Poor mans jack

I went to the junk yard and got two identical screw jacks and welded them together end to end. The jacks where pretty reasonable. Here are pictures with some measurments.

Interesting idea.

How stable is it in the full raised position?

Thats an interesting question. I use it to stand the motorcycle up to check the oil and change the oil. I jack it up high enough to spin the tires and check air pressure but I never have took it to the highest level since I have a regular jack for that. I had it under the bike earlier today changing the oil and I wish I had jacked it up all the way to see but I didn't. Sorry.

Thanks

With the back wheel about 1 1/2" off the ground it feels about like having a bike on a center stand.