I've seen plywood self destruct when inexperienced riggers used it while lifting heavy machines (many tons). It's important to avoid metal to metal contact (machine to fork truck) or the machine can slide out of control while being moved. Therefore wood gets used in between metal parts. But, IMHO, in this application plywood shouldn't be a problem unless it is laid on a very uneven surface or on a pressure point that can penetrate the surface.

 

Wow, glad you're OK and had the jackstsnds under there.

 

I just bought a quick jack - it actually just arrived today. Watching that video has me a little concerned over using those blocks. they certainly bend/deflect quite a bit on the initial lift. I could see how that could unsettle them when stacked.

 

Floor jacks and stands, period. No futher comment.

 

If you're a floor jacks and stands only guy, you should look into the jackpoint jackstands. They let you jack and support the car on stands from the same lifting point, which is genius.

Different tops for different applications. One is designed to work with both a pin setup like on a Porsches where the pin goes up into the jacking hole so the car can't slide off and this same top has a groove in it for compatibility with a seamed lift point. They also have a metal flat top, and the indented circle in it is the perfect size for the Rennline jacking supports that lock into the lift point holes. Additional flat tops can also be stacked as the rings interlock so they can't slide.

When I have to use a jackstands, this is my go to.



Here is a flat top with the additional height top that holds the pin and works on welded seams stacked together for a bit more height.






Floor jack goes up and down in the recess with the top on the jack pad and then that top.mates with the top of the jackpoint jackstand.

 

Those are pretty cool. They are bit spendy but a clever idea.

 

Man that's a proper garage!

 

If that was directed toward me, thanks. That's the tip of the iceberg

 

Fortunately I have never had a problem with Quick Jacks, but you can't leave anything to chance with them. Instructions must be followed exactly. That means proper air pressure in the cylinders and QJs perfectly parallel, centered under the car jack points, same distance from a point on the car, like front tires. A tape measure is required. Then the rubber blocks must be centered in the jack platform. Then the jack stands after the QJ is locked in place. I have lifted my wife's Lexus RX 350 with my 5k version, carefully. I think I may use AC 3/4" plywood pieces large enough to fit in the QJ, and then the rubber block, instead of two rubber blocks. I like the larger base idea.

I did hear of a guy who had a hose rupture and spray his garage and himself. Who knows if he kinked or pinched the hose.

 

I agree with all of this, and except for the tape measure part, I take my time and set it all up as perfectly as I can. However, the manufacturer needs to understand that the instructions are fine and all, but "in the field" nothing ever goes exactly to plan, time over time in a repeatable way. There has to be some allowance for deviation, or the product can be dangerous. In this case, it wasn't the jack that failed, but the double stacked blocks. They should remove that instruction before someone really takes one on the head. I posted this on the 928 forum too, and one of the guys there suffered a similar thing while lifting his daughter's VW with the double stacked blocks.

 

I would never double stock those blocks that come with QJ. If you don't want to buy SUV adapters and insist of double stocking block, get oversized block like I did for the bottom, then place 3" QJ block on top. QJ goes forward/up, not up/up. Things may shift much easier going forward/up

 

I agree, the double stacked rubber blocks should never be used. If the QJs are not perfectly parallel the load becomes even more unstable as it rises. It also puts additional stress on the jacks. That's why I use a tape measure.

 

I own a BL500SLX jack. I never use double stacked blocks provided by QuickJack. For lifting 977 single smaller rubber blocks are all that's needed.
I made my own blocks from solid aluminum to fit older E24 BMW. I make sure both frames are parallel and spaced equally under the car.
I always make sure to lower the jack onto the safety locks on the frame so the jack does not rely on cylinders only. Haven't had any issues.

 

Aluminum implies metal on metal contact which can be slippery and should never be done. I've said it before and I'll apologize for those who have read this before but ...

I was setting up a machinery show in Germany many years ago. A nearby fork truck operator who didn't know what he was doing picked up a machine without putting wood blocks between his metal forks and the metal machine. He lifted the machine. The machine slid on the forks and fell. A helper lost his arm at the shoulder.

Do not jack anything up with metal on metal. Use wood blocks if you want no give. Use rubber blocks if a bit of give will help lock the block into the jack or the jacking points.