MaxJax Anchor Installation - Concrete Thickness

[In My Garage]

My MaxJax came supplied with Wej-It PD-58 Power Drop anchors.

The reason for this post is due to my curiosity more than anything else, since I've gone with a totally different installation system for my MaxJax.


Looking at Dannmar's Instruction Manual as well as that from Wej-It, things didn't add up and performing a search didn't come up with anything.

The FAQs on Dannmar's site regarding the MaxJax calls for a minimum 4 inch concrete thickness...from their site:

Then in the MaxJax Instruction Manual, they state the following:

The above pic clearly shows solid concrete to beyond the end of the carbide drill bit.


From the Wej-It site, the PD-58 anchors call for a minimum 5 inch hole depth:

The question now is, does it matter if the anchors protrude "through" the concrete slab which would be the case based on the minimum required floor thickness, or do they have to be set into a "blind hole" which would mean a thicker floor requirement. And if they need to be in a "blind hole" as Fig 11 depicts, how much concrete, if any, is required beyond the end of the hole?

 

[47p2]

When I laid my floor 33' x 22' I put it in in 3 sections, two sections were 6" deep and the third section where the ramp was being fitted was 8" deep. The ramp was bolted to the floor with 6" bolts as recommended by the manufacturer.

does it matter if the anchors protrude "through" the concrete slab

If you do drill through the concrete you are at risk of penetrating and waterproof membrane that may be underneath

 

[In My Garage]

If you do drill through the concrete you are at risk of penetrating and waterproof membrane that may be underneath.

I'd be more worried about the effectiveness of the anchors and if they are designed to work in a through hole as well.

There was no waterproof membrane under my garage floor. It was bone dry.

 

[Daedalus]

I wouldn't worry about it; go with the lift mfg's recommendation, as they have vetted the hardware. If you follow the Wej-It instructions, they'll guarantee 16500 lbs of tensile capability. You won't need anywhere near that for your lift.

 

[c4cruiser]

I just measured one of the anchors I got with my MaxJax. The box label shows a part number of XPD-58 and a dimension of 7/8 x 3-7/8. The anchor body is slightly shorter than that at 3 -13/16".

The end of the three tabs that expand into the concrete floor as the anchor is tightened down is 3" from the top of the anchor. Adding another 1/8" per the instructions for the finished depth, it would seem that most garage floors should have enough depth to firmly set the anchor.

Now whether or not a given concrete floor is actually a specified thickness would depend on the poured depth of the area and how the crew that finished the floor made sure they didn't push too much concrete around to reduce the thickness of the slab. Hopefully, the pour would actually be a minimum of 4" if that was what was specified. My house plans called for a 4" floor thickness, but it's really hard to say if the contractor followed the specs. My garage floor is 19x32 and it's entirely possible that the slab thickness can vary by as much as an inch either way.

When I start to install my anchors, I'm going to drill a smaller pilot hole (something like 1/4") and measure my floor thickness. A small 6-8" inch piece of solid wire with a short 90 degree bend at one end should work. Drop it in the hole, move it to one side and pull up until it stops. Mark the wire at the floor, remove it and measure that distance. If it's at least 4", then the tabs will expand starting at an inch above the bottom of the slab.

 

[torq38]

My concrete is only 3" so I am cutting out a big enough section to mount and repor and install some metal rod also , was thinking of making a wooden templet and mounting anchors with the specified depth buy adding pipe or washes the same diameter as anchors then pushing in fresh concrete , any thought or ideas maybe someone has done before , THANKS

 

[JohnnyK8]

Here is a link for something similar.

http://edelweiss.smugmug.com/Category/Max-Jax-2-Post-Lift/

Search the MaxJax install thread and search and post there. Tons of information


https://r.tapatalk.com/shareLink?ur...&share_tid=35763&share_fid=20318&share_type=t

Maxjax Installs: Post Here


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