racecougar
Well-known member
Why not post the answer? Some of us hold the degrees you seek.
Epoxy Anchors Yes/No
- Thread starter whejdak
- Start date
Thought one. Using a 1 inch diamond core bit to drill around the anchor. This can work, but may be tight. While the bit is labeled 1 inch, its internal clearance might be closer to 7/8 inch depending on wall thickness. Since a 5/8 wedge anchor and sleeve can be about 7/8 inches in outside diameter, it might not fit. A better option would be a 1 and 1/8 or 1 and 1/4 inch core bit to make sure you fully cut around the anchor. Mark your depth on the bit so you don’t go too deep.
Thought two. Can you fill the oversized hole with epoxy and install a new anchor. Yes. If you drill out a 1 inch or 1 and 1/8 inch hole, you can still use epoxy to install a new insert. You can use your 5/8 inch female-threaded insert and center it carefully in the epoxy. Insert it slowly and rotate to avoid air pockets. Make sure the hole is fully cleaned and blow out dust before epoxy goes in. Even if the hole is oversized, the epoxy will bond extremely well. You’ll lose official certifications due to the oversized hole, but it will still be far stronger and safer than the spinning wedge anchor.
Thought three. Drill through the anchor using a rebar-rated bit. This is a destructive option but it works. An SDS-plus hammer drill with a rebar-rated bit can chew through the metal anchor. This will ruin the bit and possibly damage the hole, but once it’s out, you can clean it up and refill with epoxy and a new insert. Expect a rougher hole and some concrete blowout.
Another option is to cut the anchor flush with the floor using a grinder, then move the hole slightly and epoxy a new insert 3 inches or more away from the original. You can fill the old hole with epoxy grout. Not ideal, but workable if your anchor spacing allows it.
If you have a core drill, the cleanest option is to use a 1 and 1/8 or 1 and 1/4 inch bit to cut out the spinning anchor, clean the hole, and install a new insert with epoxy. If that’s not an option, drilling through the anchor with a hammer drill is your next best bet. Cutting flush and patching is the last resort.
Thought two. Can you fill the oversized hole with epoxy and install a new anchor. Yes. If you drill out a 1 inch or 1 and 1/8 inch hole, you can still use epoxy to install a new insert. You can use your 5/8 inch female-threaded insert and center it carefully in the epoxy. Insert it slowly and rotate to avoid air pockets. Make sure the hole is fully cleaned and blow out dust before epoxy goes in. Even if the hole is oversized, the epoxy will bond extremely well. You’ll lose official certifications due to the oversized hole, but it will still be far stronger and safer than the spinning wedge anchor.
Thought three. Drill through the anchor using a rebar-rated bit. This is a destructive option but it works. An SDS-plus hammer drill with a rebar-rated bit can chew through the metal anchor. This will ruin the bit and possibly damage the hole, but once it’s out, you can clean it up and refill with epoxy and a new insert. Expect a rougher hole and some concrete blowout.
Another option is to cut the anchor flush with the floor using a grinder, then move the hole slightly and epoxy a new insert 3 inches or more away from the original. You can fill the old hole with epoxy grout. Not ideal, but workable if your anchor spacing allows it.
If you have a core drill, the cleanest option is to use a 1 and 1/8 or 1 and 1/4 inch bit to cut out the spinning anchor, clean the hole, and install a new insert with epoxy. If that’s not an option, drilling through the anchor with a hammer drill is your next best bet. Cutting flush and patching is the last resort.
Your comments fall right in line with my thoughts on this subject. And in the same order too.
I'm in the process now of removing the post from their bolted positions. I'm going to test and see if it is possible to pound the existing anchor down into the ground. I don't think that I drilled through the concrete to allow this, but it's worth the try.
In addition, I want to check the other nine anchors for their 90 # torque. I found other bolts that turned fairly easily but tight. I want to make sure that I don't have the same problem as with the spinner.
It's been several years that I have checked the tightness. I know, I probably should have checked every year.
I realized that the core bit has to be larger then 1" for the reasons you mentioned. At $75 a wack for a bit I was/am trying to find the correct size bit before buying. I can't get any info on the thickness (inside diameter) on the core bits.
And as far as the Hilti community..... they told me that they didn't do any oversized hole testing on the 200 caulk that I would use. But they did send me URL's for additional information. I think they did the right thing by not committing to my question. Legally, they could get into trouble I would guess. I'm talking about about a question that boiled down too........ Would more caulk in a larger hole be stronger or less strong then an anchor (epoxy anchor) in the hole that I drill out to l 1/8 or 1 1/4 inch. Their answers and comments were mostly about a threaded rod and not the female insert anchor.
I'm in the process now of removing the post from their bolted positions. I'm going to test and see if it is possible to pound the existing anchor down into the ground. I don't think that I drilled through the concrete to allow this, but it's worth the try.
In addition, I want to check the other nine anchors for their 90 # torque. I found other bolts that turned fairly easily but tight. I want to make sure that I don't have the same problem as with the spinner.
It's been several years that I have checked the tightness. I know, I probably should have checked every year.
I realized that the core bit has to be larger then 1" for the reasons you mentioned. At $75 a wack for a bit I was/am trying to find the correct size bit before buying. I can't get any info on the thickness (inside diameter) on the core bits.
And as far as the Hilti community..... they told me that they didn't do any oversized hole testing on the 200 caulk that I would use. But they did send me URL's for additional information. I think they did the right thing by not committing to my question. Legally, they could get into trouble I would guess. I'm talking about about a question that boiled down too........ Would more caulk in a larger hole be stronger or less strong then an anchor (epoxy anchor) in the hole that I drill out to l 1/8 or 1 1/4 inch. Their answers and comments were mostly about a threaded rod and not the female insert anchor.
Their reply was for me to look at some URL's that they supplied. When I looked at one, there were pages and pages of technical data that mostly didn't pertain to what I was doing.Why not post the answer? Some of us hold the degrees you seek.
Below you will find the response from Hilti that I received about strength and larger holes for epoxy female anchors.
Hello,
Thank you for reaching out. Core drilling out the existing anchor, as you mentioned, may result in a larger annular gap between the anchor element and the base material concrete than typically tested. For HIT-HY 200 V3, testing has not been completed for larger annular gaps than published.
The only anchor system that does have additional data for larger annular gaps is Hilti's HIT-RE 500 V3. I am linking some helpful resources regarding this anchor below:
Hello,
Thank you for reaching out. Core drilling out the existing anchor, as you mentioned, may result in a larger annular gap between the anchor element and the base material concrete than typically tested. For HIT-HY 200 V3, testing has not been completed for larger annular gaps than published.
The only anchor system that does have additional data for larger annular gaps is Hilti's HIT-RE 500 V3. I am linking some helpful resources regarding this anchor below:
- Technical Data starting on page 106 of Hilti's Anchor Fastening Technical Guide
- ESR-3814 for anchoring into concrete
- Designing Anchors with HIT-RE 500 V3 using Core Drilled Holes with Large Annular Gap
- Operating Instructions
Decisions are narrowing quickly.
I removed one post and found three out of five wedges have moved and can't be tightened up nor can they be pulled out.
The idea of drilling out is starting to look like a long unsure process.
One thing I was able to confirm is that I'll never be able to pound them through. They bottom out quickly with a few hammer hits. So drilling is the only option here.
I have the SDS drill and concrete bits so it looks like I am moving the posts to a new location.
I have very little confidence now that I ever installed these correctly to begin with.
Using 10 epoxy anchors makes me feel a lot better.
I foolishly spent a lot of money on items that I will not be using now. But, Safety is more important (even if I'm 78) for the use of this lift.
So, reading the installations for the MaxJax all over is in order. I have the room but need to start moving **** around again.
So here I go again on a new adventure. They never seem to end.
I removed one post and found three out of five wedges have moved and can't be tightened up nor can they be pulled out.
The idea of drilling out is starting to look like a long unsure process.
One thing I was able to confirm is that I'll never be able to pound them through. They bottom out quickly with a few hammer hits. So drilling is the only option here.
I have the SDS drill and concrete bits so it looks like I am moving the posts to a new location.
I have very little confidence now that I ever installed these correctly to begin with.
Using 10 epoxy anchors makes me feel a lot better.
I foolishly spent a lot of money on items that I will not be using now. But, Safety is more important (even if I'm 78) for the use of this lift.
So, reading the installations for the MaxJax all over is in order. I have the room but need to start moving **** around again.
So here I go again on a new adventure. They never seem to end.
It ***** having to scrap material and redo work, but let’s be real:
Spinning wedge anchors in unknown concrete vs. solid, properly installed epoxy anchors? That’s an easy trade when the goal is peace of mind every time you hear those rams push up.
You're not just moving the posts. You're giving yourself confidence in the foundation under them. At 78, you're still pushing forward, thinking critically, and doing things the right way, not cutting corners. That’s worth respecting.
Spinning wedge anchors in unknown concrete vs. solid, properly installed epoxy anchors? That’s an easy trade when the goal is peace of mind every time you hear those rams push up.
You're not just moving the posts. You're giving yourself confidence in the foundation under them. At 78, you're still pushing forward, thinking critically, and doing things the right way, not cutting corners. That’s worth respecting.
Thanks for those confident words of wisdom.
I am all set to begin the new installation. Just need to mark off the foot print and then start drilling again. I was shocked to see the cost of an SDS hammer drill from Bosch. I think it's an 11264 model electric cord. I bought it off of a guy who just finished drilling two post lift in his building and had no other use for it. That was several years ago. lot's of concrete bits and special tools for breaking up concrete.
I've drilled several holes with concrete bits but never a hole with a core bit and water. Glad I don't need to try it now.
I am all set to begin the new installation. Just need to mark off the foot print and then start drilling again. I was shocked to see the cost of an SDS hammer drill from Bosch. I think it's an 11264 model electric cord. I bought it off of a guy who just finished drilling two post lift in his building and had no other use for it. That was several years ago. lot's of concrete bits and special tools for breaking up concrete.
I've drilled several holes with concrete bits but never a hole with a core bit and water. Glad I don't need to try it now.
I would advise against using an impact. Unless your install manual says to... I had a MaxJax and I'm pretty sure it specifically stated not to use an impact gun.
I know that my Bendpak specifically states to not use an impact gun with concrete anchors.
duneslider
Well-known member
Not sure why they would say that. I did 50 wedge anchors the last couple days and hit every single one with a big old impact until it stops moving (milwaukee 1/2" this time) then spot checked them with a torque wrench. Success on all 50. We literally do thousands and thousands of anchors a year and there is no way we are gonna turn any by hand...
We also do a ton of epoxy anchors and we hit them with the impact as well...
You should not use an impact on an epoxy anchor.
If you use an impact before the epoxy has cured, the vibration can loosen or misalign the anchor. It can create voids or cracks in the curing epoxy and lead to a weak bond. This is especially risky if the temperature is low or the hole is oversized.
If you use an impact after the epoxy has cured, you can damage the threads inside the anchor. It can also shock the cured epoxy and over-torque the fastener before you can control it. The epoxy is designed to hold under steady pressure, not sudden impacts.
Some installers might use an impact with epoxy in high-volume work, but they usually work in very strong concrete and follow up with torque checks. That is not the case with a MaxJax where each anchor is safety-critical.
The correct way to use epoxy anchors is to drill and clean the hole, inject the epoxy from the bottom up, insert the anchor slowly while turning it, let it cure fully, and then install the bolts by hand or with a torque wrench. MaxJax calls for 90 foot-pounds.
Using an impact with epoxy anchors is not safe. It goes against the purpose of the anchor system.
If you use an impact before the epoxy has cured, the vibration can loosen or misalign the anchor. It can create voids or cracks in the curing epoxy and lead to a weak bond. This is especially risky if the temperature is low or the hole is oversized.
If you use an impact after the epoxy has cured, you can damage the threads inside the anchor. It can also shock the cured epoxy and over-torque the fastener before you can control it. The epoxy is designed to hold under steady pressure, not sudden impacts.
Some installers might use an impact with epoxy in high-volume work, but they usually work in very strong concrete and follow up with torque checks. That is not the case with a MaxJax where each anchor is safety-critical.
The correct way to use epoxy anchors is to drill and clean the hole, inject the epoxy from the bottom up, insert the anchor slowly while turning it, let it cure fully, and then install the bolts by hand or with a torque wrench. MaxJax calls for 90 foot-pounds.
Using an impact with epoxy anchors is not safe. It goes against the purpose of the anchor system.
Just because you do it doesn't mean that is what the manufacturer calls for, OR that it's safe.
The "professional" that put my lift in tried to do it too. But I stopped him. Pointed to the part in the manual the specifically states to NOT use an impact gun.
Then I wound up having to re-do pretty much everything myself because they were incompetent.
Here's a list:
1. Didn't bother to lubricate any of the shims
2. Put the hydraulic lines in backwards
3. Used plumbers tape instead of the sealant specifically called for in the manual (the sealant is expensive so I know why) This of course caused a clog in my screen at my pump that I didn't find until about 3 months later when I decided I would check their work on that too since they screwed everything up so badly on other things.
4. Short bolted two of the anchors. Instead of leveling the lift properly.
There's probably more, but I have tried to forget the experience.
I'd be interested to see any install manual that shows that it's acceptable to use an impact gun on concrete anchors.
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I'm pretty sure this is the exact same concept with the concrete.
I'm not an engineer so I can't say for certain... which is why each manufacturer has specific rules regarding the installation of their lift.
People can die because someone decided to take a short cut.
I installed the maxjax anchors (and the rest of it) without using an impact gun.
I'm not sure why anyone installing these things professionally wouldn't take the 20 or so seconds to thread the bolt down to the base before torquing it.
But of course they aren't going to be under the thing if it collapses so I guess who cares?
I hired "professionals" (a team of monkeys actually) to install my full-rise lift because I didn't have enough confidence doing the full-rise myself.
If I ever have to install any lift again I'll be doing it myself.... it matters more to YOU when you know you are responsible for your safety.
duneslider
Well-known member
All of our installs are permitted and inspected, sometimes the inspector has to be present while we anchor and follows us around watching and checking behind us. Sometimes they come in after install is complete and do spot checks and random pull tests.
Now, no idea what Max Jack sends with their stuff to use but if they don't want you using an impact that is their call but Hilti, dewalt, don't have a problem with it and we have not had a problem doing it and it passes all inpsections.
When we are doing epoxy these are usually installed before the steel is onsite. We drill and install all anchors before columns are even onsite and then set the base plates over the anchors when the steel arrives. Usually, one guy snugs up the nuts and a second follows behind torquing. We sometimes have to have an inspector onsite during drilling to make sure we are vacumming and wire brushing holes.
Our crews are doing hundreds of anchors a day, not some "team of monkeys".
Now, no idea what Max Jack sends with their stuff to use but if they don't want you using an impact that is their call but Hilti, dewalt, don't have a problem with it and we have not had a problem doing it and it passes all inpsections.
When we are doing epoxy these are usually installed before the steel is onsite. We drill and install all anchors before columns are even onsite and then set the base plates over the anchors when the steel arrives. Usually, one guy snugs up the nuts and a second follows behind torquing. We sometimes have to have an inspector onsite during drilling to make sure we are vacumming and wire brushing holes.
Our crews are doing hundreds of anchors a day, not some "team of monkeys".
Bendpak specifically states to not use an impact.
You are using their anchors so I would recommend following their instructions.
I looked up the MaxJax manual and it also specifically states to not use an impact.
See page 22.
For Hilti it looks like you have to have the " Adaptative torque module (M8-M12) " to use an impact.
For Dewalt, you are correct they allow for the use of an impact.
Either way the OP asked about MaxJax, you gave incorrect information that could have killed somone.
You are using their anchors so I would recommend following their instructions.
I looked up the MaxJax manual and it also specifically states to not use an impact.
See page 22.
For Hilti it looks like you have to have the " Adaptative torque module (M8-M12) " to use an impact.
For Dewalt, you are correct they allow for the use of an impact.
Either way the OP asked about MaxJax, you gave incorrect information that could have killed somone.
Finally drilled and installed the 10 epoxy anchors.
I had to drill down to 6 inches so that the anchors would level off with the pavement. In doing so, I cut through the bottom of the poured concrete. I had a hell of a time cleaning those holes out. Using an air gun and vacuum kept sucking up sand that was below the concrete.
Then when I tried testing whether the anchors would go down all the way, I kept running into something getting in the way ( more then likely stone/sand . I could have continued this clean and drill process forever. So, finally I stuck my finger down the hole, cleaned it out, and started injecting the epoxy. The first set of five holes left me with one hole with not enough epoxy. Those 11 oz bags are pretty measured out for the holes that need to be drilled.
Filling the holes was trial and error process. I obviously filled to high. Anchors all squirted out to the point that on the last of the first five, I ran out. Went to Home Deopot and had to purchase $27.00 tube to fill the last hole.
The next five , I got smarter and used the right about of epoxy to fill the holes. Last hole, just made it.
They are sitting now and tomorrow I'll replace the lift stands and torque them down.
ONE THING NOTED IN THE PROCESS. THE LIFT POSTS HAVE FOOTING HOLES THAT ARE OF DIFFERENT SIZES. MOST ACCEPTED THE 7/8 CONCRETE BID, FEW WERE SMALLER AND I HAD TO PILOT 5/8 HOLE FIRST. DAMN NEAR BROKE MY WRIST DRILLING 7/8 CONCRETE BIT IN THE SMALLER MAXJAX FOOTER HOLE.
Hoping that tomorrow will bring good news about alienment of anchors and post feet for clamping.
More tomorrow on the results.
I had to drill down to 6 inches so that the anchors would level off with the pavement. In doing so, I cut through the bottom of the poured concrete. I had a hell of a time cleaning those holes out. Using an air gun and vacuum kept sucking up sand that was below the concrete.
Then when I tried testing whether the anchors would go down all the way, I kept running into something getting in the way ( more then likely stone/sand . I could have continued this clean and drill process forever. So, finally I stuck my finger down the hole, cleaned it out, and started injecting the epoxy. The first set of five holes left me with one hole with not enough epoxy. Those 11 oz bags are pretty measured out for the holes that need to be drilled.
Filling the holes was trial and error process. I obviously filled to high. Anchors all squirted out to the point that on the last of the first five, I ran out. Went to Home Deopot and had to purchase $27.00 tube to fill the last hole.
The next five , I got smarter and used the right about of epoxy to fill the holes. Last hole, just made it.
They are sitting now and tomorrow I'll replace the lift stands and torque them down.
ONE THING NOTED IN THE PROCESS. THE LIFT POSTS HAVE FOOTING HOLES THAT ARE OF DIFFERENT SIZES. MOST ACCEPTED THE 7/8 CONCRETE BID, FEW WERE SMALLER AND I HAD TO PILOT 5/8 HOLE FIRST. DAMN NEAR BROKE MY WRIST DRILLING 7/8 CONCRETE BIT IN THE SMALLER MAXJAX FOOTER HOLE.
Hoping that tomorrow will bring good news about alienment of anchors and post feet for clamping.
More tomorrow on the results.
I used a Bosch 11624 Hammer Drill that I bought off of Craigs list years ago. What a monster of a machine.
Easy to use and well balanced for it's size. I was surprised to find that it didn't have a reverse, but never needed it.
I finally down loaded the manual for it. I was totally surprised to find what the selector switch on top can do. I only used in the hammer and drill position. I thought there was something wrong with the selector switch because it only seemed to work in hammer and drill.
Book showed how to use chisel and other tools that came with it in addition it showed how to make additional adjustments for hammering.
I thought that I was impressed when I bought it years ago..... Now I am really impressed.
This thing is a tank.
Easy to use and well balanced for it's size. I was surprised to find that it didn't have a reverse, but never needed it.
I finally down loaded the manual for it. I was totally surprised to find what the selector switch on top can do. I only used in the hammer and drill position. I thought there was something wrong with the selector switch because it only seemed to work in hammer and drill.
Book showed how to use chisel and other tools that came with it in addition it showed how to make additional adjustments for hammering.
I thought that I was impressed when I bought it years ago..... Now I am really impressed.
This thing is a tank.
I used a similar Bosch hammer drill. Effortless. After reading dozens of maxjax install threads and estimating that at least 25% of the anchors failed in the concrete, I bought epoxy anchors. Absolutely no regrets. I used a little painters tape around the holes before squirting in the epoxy so any excess just came off with the tape. I only use it for my old Porsche's. A 2000lb car isn't going to stress any lift but It's good to know the anchors aren't going to loosen over time.
Comforting to hear your story.
Yesterday I put the two posts back over the anchors. My instructions said 37 ft-pounds torque. Sounds a little light but I looked into that number a lot and seems correct. I use a bolt to help insert the anchors into the holes. It was a little tough turning the anchors in while getting them level with the concrete. I'll be putting the arms etc... etc... back on today .
Love those Porsche.
Yesterday I put the two posts back over the anchors. My instructions said 37 ft-pounds torque. Sounds a little light but I looked into that number a lot and seems correct. I use a bolt to help insert the anchors into the holes. It was a little tough turning the anchors in while getting them level with the concrete. I'll be putting the arms etc... etc... back on today .
Love those Porsche.