Bottle jack/jack stand combo
 

I saw this while looking around for a trolley jack & jack stands
http://i1222.photobucket.com/albums/...standcombo.jpg

I look at that & I think of how I could modify a regular bottle jack & a regular jack stand to work like this.
I'd get a 3/8" plate drill & bolt it to the top of the jack stand (you don't want to weld, it'll weaken the casting of the jack stand) with a round cup on the underside where the top of the bottle jack would go. That way you can still use the screw extension on the bottle jack.
The jack side of the plate will do all the lifting & I haven't used a jack stand yet that doesn't automatically lock as you lift it up. Only difference here is the bottle jack would be doing the lifting & bring the stands top along for the ride. Weld a 1/8" plate under the jack stand so you have room for the bottle jack & maybe some little positioning plates to hold it in place. Then you have that as 1 unit for lifting & safely supporting in one piece!
:icon_couchhide:

Interesting concept but I don't know about how it looks like your suppose to set the frame in between jack & the J-stand. when you'll have to relax the jack to get the stand to lock in. just my .2
also if you do build one remember to match the lift max on both the jack & J-stand or not to go over the max load on the weakest of the 2. lol

Yeah after you raise it then lower it a little the jack stand will lock. To lower it all the way the lock flips & stays there so it will lower all the way.

if i had to buy a jack stand like that id stick to a regular jack =P

Same basic design as the railroad jack I use to jack my tractor up.

Only problem I see is price. I can buy 4 jack stands and one good floor jack cheaper than 4 cheap jackstands and 4 cheap bottle jacks. Also willing to bet I can store less in a smaller spot.

Neat idea and might work fine if you only needed one. I only use jackstands if I'm gonna be under the truck. For changing tires I just jack it up.