MaxJax Anchor Bolts

[heathy]

I'm trying to install my MaxJax and I can't seem to get the anchor bolts to bite into the cement.

I drilled the 7/8 hole, pounded down the anchor bolt 5/8 below the surface of the cement. The only way I get 100lbs of torque on the bolt is if the anchor comes up and hits the base of the jack. Not a good sign when I fail at bolt #1.

Any suggestions?

 

[427HISS]

Do you know for sure, that you have at least 4" of concrete ? Take a coat hanger, straighten it out and put a 1" 90 degree bend in the end. Mark it with your thumb and measure what you have. Let me know.

 

[heathy]

It's a little over 3.5 inches. I talked to Danmar about the depth before I pounded the anchor and they said it's good enough. Epic fail on my part it seems. I'll call Danmar again tomorrow to see what they say if no one else can give me ideas.

 

[C2C6Z06]

I had 3 1/2 inches and old concrete. the anchors seemed to hold but when I put the column on and shoved the column, it pulled them loose....so, I dug out 4' X 4' X 8" and re-poured...worked like a champ!!!

 

[427HISS]

Ultimately, that's the safe way to get it done and it really is pretty easy to do. I would also add some rebar for some extra assurance. Although I did not have to do any concrete work, I used the "cement epoxy" with the anchors. Worked great.

 

[heathy]

well the concrete seems to be in good shape, it took some effort to get the hole drilled.

I found these:

http://www.grainger.com/Grainger/items/3A495

http://www.grainger.com/Grainger/items/3A496

 

[bazar01]

well the concrete seems to be in good shape, it took some effort to get the hole drilled.

I found these:

http://www.grainger.com/Grainger/items/3A495

http://www.grainger.com/Grainger/items/3A496

Those were not the right ones.

These are:

http://www.grainger.com/Grainger/ww...on=Go!&QueryString=pd58&submit.x=9&submit.y=6

Try to epoxy the suspect ones. Drive the anchors down to the dirt and epoxy the new ones. Then just torque to 50 ft-lbs. Let it cure overnight then torque again to 100 ft-lbs. If it does not hold, pour new concrete or brace the two columns on the top.

 

[427HISS]

I don't think I would use the epoxy and re-torque the bolts twice. After it dry's and set's up hard, you don't want to crack (ect) the epoxy. I would just torqur it as close to 100 ft.lbs. as you can and leave it for a day or two. Also, I would only trust the anchors that they supply as they've tested all type's and found what works best. Again, ask them for advise.

 

[heathy]

Yeah I called them today. I'm pouring a new pad for it. Kinda ***** but such is life.

 

[FlameOut]

I thought it was normal for the anchors to pull up from the concrete and be flush with top of concrete. At least according to my directions they are

On page 12, step 9 it says: Install 5/8" x 2" hex bolt and flat washer then tighten the Column firmly to the floor until the Power Drop Anchor sets flush with the concrete surface"

 

[bazar01]

I thought it was normal for the anchors to pull up from the concrete and be flush with top of concrete. At least according to my directions they are

On page 12, step 9 it says: Install 5/8" x 2" hex bolt and flat washer then tighten the Column firmly to the floor until the Power Drop Anchor sets flush with the concrete surface"

No it's not supposed to pull up and be flushed with top of concrete.
The Wej-it directions is to drive the anchor 9/16" below the surface (embedment depth of 4-3/8" minus the anchor length of 3-13/16") then it only requires 4 complete installation turns on the bolt for it to grab the concrete. The thread pitch is 11 threads per inch. Four (4) turns on the bolt will pull the anchor up by about 3/8". That still leaves the anchor about 3/16" below the surface. If the anchor does not torque to 100 ft-lbs in 4 turns, the anchor will not hold the load, it failed.

 

[FlameOut]

No it's not supposed to pull up and be flushed with top of concrete.
The Wej-it directions is to drive the anchor 9/16" below the surface (embedment depth of 4-3/8" minus the anchor length of 3-13/16") then it only requires 4 complete installation turns on the bolt for it to grab the concrete. The thread pitch is 11 threads per inch. Four (4) turns on the bolt will pull the anchor up by about 3/8". That still leaves the anchor about 3/16" below the surface. If the anchor does not torque to 100 ft-lbs in 4 turns, the anchor will not hold the load, it failed.

I was just going by what the instructions say, and even the diagram shows it flush with the top of concrete. My anchors all pulled up and are flush and I have raised my car numerous times. I check the lift before and after each lift and it still appears to be securely anchored to the floor. Now I'm getting a little worried also

 

[ArthurPE]

chances are if the anchor did not spin, it 'bit'...
most applications you can't see the anchor, so you never know if it's flush...

the 'setting depth' is ~1/2", so subtracting 4/11" (4 turns at 11/" pitch) leaves about a tad over 1/8" (0.136"), so it's almost flush

 

[heathy]

Mine would just spin in the hole after a certain point. I rather pay the price to repour than to get squished.

 

[bazar01]

I was just going by what the instructions say, and even the diagram shows it flush with the top of concrete. My anchors all pulled up and are flush and I have raised my car numerous times. I check the lift before and after each lift and it still appears to be securely anchored to the floor. Now I'm getting a little worried also

If you have raised your car numerous times, then you are ok. Maybe your anchors are holding and still below the surface. Did you count how many turns the bolt took to achieve the required torque?
For more peace of mind, you can check really quick by moving the columns out of the way and do a visual.
You can further check the anchors by torquing the bolts without the column but using a 1/2 inch tall collar with a hole diameter of at least 1" and the supplied washer. The 1" hole will allow the 7/8" OD anchor to go past the surface and keep going until you hit 100 ft-lbs. If you don't hit 100 ft-lbs with the anchor already way past the concrete surface, then it failed to grab.

I had one or two suspect anchors, that was why I braced the top of the columns with 2 x 2 x 1/4" steel tubing for peace of mind.

Be safe!

 

[sberry]

I dont think much of the wedjit anchors. If the OP drilled 7/8 theree might be a problem if it was a 3/4 anchor???

 

[bazar01]

I dont think much of the wedjit anchors. If the OP drilled 7/8 theree might be a problem if it was a 3/4 anchor???

7/8" is the correct concrete drill bit size for the 5/8" Wej-it power drop-in anchor.

 

[heathy]

This was my garage concrete. As you can see it sucked.

 

[j.pickens]

Wow,
I've seen stronger sidewalks.
You are doing the right thing with the re-pour.
Would it be possible to set anchor bolts into the concrete for even better strength?

 

[NewShockerGuy]

Is there any downfall to driving the anchors down a little more.. IE: Put them down more knowing that when you start turning the nut it's going to come up, I'd rather drive it down a little lower knowing that it won't pull flush than to do it per the manufactures specs and having the anchor come up flush with the concrete or even a tad more? No?

-Nigel

 

[UPSHIFT]

Is there any downfall to driving the anchors down a little more.. IE: Put them down more knowing that when you start turning the nut it's going to come up, I'd rather drive it down a little lower knowing that it won't pull flush than to do it per the manufactures specs and having the anchor come up flush with the concrete or even a tad more? No?

-Nigel

Nigel,

You can pull them up to be 1/4" below the finished concrete surface. This will also assure you are getting a true torq on the bolts and not tightening them against the baseplate. You want to avoid going to low taking away the amount of threads in the recess anchor from the 5/8-11 X 2" Bolts that hold the column down. Good Luck !!

Gabe

 

[DonnyT]

I replaced the grade 5 bolts with grade 8 bolts and a 1/2 inch longer. My anchors locked in almost immediately with very little movement upward after tightening.