My DIY solenoid does not work
There are a few things I can see that might be the problem:

The magnetic field is strongest "inside" the solenoid, and it quickly fall off outside the solenoid. hyperphysics image of solenoid magnetic field:


However, this image ignores the fact that your steel core extends beyond the wire turns. Good conductors tend to prevent the "diffusion" of magnetic fields into them, thus the theoretical strongest magnetic field locations outside the solenoid is at the two ends of the steel cylinder.

The second issue is with how weak this electromagnet is.

Using this solenoid calculator, I found that for ~3.43A through your solenoid (theoretical current for a perfect 1.5V source and your given dimensions) the magnetic field strength was 35.9 mT. If I took into account the internal resistance of the battery (~0.15 ohms), the current reduces to 2.55A, with a corresponding magnetic field of 26.7 mT. This is only a few times stronger than a fridge magnet. Note that this is the magnetic field inside the solenoid. The magnetic field outside will be weaker.

Another caveat is I calculated these magnetic fields assuming the steel core was the same size as the portion wrapped with wires. It's not. It isn't immediately clear to me which length to use for calculating the magnetic field strength, So I simply used the length of the wrapped portion. The true length will probably be somewhere in between, so the magnetic field strength will be lower still.