2 post lift questions

[Mario149]

Evening all, I'm currently having a 3 bay garage built and am looking at potentially installing a lift in the middle bay so I can do basic stuff on my Caterham and our battered daily drive BMW battlewagon without having to fanny around with jacks etc. I know zero about this stuff, but it would appear a 2 post is the way to go. Only issue is that most of them appear to have a fixed width unless I am misunderstanding? These widths tend to mean the whole setup is of the order of 3.3m wide which is too much for our design (2.4m wide garage doors, plus say 7cm or so on each side extra before your in the next bay's "space".

Or have I got it wrong, and you can basically get them set up for whatever width works for you?

While I'm asking, any recommendations on lifts? Seems like £1k-£1.5k will get me one (assuming it will fit).

[GreenV8S]

I've seen 2-post lifts where each post is bolted down (no mechanical connection between the posts) which obviously can be spaced however you want. They do require strong enough floor, though. Don't know whether the width is variable on the connected type you're describing - no doubt the suppliers would tell you if asked.

[227bhp]

GreenV8S said:

I've seen 2-post lifts where each post is bolted down (no mechanical connection between the posts) which obviously can be spaced however you want. They do require strong enough floor, though. Don't know whether the width is variable on the connected type you're describing - no doubt the suppliers would tell you if asked.

How would they synchronise with each other?

[227bhp]

Mario149 said:

Evening all, I'm currently having a 3 bay garage built and am looking at potentially installing a lift in the middle bay so I can do basic stuff on my Caterham and our battered daily drive BMW battlewagon without having to fanny around with jacks etc. I know zero about this stuff, but it would appear a 2 post is the way to go. Only issue is that most of them appear to have a fixed width unless I am misunderstanding? These widths tend to mean the whole setup is of the order of 3.3m wide which is too much for our design (2.4m wide garage doors, plus say 7cm or so on each side extra before your in the next bay's "space".

Or have I got it wrong, and you can basically get them set up for whatever width works for you?

While I'm asking, any recommendations on lifts? Seems like £1k-£1.5k will get me one (assuming it will fit).

You might have to consider a bigger garage or a different type of lift. They are like that so you can get a car between them and the door partially open, also that the arms swing out and even though they are telescopic will find the cills or jacking points.

[Mario149]

227bhp said:

GreenV8S said:

I've seen 2-post lifts where each post is bolted down (no mechanical connection between the posts) which obviously can be spaced however you want. They do require strong enough floor, though. Don't know whether the width is variable on the connected type you're describing - no doubt the suppliers would tell you if asked.

How would they synchronise with each other?

Hydraulic apparatus is separate from the lift I believe, with a line running to each post from what I've seen

[GreenV8S]

227bhp said:

How would they synchronise with each other?

I think there's some hydraulic cleverness in the power pack. I don't know how it works, but I visualise it as two positive displacement pumps mechanically linked.

[227bhp]

GreenV8S said:

no mechanical connection between the posts.

GreenV8S said:

I visualise it as two positive displacement pumps mechanically linked.

I see

[Krikkit]

If you're thinking of a 2-post lift you need to make sure the concrete floor slab is thick enough - otherwise they're in danger of dropping through.

A lot of them have a fixed width, but come as two separate posts until they're fixed down (i.e. you don't need a 3.3m door)

[voicey]

Krikkit said:

If you're thinking of a 2-post lift you need to make sure the concrete floor slab is thick enough - otherwise they're in danger of dropping through.

+1. You may find the additional cost of laying the thicker slab to be expensive.

If it's just a bit of home mechanics then I'd get the slab done so a scissor lift can be sunk into it. You can get scissors that lift to full height as well.

[Buzz84]

Mario149 said:

227bhp said:

GreenV8S said:

I've seen 2-post lifts where each post is bolted down (no mechanical connection between the posts) which obviously can be spaced however you want. They do require strong enough floor, though. Don't know whether the width is variable on the connected type you're describing - no doubt the suppliers would tell you if asked.

How would they synchronise with each other?

Hydraulic apparatus is separate from the lift I believe, with a line running to each post from what I've seen

Alternatively, my workplace has twin post lifts that are all electric screws for lifting. they have a sensor in both posts for the height to make sure they go up equally. you can definitely position these lifts as far apart or as close as you may need as there is only cables running between them.

the only issue you will come across having them closer together will be that you will not be able to open the doors to the vehicle as much or at all like you would be able too when the posts are further apart.

[Mario149]

Krikkit said:

If you're thinking of a 2-post lift you need to make sure the concrete floor slab is thick enough - otherwise they're in danger of dropping through.

A lot of them have a fixed width, but come as two separate posts until they're fixed down (i.e. you don't need a 3.3m door)

We have raft foundations and from memory we have about 30cm of concrete on top of our waterproof membrane, with the steel rebar at a (current) depth 15-20cm. On top of all this will, be another 2-3cm of levelling. Presumably this will be sufficient?

With regards to width - so if its purely to get the doors open, surely you could make it narrower and just push the car back and forth to position as necessary. Even with a width of 3.3m, I'd have probably still done that anyway so I didn't risk opening a door into the post accidentally. Unless I'm missing something?

edit to add pic:

Edited by Mario149 on Saturday 8th September 13:09

[GreenV8S]

Have you definitely ruled out a 4-post lift?

[Timbuktu]

That concrete will definitely be thick enough.

The trouble with a 4 post is the ramps can get in the way for some jobs and the wheels are not suspended when you raise the car up, you then have to raise it again to take them off which kind of defeats the object?

I'm going to install one of these in my new garage, but I've got 5m wide bays so I don't think space will be a problem.



Bradbury H2401B

Edited by Timbuktu on Saturday 8th September 19:18

[Uggers]

How big/heavy is the BMW?

Have you considered a single post lift?

https://www.automotechservices.co.uk/products/7521...

[alabbasi]

GreenV8S said:

I've seen 2-post lifts where each post is bolted down (no mechanical connection between the posts) which obviously can be spaced however you want. They do require strong enough floor, though. Don't know whether the width is variable on the connected type you're describing - no doubt the suppliers would tell you if asked.

What?

If you're installing a 2 post lift, you're going to lose a lot of space on either side. It might be worth it or not to you. They are going to be a fixed width as the cables have run either over or under the car. If over the car, you'll need to make sure you have the height too.

The concrete thickness and strength is really important so make sure you can safely anchor lifts.

2 post lifts are the most versatile because you can get under the car while the wheels are off and swing a hammer. If you have a space constraint, you can consider a scissor lift which lifts the car by the wheelbase. You can still remove the wheels but you're not going to be able to get under the car. 4 post lifts are only really ideal for storage and transmission work.

Edited by alabbasi on Saturday 8th September 16:19

[bearman68]

OK, I have 5.5 x 9mm wide bays, and space is at a premium with a 2 post lift.

1) 30cm of good quality concrete will be enough. Spec a better quality than really needed. it's bugger all extra in cost but much better for a worshop floor. I think mine is RG 25(?????) Someone will know concrete specs better than me.
2) A 2 post lift is a pain if you're working inside the car.
3) It doesn't look like you have enough height in you garage as I see it. You need what - about 4 metres of clear space, and it looks like your eves are less than that. Don't forget the bonnet and tailgate take up loads of height, and it's a pain to keep opening and closing them.
4) The normal hydraulic lift is kept level by big heavy duty steel cables.
5) Have you considered one of these. I've personally done everything you need to do on one of these, while sitting on a stool. No problem at all. It's a really flexible lift, and one I would recommend where space is a premium. The company is good to deal with as well.
https://www.ebay.co.uk/itm/Mobile-car-scissor-lift...

[GreenV8S]

alabbasi said:

GreenV8S said:

I've seen 2-post lifts where each post is bolted down (no mechanical connection between the posts) which obviously can be spaced however you want. They do require strong enough floor, though. Don't know whether the width is variable on the connected type you're describing - no doubt the suppliers would tell you if asked.

What?

Look at maxjax for example. I seem to remember BH showing something similar. You can even get mobile single column lifts which are wheeled into position around the vehicle and then work together to lift it. You'll need quite deep pockets for those, though.

[GreenV8S]

bearman68 said:

5) Have you considered one of these. I've personally done everything you need to do on one of these, while sitting on a stool. No problem at all. It's a really flexible lift, and one I would recommend where space is a premium. The company is good to deal with as well.
https://www.ebay.co.uk/itm/Mobile-car-scissor-lift...

I've been admiring those for a while. Do you need any special preparation on the floor? I guess the rollers are taking quite a lot of pressure.

[bearman68]

GreenV8S said:

I've been admiring those for a while. Do you need any special preparation on the floor? I guess the rollers are taking quite a lot of pressure.

They're bloody good. I used mine every day for 3 years with no trouble (but they are very simple). To prevent wear on the floor,I bought 2 strips of steel bar 150mm x 3mm, and made sure the wheels ran on those.
There is a risk that the wheels wear the concrete, and any split oils collect in the wear tracks, making the concrete soft, but a cheap bit of steel will solve that issue nicely.
I also welded small guides on my steel to re-centre the wheels every time it dropped flat - it has a tendency to 'walk' about otherwise. Sounds like it's a right 'mare, but it worked lovely for years, until we replaced it with a 2 post. One other problem with it - when you have a very heavy car on it - a 5 series or a Land Rover or something - the lift can need a little 'help' in the first part of the lift. I occasionally needed to use a trolley jack to assist in the first part of the lift on heavy cars.
I still miss it for work inside the car, under dashboards and the like. A 2 post is a pain for that.

It needs a little bit of thought to use it to replace a full exhaust, but after that, it's great. Clutch, engines, no problems. Brakes, and suspension it's ideal for. Interior work it's very good indeed, as you can lift the car up, and peek under the dashboard.
And it takes very little space. Brilliant bit of kit.

[Mario149]

Hmm...scissor lift might be a good shout. Feel like they're expensive for what they are though somehow.

Beam height is 2.1m, total height of garage is 4m, but the bays are 6m long, so thinking I should be able to get a car quite high if positioned correctly in the middle. The BMW is only 1.4m high itself, of which 15cm is going to be ground clearance so "won't count". That said, I know that I wouldn't be able to lift a car up so I can walk upright underneath, but my plan was to be able to get it say 1.5m off the ground so I could sit on a stool or similar underneath

I suspect it's going to come down to width - if I can find a 2 post lift where it's max external width is, or can be set to, ~2.55m, then I'd prob go with that. If not, then scissor would seem to be the way forward