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Warren Lake
09-09-2023, 12:42 PM
does anyone know or has done an alternate to a concrete pad for a two post car hoist. At present have a garage floor that is broken up and needs a new pad but reality is the home may be sold to a developer and me moving to a better place.

Friend is selling me a two post hoist and either it goes to storage or wondered about strange as it may sound is there any reason that the posts could not be bolted to two 10 foot or more I beams sunk into the ground? they could be tied together as well. From logic seems if the beams were large enough and long enough there would be no balance issues front to back. Maybe a pad under each of those. I looked at it and there are no wires from side to side on the bottom but its not an assymetrical hoist, my understanding is more weight is to the front then.

I just wondered if there are any alternate ways to the usual six inch thick pad of some PSI concrete way that its done. Have watched some you tubes and seen enough guys cut the pad they have in the post area and repour stronger and better.

I think it will be best to hire to take it down as the friend is dealing with stuff now and dont want to put any more stress on him. Rotary brand 13 years old used in his shop for 3 years then shop was closed so maybe used the odd time for his hobby stuff if at all as he has two of them. 10,000 capacity 12 feet high. Said needs new lines on both Iooked and can see that but if any leaking its minimal like sweating a tiny bit. Hes kept them greased and serviced well even rust proof on the floor where the bolts are so no rust down there.

Tom M King
09-09-2023, 1:49 PM
The whole floor doesn’t need to be poured to the thickness required for the anchor bolts.

Tighten hydraulic lines with line wrenches, not regular wrenches.

Warren Lake
09-09-2023, 3:05 PM
thanks on both its symetrical and was told get asymetrical just read and it will make no difference to me ill put up with a bit of harder to get in and out . Appreciate that on the pad if this home is going to stay then would get a floor done, not there yet

Jim Becker
09-09-2023, 5:11 PM
In a few workshop builds I've seen on the 'Tube that are for automotive purposes and there was intention to install a two or four post lift, the specific locations for the posts were identified and "in those spots" the floor thickness was increased to properly support the lift. It was more or less like putting additional footers where the posts need to go. Since you need to replace the floor, you could choose to do that so you can use the lift at your current property and a good concrete contractors can easily make that happen when they setup for the pour.

Bruce Wrenn
09-09-2023, 5:18 PM
The concrete not only supports the weight of the lift, but also provides resistance against the posts toppling over. Remember, the car is balanced on the two posts. You could most likely replace only the area that would be under the foot print of the lift, plus an addition foot out to the sides. Add a VEE of #4 rebar into the slab to surround the anchor bolts to prevent them breaking loose from rest of the slab.

Bill Dufour
09-09-2023, 5:39 PM
Make two footings similar to a gib craneI would put a piece of sidewalk between them to keep it together. No idea what is required but I would suggest a 12" hole 5-10 feet deep with rebar cage to 3" from bottom and bolts welded on at top. Top is level with existing floor. Long depth is leverage to prevent tilting rather then shallow mass.
A real maker will have foundation plans signed off by their engineer. Failure to follow their plans will void warrantee. If crane is under twenty years old foundation requirements should be online for free.
BilLD

Jim Becker
09-09-2023, 7:33 PM
The concrete not only supports the weight of the lift, but also provides resistance against the posts toppling over. Remember, the car is balanced on the two posts. You could most likely replace only the area that would be under the foot print of the lift, plus an addition foot out to the sides. Add a VEE of #4 rebar into the slab to surround the anchor bolts to prevent them breaking loose from rest of the slab.
The lift manufacturer should have specifications for the required footings for their lift including horizontal size from center as well as depth.

William Lessenberry
09-10-2023, 12:20 AM
Got a tall ceiling? Remember the car hood and/or trunk will be higher than the lift posts when raised. I found that ceiling joists are stronger than Volvo hoods. :(:eek:
BillL

Warren Lake
09-10-2023, 1:03 AM
yes depending on where here its 11 one room and 12 between joists and easy to change if need be. 12 plus in another area. He told me the padded bar across the top is electronic and shuts it off if a car touches it so it stops it. he also showed me a mark on the hoist he goes up to and maybe that is not even up to the highest it can go. Intention is not for here but the next place. Like a four poster as well if I want to store. I left my truck on axle stands two winters ago. wheels off and all tarped up. 50 years old didnt appreciate being stored that way.

Jerome Stanek
09-10-2023, 6:48 AM
Use sana tubes like they use for street and parking lot lights.

Kyle Stiefel
09-10-2023, 9:32 AM
The lift manufacturer should have specifications for the required footings for their lift including horizontal size from center as well as depth.

As Jim mentioned. Each manufacturer has specific PSI, depth, rebar size recs based on lift capacity. I had planned for this in my garage pour and increased depth to 6" in the post areas. I actually have a Rotary on order as they are about a 10 week lead time, about another 6 weeks and hopefully lift off.

Warren Lake
09-10-2023, 12:44 PM
sono tube would make sense. Not sure many do it that way but get it would be good. One friend emailed he has six inches of concrete for all the four posters and didnt say PSI or. Another has fibreglass mixed into the concrete. I did that on parging and repair work,you can get some little fuzzies but final coat buried them. mechanic said make sure concrete extends past the pad and makes sense have to measure one location still, stored for now.

Tom M King
09-10-2023, 12:55 PM
Mohawk not only makes great lifts, but they have very thorough instructions online, including slab requirements. I expect almost any lift would be okay using Mohawk slab specs. I wouldn't get under a vehicle on one with less.

scroll down to page 62 or 3

https://mohawklifts.com/library/manuals/System_IA-10_1-2008.pdf

Jim Becker
09-10-2023, 3:57 PM
sono tube would make sense. Not sure many do it that way but get it would be good. One friend emailed he has six inches of concrete for all the four posters and didnt say PSI or. Another has fibreglass mixed into the concrete. I did that on parging and repair work,you can get some little fuzzies but final coat buried them. mechanic said make sure concrete extends past the pad and makes sense have to measure one location still, stored for now.
Again, you need to get the requirements for support from the lift manufacturer. Don't make assumptions unless you're going really, really stout...like way beyond what it might possibly require.

Warren Lake
09-10-2023, 6:03 PM
not going in yet i research stuff to death when I do stuff this being one of the places. Lots of life experience and smart people here. When moved will be in touch with the company he had all the manuals stored on the lift. He took care of his stuff.

Alex Zeller
09-11-2023, 12:53 AM
Do yourself a favor and get a couple jack stands. HF sells them for under $100 (last time I checked). Even though I made my slab to support my lift I still use one at each end of the vehicle just to be safe. On occasion I'll use them to support things, like if I'm swapping an axle on a truck. But I have a transmission jack for the lift that I'll use.

Jim Becker
09-11-2023, 9:39 AM
Jack stands are certainly an important safety item when one is using a jack to raise a vehicle for service. They are not really usable with the kind of lift that the OP is asking about becasue these lifts raise the vehicle several feet or more into the air. They do have some kind of safety pins/locks to insure they can't fall AFAIK, however.

Tom M King
09-11-2023, 11:28 AM
Alex must have been talking about an under hoist jack stand.

https://www.northerntool.com/products/strongway-high-position-2-ton-tripod-under-hoist-jack-stand-46208?cm_mmc=Google-pla&utm_source=Google_PLA&utm_medium=Automotive%20%3E%20Jacks%20%3E%20Jack%2 0Stands&utm_campaign=Strongway&utm_content=46208&ogmap=SHP%7cPLA%7cGOOG%7cSTND%7cc%7cSITEWIDE%7cOOT %7c%7c%7c%7c19587061651%7c148349408834&gclid=Cj0KCQjw9fqnBhDSARIsAHlcQYQiHKmW1vpnbmPiqa42 YEihJZZFdPf8r0Nh9RDe_jZ-peRoIcd-wZQaAug7EALw_wcB&gclsrc=aw.ds


https://www.harborfreight.com/2-ton-capacity-underhoist-safety-stand-61600.html?utm_source=google&utm_medium=cpc&utm_campaign=12144811130&campaignid=12144811130&utm_content=118356836353&adsetid=118356836353&product=61600&store=815&gclid=Cj0KCQjw9fqnBhDSARIsAHlcQYRxqJE13RIAA1DL42Zt tG5pnLW48RRNbx1C3VV3K0jK0fBs6Jjoaf4aAnONEALw_wcB

Jason Roehl
09-12-2023, 5:31 AM
What Tom linked are important to use under lifts if doing major component removal—engine, transmission, axles, etc. Many vehicles have poor weight distribution to begin with, and removing a large assembly can upset that balance enough for the vehicle to tip off the hoist’s pads. For instance, removing the rear axle of a pickup truck may be enough for it to tip forward due to the pickup already having an extreme forward weight bias.

Jim Becker
09-12-2023, 9:49 AM
THanks for the clarification, Tom and Jason. Good to know, not that I'll ever be involved with that kind of thing. :)

Alex Zeller
09-12-2023, 3:48 PM
My BendPak is an asymmetrical lift. I'm sure if I was a mechanic working on vehicles all the time and speed was important it might be different. The goal is to park the vehicle so it's as close to balanced as possible before lifting it (that's where a skilled mechanic excels). But I'm not great at judging vehicles to know how they are balanced. Pickups often front heavy for example. Harbor Freight has the same jack stands as Northern but cheaper. Northern looks like it would be a fun store to browse but there's none close to me where as there's several HF around.

Warren Lake
09-12-2023, 9:47 PM
thanks Alex thats good logic ill ask the retired guy when I see him sure he has them there as well. Custom car builder called today as I had said Asymetrical have the posts at an angle and he had said no they dont, Turns out they do his brother has them and they were angled. Read pluses and minus with each

My 92 year old neighbour saved articles for me from one car guy in te news paper one day reading lady took her car in to a well known name here and when she went to get it it had fallen off the lift and all the guys were bent over laughing, nice