Hoist - what?!

Wow .... if you already have the shed, bugger fitting a 2post ... go the four! If your building the shed though ... plan ahead as you are!


That's a hell of a lot of work to make sure a car doesn't fall on you!

edit: looks like youtube links are broken.... But they basically cut a section out of the shed floor, jack hammer all the concrete out.... dig it deeper, fit reo bar .... then fill with concrete!

seeya,
Shane L.
 
schlitzaugen said:
Well, I didn't know anything about that but I did know about reinforced concrete as my father worked in the industry and often took me on building sites. back then however it was all bars and prefab. Today things are different:

https://www.aisc.org/contentassets/...plate-composite-wall-and-tie-bars--info-1.jpg

I'll be there when it goes down anyway.
Click to expand...

That looks like they are building walls, not floors! You would remove the metal sides and re-use for the next wall.
 
schlitzaugen said:
Well, I didn't know anything about that but I did know about reinforced concrete as my father worked in the industry and often took me on building sites. back then however it was all bars and prefab. Today things are different:

https://www.aisc.org/contentassets/...plate-composite-wall-and-tie-bars--info-1.jpg

I'll be there when it goes down anyway.
Click to expand...
Its it looks like it's intended for walls. If it's in the ground, what happens when the steel rusts away? Surely it only used above ground....... and not widely used in Australia.
Most industrial buildings these days use tilt panels. Laid up flat, rebar and mesh, poured and cured before delivery to site.
Lifted in place with a crane, the walls of a large commercial building can go up in one day.
 
I had my own retail workshop business about 40 years ago. Height was no problem, it was in a factory unit.
I chose a 4 post as the most versatile unit. I was into consulting and diagnosing, and needed more than just servicing, which is where I think a 2 poster comes into it's own - quick and wheels free for brake checks and rotations etc. Also a bit clearer to walk around and get underneath the 2 poster.
With the 4 poster I could adjust the 2 ramps with a spirit level to get very accurate levels fore/aft, left/right, for wheel alignment checking (adjusting nut/screw at the ends of the 4 cables at the top of each post). (Think Hudy set-up plate - RC joke). Also good for suspension checking and bush tightening at ride height, replacing shock absorbers at ride height, checking body heights. There was a strong cross plate between the 2 ramps, which could slide from front to rear, and I used a bottle jack to raise either front or rear for wheels free work, at which time I would lower the ramps (after jacking & supporting) to a comfortable work height, ie, ramps at about knee height. These days you can buy relatively cheap transmission hoists which have castor wheels on the floor, a long hydraulic ram supporting a cradle at top which supports and clamps to a transmission for removal and replacement with little or no lifting by the operator (whether you have a 2 post or 4 post). My mate currently has a quality 4 post hoist with 4 individual hydraulic jacks on a rail on the inside of each side ramp for quicker jacking of all wheels in a commercial environment.
The 4 poster is definitely more restrictive to move around, ducking under the side ramps or front/rear crossbeams, and only about say 800mm between the ramps to work between, although you can easily reach to the outsides of the car from that position.
I often used the hoist to park another car underneath, important in a small workshop, though I had to watch out for small hydraulic leaks from the ramp rams dripping on to the car below.
I was able to save a bit by installing it myself, 4 dynabolts per corner, using a plumb bob for "verticalness", and the 4 poster is inherently a more stable unit so concrete depth not a problem.
Mine was a Repco branded unit (back in the days when Repco was a proper trade supporting company), and was 3 ton capacity, single phase electric over hydraulic with cables supporting each corner. Each post had a ratchet type safety arrangement, the tension on the cable kept the pawl free of the "rack" but a cable failure would have let the pawl engage with the rack and prevent falling.

I like to think having a decent hoist in those years is why I am still lucky enough to have no back problems.

Cheers.
 
Last edited:
Buttercup said:
Its it looks like it's intended for walls. If it's in the ground, what happens when the steel rusts away? Surely it only used above ground....... and not widely used in Australia.
Most industrial buildings these days use tilt panels. Laid up flat, rebar and mesh, poured and cured before delivery to site.
Lifted in place with a crane, the walls of a large commercial building can go up in one day.
Click to expand...

That was just a picture to illustrate what the concrete people told me. I don't know what they do these days with concrete so it's all new. Tilt panels have been in use in the industry for a long time. I loved watching as a kid when the lifted them nine floors up like nothing.
 
schlitzaugen said:
That was just a picture to illustrate what the concrete people told me. I don't know what they do these days with concrete so it's all new. Tilt panels have been in use in the industry for a long time. I loved watching as a kid when the lifted them nine floors up like nothing.
Click to expand...

Just look at it. You have shown molds for making walls. I just looked up the molnar website ( quality hoist manufacturer ). Straight from there website.


hoist_floor.jpg


What you keep saying makes no sense at all for a floor slab. I've never heard of a metal plated concrete floor. How would you finish the floor? and stop the metal beneath the cement rusting away.
 
DoubleChevron said:
Just look at it. You have shown molds for making walls. I just looked up the molnar website ( quality hoist manufacturer ). Straight from there website.

What you keep saying makes no sense at all for a floor slab. I've never heard of a metal plated concrete floor. How would you finish the floor? and stop the metal beneath the cement rusting away.
Click to expand...

Shane, is that for a 2 post or 4 post Molnar? Or either?
 
Buttercup said:
Its it looks like it's intended for walls. If it's in the ground, what happens when the steel rusts away? Surely it only used above ground....... and not widely used in Australia.
Most industrial buildings these days use tilt panels. Laid up flat, rebar and mesh, poured and cured before delivery to site.
Lifted in place with a crane, the walls of a large commercial building can go up in one day.
Click to expand...
Our, Italian trained in Italy, neighbour was a foreman on these high rise building sites. He was horrified how here in Melbourne they pour concrete mix on rusted reinforcing steel. He told me that in Italy the steel was dipped into a cement slurry prior to concrete being dumped on it.
Wonder who is right? Suspect Joe Ferrari is:unsure:
 
DoubleChevron said:
Just look at it. You have shown molds for making walls. I just looked up the molnar website ( quality hoist manufacturer ). Straight from there website.


View attachment 135128

What you keep saying makes no sense at all for a floor slab. I've never heard of a metal plated concrete floor. How would you finish the floor? and stop the metal beneath the cement rusting away.
Click to expand...
This is exactly what I went through with mine. Meant that my $5,500 hoist ended up costing nearly $10k by the time we were able to use it. It was also a Molnar hoist.

Pretty sure that a 4-post hoist doesn't require anywhere near as much, since it's essentially a fancy shelf.
 
Demannu said:
This is exactly what I went through with mine. Meant that my $5,500 hoist ended up costing nearly $10k by the time we were able to use it. It was also a Molnar hoist.

Pretty sure that a 4-post hoist doesn't require anywhere near as much, since it's essentially a fancy shelf.
Click to expand...

Yep, IMO worth every cent when your standing under the car on the hoist swinging on a breakers bar. Like I said, I'd NEVER trust a two post hoist here .... not ever :eek:
 
Shane, like I said, I don't know exactly what they're talking about but that is what they said. They were a bit surprised when I said I wanted 20cm concrete too. I guess you could pour some concrete, then lay down that structure and then cover it with the rest of the concrete.
 
schlitzaugen said:
Shane, like I said, I don't know exactly what they're talking about but that is what they said. They were a bit surprised when I said I wanted 20cm concrete too. I guess you could pour some concrete, then lay down that structure and then cover it with the rest of the concrete.
Click to expand...

That sounds right, 200mm of re-enforced cement as the base pad under the hoist. Have a look at the "floor repair" section of the requirements above :)
 
schlitzaugen said:
Shane, like I said, I don't know exactly what they're talking about but that is what they said. They were a bit surprised when I said I wanted 20cm concrete too. I guess you could pour some concrete, then lay down that structure and then cover it with the rest of the concrete.
Click to expand...
I don't think so.
Flat steel plate will not bond adequately to the concrete. That would create planes able to separate and fail as a structure.
I believe there must have been a big misunderstanding. Maybe they thought you wanted retaining walls for a pit.
However even then, you would not put steel plate on the soil face. It would rust.
All reinforcement needs covering concrete, or protection from corrosive effects.

My 4 post hoist (able to be rolled around on wheels) is on 150mm of concrete in an aircraft hangar, where the floor is designed for aircraft point loads.
 
DoubleChevron said:
Just look at it. You have shown molds for making walls. I just looked up the molnar website ( quality hoist manufacturer ). Straight from there website.


View attachment 135128

What you keep saying makes no sense at all for a floor slab. I've never heard of a metal plated concrete floor. How would you finish the floor? and stop the metal beneath the cement rusting away.
Click to expand...

Why I queried it before, is that IMO, the above specs are not too onerous at all - if you are building a new shed.
The standard concrete depth in any workshop/shed would be 100mm. OK, another 100mm of roadbase compacted underneath it, not too unusual. The reinforcing mesh would not normally be included in a domestic shed, but something the concreters do every day, no problem.
The 200mm depth only comes into it for a repair or inlay job.

The reinforcing mesh adds a lot to the strength. When I had my backyard domestic shed/garage built about 30 years ago, I had a friend in a concrete family business - he recommended me (at small extra expense) to get 75mm reinforced instead of 100mm non-reinforced. It was a 6.0 x 9.0 metre floor in a colorbond shed. 2 reasons, it was just as strong or stronger, but mainly with reinforcement mesh the concrete would not crack, so avoided the necessity to put the usual grooves every 3 metres or so. It has a very smooth surface, I think that's what happens when they use steel trowel finish. It still looks good.

Following the above specs, and being a conservative fellow, if I was putting in a hoist I would probably be asking for a 150mm reinforced floor over a 100mm compacted roadbase underlay - and only in the end section of my shed where the hoist would go - ie, 3.0 x 6.0 metres.

I note the mesh is laid 30mm below the surface. I think this would be to get the dynabolts down into the reinforced area, not just the top surface.

Plenty of information in this thread for Schlitz to make some conclusions, I reckon.

Cheers.
 
Last edited:
It's not about reinforcing steel being 30mm from the top; it's about the cover from the bottom. You can get plastic chair supports to ensure correct cover, and don't omit reinforcement. If a hoist post has a cantilevered load, a bending moment can be transmitted to the floor.
 
Shane, I was answering your earlier comment about what makes sense in the context.

And yes, I have questions too about creating a "laminated" structure in which the layers are not really held together by anything (other than weight). But no, the concrete company understood correctly I wanted a slab, not some walls of any kind.

Not sure if in the end I actually do need 20cm thickness but I want it for other reasons so it will be 20cm thick. I am going to have some heavy machinery on top of it and I want it as rigid as possible. I also want the top surface to be polished so I can clean it easily. The hoist is a future proofing exercise, and it looks the question was worth it. At 20cm deep it looks like I can go for a two post hoist at some point in the future if I need/want to. I might go for a four post (I like them better) but who knows what other constraints I will have to meet?
 
Do you really mean polished ($$$), or steel trowelled?
Don't use less than 32 MPa at 28 days, as you need a hard surface. It isn't a footpath. To ensure the surface is suitable the slab should be wet cured. For a domestic project, just hose it daily.
 
I like the idea of concreting in the threaded rods for the two poster at the same time as the slab is laid.
IT just seems a lot neater than using any other type of fixing method, especially ones that require drilling into the slab and/or reo, and you can integrate it into the reo-bars/mesh
The only catch is you need to know what model hoist is going in so you can can make up the jig.
 
You must log in or register to reply here.
Top