prototyping solenoids

today using a very small spring generated the force i require to eventually move a key. i generated another concept of placing the spring at a different location to increase the 'push'. see diagram below...


this formula will help me calculate distances and make sure all the distances relate correctly.



i mocked up this prototype lever, as the force is fairly weak i made the model out of paper. the next step is attaching a mock key to the end of the lever.