anchoring 2 post lift, How did you do it? Options

[Calwaterbear]

Ok time to set-up my new/used 2 post lift. I poured a 14'X 25' pad, let it cure for 3 weeks.

So I will drill into the concrete and use 3/4 X 10'' wedge anchors. they will be 8" deep.

obviously the holes need to be drilled in exactly the right places, not only for each post, but also, the 2 posts have to be set at the exact width (dictated by the bar across the top, between the 2 posts).

so do i set up the posts, bolt on the top, then drill down through the feet?

Or use a template, put in the anchors, then drop the posts onto the anchors?

Bit of an issue is i am working alone, and even with a bobcat 763, i have not figured out a way to get the posts vertical yet, i plan on calling in my propane guy, who has a real live Ferrari crane on his service truck to lift em upright and position them.

Tech guys at Greg Smith say to drill the holes a couple of inched deeper than you will be anchoring at - so if you screw up, instead of having to cut off the anchor - you just drive it down in the slab. That seems like a good idea, but what if, while lowering the post, you miss and hit the top of the anchors, that would probably drive them down into the slab - No?

I'm probably overthinking this, but I'm hoping to draw from the experience of others who have gone before me on this venture!

[Calwaterbear]

Ok guys, got it done, thanks for all the advise, experience and inputs!

I went with 11" long wedge anchor bolts, following engineer and manufacturer recommendations. I have used epoxied in anchors in the past - but the engineer insisted the drive in wedge anchors are stronger. That makes sense, as the bolt is tightened - the "collar" expands - so it is putting pressure on all sides of the concrete, as opposed to counting on the glue to bond with the concrete. I'm sure either way is fine.

But 2 unexpected issues showed up

1. once the drill hole got deeper than 4 or 5 inches, the shop vac would not pull out the dust. I'm using a 14 gallon 6 hp shop vac. -
to clean out the holes to the complete 9", required I used compressed air with a long nozzle, down the hole, with the shop vac sucking up the stuff as the air got it moving. That worked really well.

2. instructions and advise reminded me to thread the nut on the top of the anchor, to use that as the surface the hammer would hit , to preserve the threads. That turned into a fairly significant issue, as the driving of the anchor lead to the nut essentially deforming the threads of the anchor (redheads - 3/4") once that happened, you could not back off the nut, nor drive it on any further. trying to do so resulted in the anchor spinning in the hole - because the nut wasnt putting and upward pull to set the anchor. My solution was to set up a simple fulcrum (2X4 on its edge) with a 16" long wrench as the lever. I essentially stood on the end - that levered up , providing upward pull, that started the anchor holding in the concrete. Then I was able to pull off the nut, chase the treads with a die, clean out the threads of the nut with a tap.

I tried using 2 nuts back to back, and aftermarket nuts to take the pounding - and that allowed for driving the anchor, and could be removed without levering, but it still deformed the threads enough that I chased all of the anchors, before putting on the nuts, and torqueing it down.

so I'm not saying I did it all correctly, I did the best I could - but I am confident that the lift is anchored securely, and will not cause any issues moving forward!

[Mark Henry]

Ok guys, got it done, thanks for all the advise, experience and inputs!

I went with 11" long wedge anchor bolts, following engineer and manufacturer recommendations. I have used epoxied in anchors in the past - but the engineer insisted the drive in wedge anchors are stronger. That makes sense, as the bolt is tightened - the "collar" expands - so it is putting pressure on all sides of the concrete, as opposed to counting on the glue to bond with the concrete. I'm sure either way is fine.

But 2 unexpected issues showed up

1. once the drill hole got deeper than 4 or 5 inches, the shop vac would not pull out the dust. I'm using a 14 gallon 6 hp shop vac. -
to clean out the holes to the complete 9", required I used compressed air with a long nozzle, down the hole, with the shop vac sucking up the stuff as the air got it moving. That worked really well.

2. instructions and advise reminded me to thread the nut on the top of the anchor, to use that as the surface the hammer would hit , to preserve the threads. That turned into a fairly significant issue, as the driving of the anchor lead to the nut essentially deforming the threads of the anchor (redheads - 3/4") once that happened, you could not back off the nut, nor drive it on any further. trying to do so resulted in the anchor spinning in the hole - because the nut wasnt putting and upward pull to set the anchor. My solution was to set up a simple fulcrum (2X4 on its edge) with a 16" long wrench as the lever. I essentially stood on the end - that levered up , providing upward pull, that started the anchor holding in the concrete. Then I was able to pull off the nut, chase the treads with a die, clean out the threads of the nut with a tap.

I tried using 2 nuts back to back, and aftermarket nuts to take the pounding - and that allowed for driving the anchor, and could be removed without levering, but it still deformed the threads enough that I chased all of the anchors, before putting on the nuts, and torqueing it down.

so I'm not saying I did it all correctly, I did the best I could - but I am confident that the lift is anchored securely, and will not cause any issues moving forward!