A floor jack's STEEL WHEELS

Steel wheels aren't as robust as one might suppose. The 3.5-ton
Michelin floor jack's steel wheels laid down a thin layer of
a white, chalk-like substance which I can only suppose was
ground steel extracted from the wheels by the heavy weight of
the car as the jack rolled forward on the concrete ground while
lifting the car.

The substance looked a little like chalk scrawled on
a concrete street.

I think next time I'll lay a thin piece of wood or particle
board down on the floor for the jack to roll forward on as it
lifts the car.

Using a wooden runway probably isn't keeping with the rules of
floor jack operation, but I want the steel wheels to last.

Built_Well wrote:
> Steel wheels aren't as robust as one might suppose. The 3.5-ton
> Michelin floor jack's steel wheels laid down a thin layer of
> a white, chalk-like substance which I can only suppose was
> ground steel extracted from the wheels by the heavy weight of
> the car as the jack rolled forward on the concrete ground while
> lifting the car.
>
> The substance looked a little like chalk scrawled on
> a concrete street.
>
> I think next time I'll lay a thin piece of wood or particle
> board down on the floor for the jack to roll forward on as it
> lifts the car.
>
> Using a wooden runway probably isn't keeping with the rules of
> floor jack operation, but I want the steel wheels to last.
It's the portland cement in the concrete on the surface that is being
damaged, not the steel wheels.

You can take a metal punch or chisel and scrape it on cement to observe
the same on a smaller scale.

On a larger scale it does the same when you drive a dozer on concrete.
The tracks scrape the surface quite badly leaving the white marks,
especially when turning.

Your thought to protect it is a good plan. I don't have to do it often
but I use sheets of particle board when working on tracked equipment
rolling on a concrete floor that is six inches thick and reinforced. A
couple of times can ruin the boards but the floor surface is saved for
the most part. Even a small Cat dozer can weigh twelve tons.

>...chalk-like substance which I can only suppose was ground steel extracted from the wheels<

It's not steel from the wheels. Its concrete dust/marks in the
concrete from the weight on the steel wheels. That's usually a sign of
a weak mix or old concrete. We always called a weak mix a "barn yard"
mix, meaning there wasn't as much "cement" in the mix, which made it
weaker/cheaper, but was fine for a barn yard pour. Not allot of weight
going to be on it. Was manly for ease of cleaning the barn yard.

Ph@tBoy wrote:
>
> It's the portland cement in the concrete on the surface that
> is being damaged, not the steel wheels.
========

That's great news! Better the parking garage's concrete floor
than the Michelin's wheels :-)

I love this floor jack but it's a bear to lug around: 90 pounds
to lift it in and out of the car's trunk. (My apartment
building's contract doesn't allow working on the car in the
building's parking lot :-(

It wouldn't be so bad lifting up the jack, but there isn't a
good place to grip it near the casters. Plus during
the summer, I usually stop weight-lifting and begin running,
so my biceps and triceps aren't what they were 6 months ago
when I last lifted the jack. It was easy to lift then,
but much harder now.

If you need a good, reliable floor jack, Sam's Club is
selling the Michelin for $65--best cheap one I've seen
anywhere.

On Sat, 21 Jun 2008 08:07:40 -0400, "Ph@Boy" > wrote:

>Built_Well wrote:
>> Steel wheels aren't as robust as one might suppose. The 3.5-ton
>> Michelin floor jack's steel wheels laid down a thin layer of
>> a white, chalk-like substance which I can only suppose was
>> ground steel extracted from the wheels by the heavy weight of
>> the car as the jack rolled forward on the concrete ground while
>> lifting the car.
>>
>> The substance looked a little like chalk scrawled on
>> a concrete street.
>>
>> I think next time I'll lay a thin piece of wood or particle
>> board down on the floor for the jack to roll forward on as it
>> lifts the car.
>>
>> Using a wooden runway probably isn't keeping with the rules of
>> floor jack operation, but I want the steel wheels to last.
>It's the portland cement in the concrete on the surface that is being
>damaged, not the steel wheels.
>
>You can take a metal punch or chisel and scrape it on cement to observe
>the same on a smaller scale.
>
>On a larger scale it does the same when you drive a dozer on concrete.
>The tracks scrape the surface quite badly leaving the white marks,
>especially when turning.
>
>Your thought to protect it is a good plan. I don't have to do it often
>but I use sheets of particle board when working on tracked equipment
>rolling on a concrete floor that is six inches thick and reinforced. A
>couple of times can ruin the boards but the floor surface is saved for
>the most part. Even a small Cat dozer can weigh twelve tons.

Trying to protect the concrete is an unsafe idea. The reason why
these jacks use steel wheels is so they will roll easily on concrete.
When you jack up a car, the jack has to move to compensate for the
shifting lift saddle. Placing a piece of wood under the jack's wheels
will increase the friction to the point where it's moving, or trying
to move, the car instead of the jack. You could end up with a very
unstable lift that could damage the jack, the car or you. Although
the powder is very noticeable, brush it away and try to feel any
groove the wheels have cut in the concrete. You won't be able to find
any, it really doesn't do any great amount of damage to the concrete.

Jack

On Sat, 21 Jun 2008 05:17:33 -0700 (PDT), idbwill >
wrote:

>>...chalk-like substance which I can only suppose was ground steel extracted from the wheels<
>
>It's not steel from the wheels. Its concrete dust/marks in the
>concrete from the weight on the steel wheels. That's usually a sign of
>a weak mix or old concrete. We always called a weak mix a "barn yard"
>mix, meaning there wasn't as much "cement" in the mix, which made it
>weaker/cheaper, but was fine for a barn yard pour. Not allot of weight
>going to be on it. Was manly for ease of cleaning the barn yard.

Have you ever seen any figures on the amount of stress a hoofed animal
places on concrete. Believe me when I say that a 1000 pound cow will
stress a concrete floor more than a 4 ton tractor.

No one wants to put down a concrete floor more than once. So the mix
isn't short on Portland cement on purpose. The amount of money saved
is not very great and the durability of the finished floor is much
reduced.

Your "barn yard mix" comes from the fact that most of these older
concrete floors were mixed in a small batch mixer. You measured the
amount of sand, gravel and cement by the shovel full, not weight. The
amount of water is measured by eye and supplied by a garden hose. So
the proportions are an estimate at best. Add that to the fact that
these floors have been subjected to 75 to 100 years of acid leaching
by animal urine and fecal matter and you have concrete that isn't at
it's best.

Jack

Well, I guess if wood or particle board might hamper the forward
movement of the jack, perhaps because of a warp in the board, how
about just laying a piece of double-corrugated cardboard down?

"Built_Well" > wrote in message
...
>
> Well, I guess if wood or particle board might hamper the forward
> movement of the jack, perhaps because of a warp in the board, how
> about just laying a piece of double-corrugated cardboard down?

As several others have pointed out, the white marks are from the concrete,
not the jack's wheels.

Concrete is the most stable surface for using a rolling floor jack, and
putting anything under the jack would reduce the stability. I have been
using a rolling jack for 40 years and still cannot see any permanent visible
marks on any of my garage floors. Since you are not working in your own
garage anyway, I'd skip the cardboard, particle board, steel plates, or
anything else and just sweep the dust away when done.
--

Ray O
(correct punctuation to reply)

Built_Well > wrote in article
>...
>
--best cheap one I've seen
> anywhere.
>

Now, THERE's a classic oxymoron.......

Ray O wrote:
> "Built_Well" > wrote in message
> ...
>> Well, I guess if wood or particle board might hamper the forward
>> movement of the jack, perhaps because of a warp in the board, how
>> about just laying a piece of double-corrugated cardboard down?
>
> As several others have pointed out, the white marks are from the concrete,
> not the jack's wheels.
>
> Concrete is the most stable surface for using a rolling floor jack, and
> putting anything under the jack would reduce the stability. I have been
> using a rolling jack for 40 years and still cannot see any permanent visible
> marks on any of my garage floors. Since you are not working in your own
> garage anyway, I'd skip the cardboard, particle board, steel plates, or
> anything else and just sweep the dust away when done.
And I'm wondering if you leave the jack in the trunk all the time? If
so what about the extra amount of gasoline used hauling a 90lb jack
around in the trunk. The auto manufactures spend millions getting 90lb
off the weight of a car.