Gdetrailer wrote:
I have been using a 3.5 ton floor jack for well over 30 yrs on a concrete floor to lift my pickup trucks. I have not once ever seen the wheels on that jack or trucks move even 1mm..
Seen, that is the issue. The fact that many people do not realize the jack wants to move points out to me there is a risk. The beauty of a floor jack is you roll it in place on hard surface, stroke it up to contact, check that it is right, then jack the vehicle up without watching it. You might be surprised if you marked at start.
That floor jack I have also has a contact point which looks like a castle and is 5" in diameter. Never had it offer to slide on that contact point either.
But when using the jack on a hard surface, like a concrete driveway, there is very little side force applied because the wheels roll. On the side of the road, wheels sunk into asphalt, there is a good chance of slip. (I have seen a little trolley jack lift it's rear wheels, wedged against bottom of car, when it rolled off 2X10)
I think you have a piece of junk floor jack if it moves that much distance, you need better floor jacks.
Not ALL floor jacks have a large arc swing, junky cheapos and 50 yr old ones perhaps but not all.
Well, my Walker is pretty old, but I have had several. All seam to work pretty much same way. I think how much the carriage moves could be calculated by somebody that paid attention in math class, knew length of arms, (Radius) and how much lift
You make a good point about only using part of the travel. This is best no matter what style of jack you use. That is why I suggest pulling the flat up ramp to get center of hub normal height before jacking. Little lift, pull ramp out, got all room needed
Floor jacks and even smaller cousin the trolley jack both have a large base foot print over a much greater area making them by far more stable and less likely to tip over provided you only use the absolute minimum lift needed.
Large contact area? Compared to what? All mine, even the 10 ton capacity I don't use anymore, each have 4 little bitty steel wheels that contact the floor. Now the contacts are spread out over a large area, are stable
on hard surface. But the wheels will sink into asphalt sooner than the same weight on even the smallest bottle jack. Yes, the carriage will bottom out, spread the load, but not stable.
