 grade 2 rod itself wouldn't be matched by a 7/8 wedge anchor assembly until it was 8" deep in 6000psi concrete. The pullout strengths of the anchor assembly don't even come close to matching the limits of 3/4 grade 2 allthread.

The rod is just not the weakest link here.

So you're saying that grade 2 would be acceptable here? I keep reading that grade 5 is the lowest to use for a lift, but with how these wedge anchors seem to hold, I think toothpicks in epoxy would be more effective.

I have been around a few two post lifts, and the anchor situation always bothered me. I have seen lifts with all the anchors loose and all of them tight, and some with 50/50. I hate working under a two post lift. I used to teach physics and that only makes it worse for me. If the load is balanced, it should be fine, but I see gross imbalance most of the time with 2 post lifts. I would take an in ground or 4 post any day.

I get the hesitation, I was nervous under this lift when I initially used it, but this was due to me knowing that the anchors didn't feel as tight as I'd like them to be. When properly balanced though, I haven't seen a lot of failures of 2 posts.
While a 4 post is obviously more stable and safer, it's not convenient. Can't do suspension work, can't easily drop engines/drivetrains from underneath, and there is a LOT more in the way. It's simply not practical in most cases. Not to mention the huge footprint. In my line of work, 2 post is the only way.

 

[rockettauto]

I'm saying, I'm not a structural engineer firstly. So this isn't worth much.

Secondly if it's me...Im looking at maxjax provided hardware kit and seeing they claim 16,500lbs pullout strength which is " like a safety factor of 12" which that part is extremely misleading but I digress.

Other companies spec 18000. With a 22000 shear.

Epoxy companies ( including ones packed with lifts) are claiming no more than but often far less than 29000 for 3/4 rod in 6 3/4 inches of 4000 psi concrete.

Grade 2 allthread 3/4" claims somewhere from 25000-29000 ultimate tensile.

Basically, if you have 7 inches of concrete and use some of the better epoxies the assembly approaches the strength of grade 2 but no matter what the assembly blows away provided wedge anchors.

For the most part ( and for every part with wedges) the assembly would be less than the strength of grade 2 rod.

Unless I had very thick concrete I wouldn't care about it being grade 2 because the assembly wouldn't match it's strength and even then I'd be figuring I'm just adding overkill compared to the installation specs of 16000lbs in 5" concrete. Even more overkill going up grades.

Unless I'm trying to triple the mfg specs and run 3/4 rod into 12+" of 5000psi concrete then I don't need grade 5 +

Depends on specifics but a grade 2 allthread is most likely the strongest part of the assembly. It's going to pull out or conically fracture the concrete before the rod itself would have an issue.

 

[Ike Carlson]

I'd like to know how they measured the pullout force. Concrete has little strength in tension and is only rated in compressive strength. I have seen anchors shear off in concrete without damaging the hole very much. I have also seen anchors pull out a cone shaped section of concrete when loaded.

 

[bmdubya1198]

That helps put my mind at ease, thank you. I ended up finding one 3' piece of grade B7 3/4" all thread at Grainger, couldn't find any more anywhere. I opted to use that for the 3 outer anchors, then use the grade 2 stuff on the two inners on each post. That way I at least have the stronger studs on the outside, where most of the load will be. Another tube of Anchorfix 2, a $40 7/8" drill bit, and I think I'm all set finally. This entire process has REALLY tested my patience.

On another topic, is it just me, or is every little part/bit of hardware, etc. that I ever need some absurdly specific specialty item that can only be found on McMaster or similar sites? Just went through this whole mess the other day with a control arm bolt. I've spent hours this week just driving around for hardware, between this lift and other stuff.

 

[Ike Carlson]

No joke, hardware is getting hard to find if it's not bulk bin stuff. I have been going to fastenal and paying rather high prices just to get what I need. The days of buying stuff off the shelf are coming to an end. Even car parts are not stocked like they used to be. Made-on-demand is the new green word. I have to make my own frame rails for my truck because they are not available anywhere.

 

[rockettauto]

Hardware has been a pain for a long time. Lots of things essentially not available. It's been the primary use of my mini lathe for years now.

 

[rockettauto]

I'd like to know how they measured the pullout force. Concrete has little strength in tension and is only rated in compressive strength. I have seen anchors shear off in concrete without damaging the hole very much. I have also seen anchors pull out a cone shaped section of concrete when loaded.

Most likely these for smaller stuff.

Concrete Bond Strength Testers, Anchor Testers, Pull-off Testers

Bond testers, pull-off testers and anchor pull-out testers accurately gauge the direct tensile or bonding strength between concrete and a coating or repair.

www.humboldtmfg.com

There's companies that do ASTM testing for bigger stuff and it's kind of similar but, steel frames and hydraulic cylinders.

Then the labs, I've seen a couple studies where it was basically rigged up in blocks they put into something that looked like a shop press but with the top part moveable.

 

[check251]

That helps put my mind at ease, thank you. I ended up finding one 3' piece of grade B7 3/4" all thread at Grainger, couldn't find any more anywhere. I opted to use that for the 3 outer anchors, then use the grade 2 stuff on the two inners on each post. That way I at least have the stronger studs on the outside, where most of the load will be. Another tube of Anchorfix 2, a $40 7/8" drill bit, and I think I'm all set finally. This entire process has REALLY tested my patience.

On another topic, is it just me, or is every little part/bit of hardware, etc. that I ever need some absurdly specific specialty item that can only be found on McMaster or similar sites? Just went through this whole mess the other day with a control arm bolt. I've spent hours this week just driving around for hardware, between this lift and other stuff.

Mcmaster-Carr has high strength comparable to grade 8 threaded rods

 

[bmdubya1198]

Yeah, so many things I think of in my head that would work perfectly in any given project, then I cannot for the life of me find in any hardware store. Everything has to be ordered. It ***** when it's something that I'll need once in a blue moon and a particular size, because it makes no sense to order it in bulk then pay for shipping on it. I try to get assortments of various things on Amazon, but of course that doesn't cover every possible size.
Auto parts, tell me about it... then comes the lack quality control in recent years.

 

[Ike Carlson]

There is no quality anymore. I went through a dozen chainsaw bars and still have not gotten a good one. Its crazy.

 

[Overhaulin63]

This thread certainly has a lot of smarter people than myself on this topic so I am hoping you can help me. I recently purchase a Tuxedo 10K two post and I have 6" of 3500 psi concrete with radiant heat. Before I poured the floor I routed the heat tubes outside two boxes where I planned to place a lift one day. I finally got a lift but the more I read the more confused and concerned I am about the best way to mount this lift.

Threaded rod and epoxy sounds like the best way to go, but if I drill through the concrete what do I do to keep the epoxy from pouring out the other end of the drilled hole?

Would the radiant heat create any issues with the epoxy over time?

Would I lose some strength by drilling all the way though the concrete?

Sorry for all the questions, I've never done this before and I am trying to do the best, and safest, way I can.

Thanks in advance for any assistance.

 

[wssix99]

Threaded rod and epoxy sounds like the best way to go, but if I drill through the concrete what do I do to keep the epoxy from pouring out the other end of the drilled hole?

In the face of your manufacturer recommending something else and the many downsides and complications of using epoxy (some of which you mention), why is it the way to go for you?

Lift manufactures typically reserve this solution for last-resort fixes or special applications.

 

[ratflinger]

Hilti (and maybe others) makes a specific glue for use when you drill though. Comes with a wire basket that goes in the hole and below the bottom. Some of the glue will squeeze out of the basket leaving hard, epoxy fingers below the base plus adhering to the wall of the hole. Epoxy is exteremly strong, you just have to follow the directions for hole cleaning, etc.

 

[ratflinger]

In the face of your manufacturer recommending something else and the many downsides and complications of using epoxy (some of which you mention), why is it the way to go for you?

Lift manufactures typically reserve this solution for last-resort fixes or special applications.

Maybe so, but may be cost. Wedge anchors are cheap compared to professional (Hilti, Simpson, etc) epoxies. I was a professional installer of heavy medical equipment for years, we often used epoxy because when done correctly it just doesn't fail.

 

[nadogail]

I'm saying, I'm not a structural engineer firstly. So this isn't worth much.

Secondly if it's me...Im looking at maxjax provided hardware kit and seeing they claim 16,500lbs pullout strength which is " like a safety factor of 12" which that part is extremely misleading but I digress.

Other companies spec 18000. With a 22000 shear.

Epoxy companies ( including ones packed with lifts) are claiming no more than but often far less than 29000 for 3/4 rod in 6 3/4 inches of 4000 psi concrete.

Grade 2 allthread 3/4" claims somewhere from 25000-29000 ultimate tensile.

Basically, if you have 7 inches of concrete and use some of the better epoxies the assembly approaches the strength of grade 2 but no matter what the assembly blows away provided wedge anchors.

For the most part ( and for every part with wedges) the assembly would be less than the strength of grade 2 rod.

Unless I had very thick concrete I wouldn't care about it being grade 2 because the assembly wouldn't match it's strength and even then I'd be figuring I'm just adding overkill compared to the installation specs of 16000lbs in 5" concrete. Even more overkill going up grades.

Unless I'm trying to triple the mfg specs and run 3/4 rod into 12+" of 5000psi concrete then I don't need grade 5 +

Depends on specifics but a grade 2 allthread is most likely the strongest part of the assembly. It's going to pull out or conically fracture the concrete before the rod itself would have an issue.

I don’t buy Grade 2 fasteners for anything where strength important, better grade fasteners are cheap insurance.

 

[nadogail]

Hilti (and maybe others) makes a specific glue for use when you drill though. Comes with a wire basket that goes in the hole and below the bottom. Some of the glue will squeeze out of the basket leaving hard, epoxy fingers below the base plus adhering to the wall of the hole. Epoxy is exteremly strong, you just have to follow the directions for hole cleaning, etc.

Hilti products are often imitated, but they are as good as you can get.

 

[wssix99]

Hilti products are often imitated, but they are as good as you can get.

They spend the most money on marketing to make us believe that.

 

[bmdubya1198]

With this thread newly bumped, I'll add that I've used my lift just about every day since installing it, and have had zero issues with the Sika epoxy. I check the torque once a month or so, and I've only had maybe two nuts need to turn the slightest bit to achieve the torque (75-80 ft lb) the first check. I did not have any movement the last time I checked them. No cracking in the concrete, and all is well.