Max Jax column bolt pattern.

[alan camby]

Good morning.
I am buying the 7000lb Max Jax in a month or two. Currently I am working on my floor to handle the columns and plan to pour concrete in the next week or two.
Can anyone please measure and confirm the bolt pattern max jax has on their website?
I want to make a template to hold the anchors in the concrete and need to confirm that the pattern is correct. The drawing says for "reference purposes only", which is concerning.
I wish I had the lift here to measure but wanted to wait a bit longer to see if they have another sale. Last year they had a St Patrick's day sale. I have to wait 28 days for the concrete to cure anyway.


I have a FB message in with max jax and will send an email also next week if they don't reply.


I will plan to make a new thread up on my install. I have taken over 50 pictures so far of just the concrete removal. I will definitely have plenty of pictures when I am done to make a detailed thread. This thread will include all the questions I have Googled and been unable to find. I started the demolition of my concrete 2 days ago and it was a lot more work than I ever would have imagined.

 

[PCustoms]

Does maxjax spec for embedded anchors?

Most installs I've seen are always anchored/bolted afterwards.

 

[alan camby]

I have

Does maxjax spec for embedded anchors?

Most installs I've seen are always anchored/bolted afterwards.

I agree that most posts and videos I have seen are anchoring after the concrete is cured. The absolute strongest way is to make a foundation that is embedded in the concrete. Instead of 4 or 5" of depth, you can go 6, 7 or 8" into the concrete.
My plan will involve 5/8-11 B7 threaded rod with 2 nuts at the base and a grade 8 washer sandwiched between the nuts.
I need to know the exact pattern though to make a template.

 

[Rusted Nut]

It seems you posted the template - no? Also, how are you planning on connecting your new footings to the surrounding slab, to distribute the loading? How deep are going?

 

[alan camby]

It seems you posted the template - no? Also, how are you planning on connecting your new footings to the surrounding slab, to distribute the loading? How deep are going?

Yes I did attach what they have on the website. I would just feel better if someone could confirm the dimensions. For "reference purposes only" has me concerned.
I am tying into the old concrete with rebar. Drilling Into the side and epoxing the rebar into the old concrete

 

[wssix99]

I want to make a template to hold the anchors in the concrete and need to confirm that the pattern is correct. The drawing says for "reference purposes only", which is concerning.

You should follow the instructions and use the anchors they provide. Embedded anchors have different failure modes than the wedge and/or epoxy anchors that MaxJax provides and are likely not safe to use. (If they were safe to use, you would be given the option and the tools needed to use them.)

 

[mike93lx]

I wouldn't try to template something like that without the lift on hand, regardless of what another member here measures their's to be

 

[PCustoms]

I wouldn't try to template something like that without the lift on hand, regardless of what another member here measures their's to be

OP's next thread "Can I redrill my MaxJax base?"

 

[Rusted Nut]

Yes I did attach what they have on the website. I would just feel better if someone could confirm the dimensions. For "reference purposes only" has me concerned.
I am tying into the old concrete with rebar. Drilling Into the side and epoxing the rebar into the old concrete

Have MaxJax confirm, they may have changed dimensions from what someone here has. Personally I would go way deeper with a pad, doweling into a 4” slab will not give you much for load distribution, and good chance the dowels could pop the top 2” off the existing slab, leading to failure.

 

[alan camby]

Have MaxJax confirm, they may have changed dimensions from what someone here has. Personally I would go way deeper with a pad, doweling into a 4” slab will not give you much for load distribution, and good chance the dowels could pop the top 2” off the existing slab, leading to failure.

I am making the concrete slabs larger than what maxjax requests. It is 13" deep. They say 12".
The hole in the concrete is 3'×4'. Their directions say 3'x3'.
They don't even call for the rebar to pin to old concrete slab. I got all that from the bendpack site for larger 10k lifts.

 

[alan camby]

Have MaxJax confirm, they may have changed dimensions from what someone here has. Personally I would go way deeper with a pad, doweling into a 4” slab will not give you much for load distribution, and good chance the dowels could pop the top 2” off the existing slab, leading to failure.

What model do you have? The Danmar M6, Bendpack M6K, or the newer M7K?

 

[Rusted Nut]

I am making the concrete slabs larger than what maxjax requests. It is 13" deep. They say 12".
The hole in the concrete is 3'×4'. Their directions say 3'x3'.
They don't even call for the rebar to pin to old concrete slab. I got all that from the bendpack site for larger 10k lifts.

I don’t have a MaxJax, so can’t help there. Essentially what you are planning, is to set the lift on two 3’ pads. You will get a bit of restraint from the your existing slab sandwitching the pads, and maybe a bit restraint from doweling into existing slab; but I certainly wouldn’t get under a lift like that.

I read the attached concrete requirements from MaxJax, it only talks about slabs, not 3’ footings. I would assume any mention of 3’ footings, they would be integral to a slab.

Concrete Requirements for a MaxJax Car Portable Two-Post Lift.

MaxJax Is The Patented Portable Two-Post Lift Designed To Fit In Your Garage Or Automotive Professional Shop.

www.maxjax.com

 

[alan camby]

I don’t have a MaxJax, so can’t help there. Essentially what you are planning, is to set the lift on two 3’ pads. You will get a bit of restraint from the your existing slab sandwitching the pads, and maybe a bit restraint from doweling into existing slab; but I certainly wouldn’t get under a lift like that.

I read the attached concrete requirements from MaxJax, it only talks about slabs, not 3’ footings. I would assume any mention of 3’ footings, they would be integral to a slab.

Concrete Requirements for a MaxJax Car Portable Two-Post Lift.

MaxJax Is The Patented Portable Two-Post Lift Designed To Fit In Your Garage Or Automotive Professional Shop.

www.maxjax.com

I feel I am going above and beyond what they recommend. They do take about pouring new footing.

 

[alan camby]

I don’t have a MaxJax, so can’t help there. Essentially what you are planning, is to set the lift on two 3’ pads. You will get a bit of restraint from the your existing slab sandwitching the pads, and maybe a bit restraint from doweling into existing slab; but I certainly wouldn’t get under a lift like that.

I read the attached concrete requirements from MaxJax, it only talks about slabs, not 3’ footings. I would assume any mention of 3’ footings, they would be integral to a slab.

Concrete Requirements for a MaxJax Car Portable Two-Post Lift.

MaxJax Is The Patented Portable Two-Post Lift Designed To Fit In Your Garage Or Automotive Professional Shop.

www.maxjax.com

Reply # 2. I have spent 20 plus hours watching videos and reading installs over the last few weeks. I wouldn't get under all these maxjacks with the wedge anchors not grabbing the thin 4" concrete. Post after post of guys hammering the factory wedge anchors in the ground and going with the epoxy. Post after post of wedge anchors pulling up over time. I have set 1000's of wedge anchors and know how they work. Not a huge fan of these in 4" concrete. All the big equipment that really stresses a mount requires a new footing in the gound. Jib cranes don't allow wedge anchors. All the ones I assisted in installing required J bolts be captured in a new footing. I always find it odd how people don't seem to like a new footer with B7 rod in the ground. A few nuts and washers at the bottom and it will never come out without breaking the stud. These lifts are all about clamping force, not shear. You want the ancor to stay put, not require retorquing every month as it slowly pulls out. Seems the number one complaint with the maxjax is leaking hydrualics and anchors not taking hold. Most of the hydrualic issues are a lack of experience with NPT.

 

[Rusted Nut]

I agree that cast in place anchors would be superior to expansion anchors. My concern with your plan, is what if your vehicle is loaded off center. What holds those pads in place in an over turn situation? That’s why I personally would go longer, wider, deeper.

 

[mepstein]

Reply # 2. I have spent 20 plus hours watching videos and reading installs over the last few weeks. I wouldn't get under all these maxjacks with the wedge anchors not grabbing the thin 4" concrete. Post after post of guys hammering the factory wedge anchors in the ground and going with the epoxy. Post after post of wedge anchors pulling up over time. I have set 1000's of wedge anchors and know how they work. Not a huge fan of these in 4" concrete. All the big equipment that really stresses a mount requires a new footing in the gound. Jib cranes don't allow wedge anchors. All the ones I assisted in installing required J bolts be captured in a new footing. I always find it odd how people don't seem to like a new footer with B7 rod in the ground. A few nuts and washers at the bottom and it will never come out without breaking the stud. These lifts are all about clamping force, not shear. You want the ancor to stay put, not require retorquing every month as it slowly pulls out. Seems the number one complaint with the maxjax is leaking hydrualics and anchors not taking hold. Most of the hydrualic issues are a lack of experience with NPT.

I agree. I skipped the wedge anchors and went right to the epoxy. I read a lot of maxjax install threads and it seemed like half of them had wedge anchors that failed from day one or slowly loosened over time.

 

[alan camby]

They just started a sale today. I ordered!!
Sale is $500 off all packages.

 

[wssix99]

Not a huge fan of these in 4" concrete. All the big equipment that really stresses a mount requires a new footing in the gound.

A 2 post lift is mechanically different and functions differently. It uses the slab as a plate. The equipment you are familiar with has a foundation isolated from the slab. It is possible to install a 2 post lift like this, but its ridiculously expensive and unnecessary.

10's of thousands of 2 post lifts are in use every day in this country in professional settings - bolted to 4" concrete. ... you'll be fine.

These lifts are all about clamping force, not shear. You want the ancor to stay put, not require retorquing every month as it slowly pulls out. Seems the number one complaint with the maxjax is leaking hydrualics and anchors not taking hold.

You said it above. You've done thousands. Get a new drill bit, drill a clean hole, and the bolt won't loosen. All those videos you saw were done by rookies using cheap tools.

 

[alan camby]

I received my new Maxjax MK7 yesterday.
I immediately started working in my Floorplate.
The drawing on the maxjax site has metric and fractional dimensions. The fractional dimensions are rounded. The metrics are what you want to go off of.
The attached metric drawings are the most accurate.
Looks like the dimensions changed slightly on 4-21-2010 then never changed again. My lift still has the same bolt pattern and plate size as this drawing. I heard that Bendpack moved the plate back on the columns by 1.5" when they redesign them but as already started, the pattern is the same.
Just wanted to pass this information along if someone else needs to know.

 

[Monza Harry]

Alan I concure that a heavy separate slab has many "pros" and few "cons". I however am not a fan of untreated steel in cement [4140/(2) for "B7" is a great alloy]! They just don't play well together! (Rust issues), I would look for some M22/7/8" M19/¾" "J-bolts" for your application, or at least 1/8" (3mm) larger than the anchors supplied with your lift. I think larger is required as in a very quick search I couldn't find an alloy specification for hot dipped "J-bolts". Therefore added gerth should be mandated. Since you are adding a "base" undercut your existing slab considerably (4" min., 6"+ better). I prefere more smaller rebars in a staggered pattern even a couple on an acute angle from below. These are my thoughts [and only my thoughts, based on $#!+ I've seen and broke myself]. So this advise is worth what you paid for it, consulting a local professional is almost always a better plan! Use our shares to ask better/more/different questions. Harry

 

[alan camby]

Alan I concure that a heavy separate slab has many "pros" and few "cons". I however am not a fan of untreated steel in cement [4140/(2) for "B7" is a great alloy]! They just don't play well together! (Rust issues), I would look for some M22/7/8" M19/¾" "J-bolts" for your application, or at least 1/8" (3mm) larger than the anchors supplied with your lift. I think larger is required as in a very quick search I couldn't find an alloy specification for hot dipped "J-bolts". Therefore added gerth should be mandated. Since you are adding a "base" undercut your existing slab considerably (4" min., 6"+ better). I prefere more smaller rebars in a staggered pattern even a couple on an acute angle from below. These are my thoughts [and only my thoughts, based on $#!+ I've seen and broke myself]. So this advise is worth what you paid for it, consulting a local professional is almost always a better plan! Use our shares to ask better/more/different questions. Harry

Harry,
Thanks for the comment. I soaked the B7 in purple power for several hours then scrub brushed it with dawn soap. The rod was red loctited into grade 5 coupling nuts and torques to 90ft lbs. Once I add nuts and a plate at the base of the rod, everything will receive red iron oxide primer. If any rod were to fail, it will be contained under the 3/8"x16"x26" steel plate. The holes in the plate are drilled to 11/16". The plate will have its own b7 J-bolts to hold it down. Maybe I will add a few 18-8 threaded rods to the plate for good measure. The only welding involved will be nuts on the bottom of the plate for the plates retention. There will be no welding on the coupling nuts, grade 5 full nuts used as jam nuts, or the 5/8-11 threaded rod.
I realize all steel will eventually fail in concrete. I feel the moisture levels should be very low since this is sheltered in the middle of a pole barn.