Jacking up a car on grass

[Akhil Shastri]

Ok, I just wanted to get some thoughts on this from people who might have
had a bit of experience with it, I know its unsafe to plonk the jacks
directly onto the grass.

Suppose the grass is flat and you were to use a fairly thick and wide piece
of wood under the jacks/axle stands with chocks on the unraised wheels.
Would this be a safe way to do it? Are there other materials you can use
under the stands(bricks, slabs of concrete?) to make jacking the car up on
grass safe?

I have an area in my backyard that is concreted, but it is only really wide
enough to jack up one side of the car on, so one side would be on the
concrete and the other would have to be on grass.

Thanks!

[Smee]

sounds risky but as long as the grass is cut very short and the ground
underneath is firm and dry so long as you use a decent slab of concrete
or other heavy material then it hoepfully would be fine though I
personally wouldn't do it.

Post by Akhil Shastri
Ok, I just wanted to get some thoughts on this from people who might have
had a bit of experience with it, I know its unsafe to plonk the jacks
directly onto the grass.
Suppose the grass is flat and you were to use a fairly thick and wide piece
of wood under the jacks/axle stands with chocks on the unraised wheels.
Would this be a safe way to do it? Are there other materials you can use
under the stands(bricks, slabs of concrete?) to make jacking the car up on
grass safe?
I have an area in my backyard that is concreted, but it is only really wide
enough to jack up one side of the car on, so one side would be on the
concrete and the other would have to be on grass.
Thanks!

[sheik yerbouti]

Post by Smee
sounds risky but as long as the grass is cut very short and the ground
underneath is firm and dry so long as you use a decent slab of concrete
or other heavy material then it hoepfully would be fine though I
personally wouldn't do it.

flat ground, decent area of contact for the wood planks on the ground,
no problem. make sure they are decent solid planks, not chipboard or
anything.

if there's any hint of doubt about it, don't get under the car. you
need to be 100% sure when jacking.

[hippo]

Post by sheik yerbouti

Post by Smee
sounds risky but as long as the grass is cut very short and the ground
underneath is firm and dry so long as you use a decent slab of concrete
or other heavy material then it hoepfully would be fine though I
personally wouldn't do it.

flat ground, decent area of contact for the wood planks on the ground,
no problem. make sure they are decent solid planks, not chipboard or
anything.
if there's any hint of doubt about it, don't get under the car. you
need to be 100% sure when jacking.

Chunk of timber at least 75mm thick or even 40cm of railway sleeper
usually works well and won't shatter or crack (unless it's got termites!)
Concrete and bricks can & sometimes do. Stay safe. Cheers

[v]

Do it if u want to have a shot at getting onto the Darwin's list.....

Post by Akhil Shastri
Ok, I just wanted to get some thoughts on this from people who might have
had a bit of experience with it, I know its unsafe to plonk the jacks
directly onto the grass.
Suppose the grass is flat and you were to use a fairly thick and wide piece
of wood under the jacks/axle stands with chocks on the unraised wheels.
Would this be a safe way to do it? Are there other materials you can use
under the stands(bricks, slabs of concrete?) to make jacking the car up on
grass safe?
I have an area in my backyard that is concreted, but it is only really wide
enough to jack up one side of the car on, so one side would be on the
concrete and the other would have to be on grass.
Thanks!

[George W. Frost]

Post by Akhil Shastri
Ok, I just wanted to get some thoughts on this from people who might have
had a bit of experience with it, I know its unsafe to plonk the jacks
directly onto the grass.
Suppose the grass is flat and you were to use a fairly thick and wide piece
of wood under the jacks/axle stands with chocks on the unraised wheels.
Would this be a safe way to do it? Are there other materials you can use
under the stands(bricks, slabs of concrete?) to make jacking the car up on
grass safe?
I have an area in my backyard that is concreted, but it is only really wide
enough to jack up one side of the car on, so one side would be on the
concrete and the other would have to be on grass.
Thanks!

Use a slab of wood about 300 x 160 x 50,
don't use concrete, concrete will break under the pressure of the car's
weight based on the small imprint of the jack
bricks are smaller and will slip or sink in the dirt

[Dee]

pretty safe if you follow the previous replies, but i would also slid
the wheel under the car so if it does fall the wheel would catch it,
this saved my bacon once when a car fell off the stands, and I do it all
the time now no matter what i'm doing.

[Jac]

Post by Dee
pretty safe if you follow the previous replies, but i would also slid
the wheel under the car so if it does fall the wheel would catch it,
this saved my bacon once when a car fell off the stands, and I do it all
the time now no matter what i'm doing.

So was that a brown pants moment?
:-)

how far under the car were you?

Jac

[Dee]

Post by Jac
So was that a brown pants moment?

not really ... was a bit young and stupid back then, didn't realise how
close it was till much later ..

Post by Jac
how far under the car were you?
Jac

under the diff axle housing, feet pointing out the back tightning
tailshaft uni. the diff axle housing caught me across the chest and I
was just able to wiggle out .... thank god for 10" wide tyres :) we had
a tyre under the car on either side. good thing about using the wheels
is they don't damage the car or themself if things decide to move.

Car was sitting on dead flat concrete with proper car stands supporting
the diff. I was only using a small ringspanner to do the uni nuts , but
that sideways force was enough to rock it off the stands.

[John_H]

Post by Akhil Shastri
Suppose the grass is flat and you were to use a fairly thick and wide piece
of wood under the jacks/axle stands with chocks on the unraised wheels.
Would this be a safe way to do it? Are there other materials you can use
under the stands(bricks, slabs of concrete?) to make jacking the car up on
grass safe?

A piece of hardwood around 300 x 150 x 30 does for jacking on under
most ground conditions you can drive on (and ought live permanently in
your boot to cater for emergencies).

If you're looking for a more permanent setup to work under the car a
piece of 10mm steel plate is hard to beat. In the absence of safety
stands (or a suitable place to use them) sawn wood blocks are ideal,
particulary if you have a chainsaw and a suitable tree. I normally
look for ones around 400 mm diameter :)

Don't use bits of masonary (bricks and concrete).

--
John H

[The Raven]

Post by Akhil Shastri
Ok, I just wanted to get some thoughts on this from people who might have
had a bit of experience with it, I know its unsafe to plonk the jacks
directly onto the grass.
Suppose the grass is flat and you were to use a fairly thick and wide piece
of wood under the jacks/axle stands with chocks on the unraised wheels.

What sort of wood? The type of rubbish most people have laying around would
be totally unsuitable.

Post by Akhil Shastri
Would this be a safe way to do it? Are there other materials you can use
under the stands(bricks, slabs of concrete?) to make jacking the car up on
grass safe?

If I had to do it with wood, redgum would be a starting point provided it
really is stable.

Bricks are a no-no, solid or otherwise!

Concrete would be ideal but if you have a small section (eg. like a paving
tile) the jack could crack it and go straight through it at the worst
possible time.

Post by Akhil Shastri
I have an area in my backyard that is concreted, but it is only really wide
enough to jack up one side of the car on, so one side would be on the
concrete and the other would have to be on grass.

That's OK if you only want to jack one side and the grassed side is secured
with chocks and there is no chance of sliding/slippage.

For a little bit of added safety, slide a wheel under the car so if it does
fall the weight will go onto the rim. It may make the difference between
being crushed to death and surviving should the car fall.

Just be sure whatever you do is more than sufficient. You get no second
chance if the car falls on you and pops your head like a dropped
watermelon..........

[Antti]

Post by Akhil Shastri
Ok, I just wanted to get some thoughts on this from people who might have
had a bit of experience with it, I know its unsafe to plonk the jacks
directly onto the grass.

My preference is a solid piece of ply-wood (at least 20mm thick, at least
a foot square), unlike hardwood it has no grain and is a bit lighter for a
given strength. Whatever you do, just be sure that the load is not at an
angle where the jack may slip out sideways, dropping the car.

Antti

[Akhil Shastri]

Post by Akhil Shastri
I have an area in my backyard that is concreted, but it is only really wide
enough to jack up one side of the car on, so one side would be on the
concrete and the other would have to be on grass.

Thanks for all the advice, it seems that there is some concern by smee and v
over the safety of this setup while the others are suggesting some thick
large pieces of hardwood being reasonably safe.

I want to be 100% sure though, so as an alternative would this be a better
setup:

Concrete up the other half of the dirt patch enough to get the whole car on
with jacks on both sides and some concrete buffer on both sides to give
enough strength to the patch of concrete that will be supporting the jacks.
The type of concrete I would use would be the stuff you buy at Bunnings, the
"mix it in a wheelbarrow with water" type. A couple of questions with this
though, what thickness of concrete would I need to lay down and how much
buffer(extra concrete) would I need to lay on either side in order to ensure
enough strength to the concrete under the jacks?

As added security I liked John_H's idea of putting some 10mm thick steel
plates under the stands to spread the load a bit.

Would this type of setup be more adequate?

[Rainbow Warrior]

Post by Akhil Shastri

Post by Akhil Shastri
I have an area in my backyard that is concreted, but it is only really

wide

Post by Akhil Shastri
enough to jack up one side of the car on, so one side would be on the
concrete and the other would have to be on grass.

Thanks for all the advice, it seems that there is some concern by smee and v
over the safety of this setup while the others are suggesting some thick
large pieces of hardwood being reasonably safe.
I want to be 100% sure though, so as an alternative would this be a better
Concrete up the other half of the dirt patch enough to get the whole car on
with jacks on both sides and some concrete buffer on both sides to give
enough strength to the patch of concrete that will be supporting the jacks.
The type of concrete I would use would be the stuff you buy at Bunnings, the
"mix it in a wheelbarrow with water" type. A couple of questions with this
though, what thickness of concrete would I need to lay down and how much
buffer(extra concrete) would I need to lay on either side in order to ensure
enough strength to the concrete under the jacks?

Don't forget to add some mesh & possibly drill some bars into the existing
slab to stop the new slab falling away if it's not level ground.

Post by Akhil Shastri
As added security I liked John_H's idea of putting some 10mm thick steel
plates under the stands to spread the load a bit.
Would this type of setup be more adequate?

[Antti]

Post by Akhil Shastri
"mix it in a wheelbarrow with water" type. A couple of questions with this
though, what thickness of concrete would I need to lay down and how much
buffer(extra concrete) would I need to lay on either side in order to ensure
enough strength to the concrete under the jacks?

www.parksandplaces.act.gov.au/public/driveways.pdf

} 5.4.1 Residential Residential Driveway Pavements should be designed using
} AS 3727-1993 Guide to Residential Pavements, which covers concrete,
} asphalt, bitumen sprayed seal and block (segmental) pavers. Driveways
} serving from one to three residences can be designed as light pavements
} whereas driveways for multiple unit sites which serve four or more units
} are considered medium. Note that the quality criterion for pavers is
} minimum breaking load. For all driveways designed to use segmental pavers,
} the Medium Traffic criteria should be used for paver selection. This
} specifies a minimum breaking load of 5kN. Concrete pavements for domestic
} driveways should be a minimum of 100mm thick Grade 32 concrete on a 75mm
} layer of compacted sub-base. For other residential driveways, the minimum
} Grade 32 concrete thickness that will be accepted is 150 mm reinforced
} with F82 mesh at 50mm top cover.

That said, even 50-70mm of concrete with some mesh in it should be OK for
casual use, just don't be surprised if it eventually starts to crack. The
guy down the street put down a foot of blue-metal and 6" of concrete with
two layers of mesh so he could park his truck and not worry about cracks.

Oh, and buying cement and getting sand/aggregate from somewhere like a
landscape place will probably be much cheaper than pre-mix, and will let
you make a much stronger mix.

Overkill.

Post by Akhil Shastri
As added security I liked John_H's idea of putting some 10mm thick steel
plates under the stands to spread the load a bit.
Would this type of setup be more adequate?

Using a plate of some sort is the normal approach:
http://www.overlander.com.au/pg/equipment.php?id=23

Most of the solutions suggested will probably work OK, we're just being
paranoid since there's no way of knowing how clueful you are.

Antti

[Toby Ponsenby]

Post by Antti
Most of the solutions suggested will probably work OK, we're just being
paranoid since there's no way of knowing how clueful you are.

Ripper...been wondering what the opposite of clueless was.

Still waiting for the antonym of disgruntled, though.

[Clockmeister]

Post by Akhil Shastri
Ok, I just wanted to get some thoughts on this from people who might have
had a bit of experience with it, I know its unsafe to plonk the jacks
directly onto the grass.
Suppose the grass is flat and you were to use a fairly thick and wide piece
of wood under the jacks/axle stands with chocks on the unraised wheels.
Would this be a safe way to do it? Are there other materials you can use
under the stands(bricks, slabs of concrete?) to make jacking the car up on
grass safe?
I have an area in my backyard that is concreted, but it is only really wide
enough to jack up one side of the car on, so one side would be on the
concrete and the other would have to be on grass.

If you need to ask, it isn't safe. Don't do it.

[Dee]

Post by Clockmeister
If you need to ask, it isn't safe. Don't do it.

you twit ....

he's better off asking and getting advice than doing the wrong thing.
guess you never need advice for anything.

[Clockmeister]

Post by Dee

Post by Clockmeister
If you need to ask, it isn't safe. Don't do it.

you twit ....
he's better off asking and getting advice than doing the wrong thing.
guess you never need advice for anything.

1. You are not the one crawling underneath the car
2. You can't assess how dangerous that particular situation is from behind a
keyboard
3. Since you know a bit about what it is like to drop a car on yourself I
can only assume that you didn't learn from the experience since you don't
agree with my original comment. You may heve been young and stupid then, now
you're just stupid.

[Rainbow Warrior]

Post by Clockmeister

Post by Dee

Post by Clockmeister
If you need to ask, it isn't safe. Don't do it.

you twit ....
he's better off asking and getting advice than doing the wrong thing.
guess you never need advice for anything.

1. You are not the one crawling underneath the car
2. You can't assess how dangerous that particular situation is from behind a
keyboard
3. Since you know a bit about what it is like to drop a car on yourself I
can only assume that you didn't learn from the experience since you don't
agree with my original comment. You may heve been young and stupid then, now
you're just stupid.

To learn anything there's the hard way and option 2 asking the question.

[Clockmeister]

Post by Rainbow Warrior

Post by Clockmeister

Post by Dee

Post by Clockmeister
If you need to ask, it isn't safe. Don't do it.

you twit ....
he's better off asking and getting advice than doing the wrong thing.
guess you never need advice for anything.

1. You are not the one crawling underneath the car
2. You can't assess how dangerous that particular situation is from

behind

Post by Rainbow Warrior
a

Post by Clockmeister
keyboard
3. Since you know a bit about what it is like to drop a car on yourself I
can only assume that you didn't learn from the experience since you don't
agree with my original comment. You may heve been young and stupid then,

now

Post by Clockmeister
you're just stupid.

To learn anything there's the hard way and option 2 asking the question.

See #2

[Rainbow Warrior]

Post by Clockmeister

Post by Rainbow Warrior

Post by Clockmeister

Post by Dee

Post by Clockmeister
If you need to ask, it isn't safe. Don't do it.

you twit ....
he's better off asking and getting advice than doing the wrong thing.
guess you never need advice for anything.

1. You are not the one crawling underneath the car
2. You can't assess how dangerous that particular situation is from

behind

Post by Rainbow Warrior
a

Post by Clockmeister
keyboard
3. Since you know a bit about what it is like to drop a car on

yourself

Post by Clockmeister
I

Post by Rainbow Warrior

Post by Clockmeister
can only assume that you didn't learn from the experience since you

don't

Post by Rainbow Warrior

Post by Clockmeister
agree with my original comment. You may heve been young and stupid then,

now

Post by Clockmeister
you're just stupid.

To learn anything there's the hard way and option 2 asking the question.

See #2

Maybe but you can give him some hints on what not to do.

[Clockmeister]

Post by sheik yerbouti

Post by Clockmeister

Post by Rainbow Warrior

Post by Clockmeister

Post by Dee

Post by Clockmeister
If you need to ask, it isn't safe. Don't do it.

you twit ....
he's better off asking and getting advice than doing the wrong

thing.

Post by Clockmeister

Post by Rainbow Warrior

Post by Clockmeister

Post by Dee
guess you never need advice for anything.

1. You are not the one crawling underneath the car
2. You can't assess how dangerous that particular situation is from

behind

Post by Rainbow Warrior
a

Post by Clockmeister
keyboard
3. Since you know a bit about what it is like to drop a car on

yourself

Post by Clockmeister
I

Post by Rainbow Warrior

Post by Clockmeister
can only assume that you didn't learn from the experience since you

don't

Post by Rainbow Warrior

Post by Clockmeister
agree with my original comment. You may heve been young and stupid

then,

Post by Clockmeister

Post by Rainbow Warrior
now

Post by Clockmeister
you're just stupid.

To learn anything there's the hard way and option 2 asking the question.

See #2

Maybe but you can give him some hints on what not to do.

Maybe, but I offered advice that I know *definitely* won't get him squashed
;-)