Need Help!- Lead Screw info

[Drools]

I was given 2 different lead screws, I guess they were just kicking around at my buddy’s house. I have already purchased my Acme 1/2-10 lead screws for my build. I just want to know what these lead screws are, one looks to have 8 starts and 8 threads over 1 inch, is that possible or am I just not doing this right.
1/2"-8 x 15.5", 8 threads per inch, and the Delrin nut moves 1 inch per turn.
3/8"-9 x 12" very coarse 6 threads per inch. The Delrin nut moves 1.5 inch per turn.

I'm not sure where these items came from and what I could use them for in my built. They both have machined ends down to 1/4 inch with bearings. Maybe I could use the 1/2-8 for a Z-axis but what kind of stepper motor would I need to drive one of these?

[BobF]

I know this is not what you want to hear but "it depends". It all depends on a lot of things.The 1/2"-8 sounds like an 8 start Acme. It could run a Z-axis, but this is not where you need speed. It would probably work depending on the motors you choose and the weight it needs to lift. The other could also run a Z-axis.
Neither one looks to be long enough for X oR Y axis on any but a very small machine.
If your descriptions are correct they are both multistart screws.
The 1/2"-8 8 start screw is one that mcmaster sells, the other is not listed, and I don't know who might sell one like it.