Hello forumers

I live on the fourth and last floor of a building. There i have my hobby room. On one side of the building there is an empty space. I want from this side to make an elevator (not for people of course) to elevate heavy things for my projects. Not more than 100 kilos.

I would not go into more details for this crane as i think are not important but if you want i can analyse you all the construction.

The thing is that i want to choose drum and motor. I already have a torque converter that will reduve the input rpm with a ratio of 1/30 (approximately).

Here are my calculations:

I want to have a lifting speed about 20 meters per minute (the carriage will make about 30 sec to come to the 3rd floor).

The motor i will choose may have 1500 or 3000 rpm. Suppose i get the one with the 1500rpm

After the torque converter the rpm will be 50rpm

In order to get a speed of 20mt//min, the drum must be calculated:

Every minute we have 50 turns, so every 50 turns there must be 20 meters. This means that every turn of the drum, it must pull 20/50 = 0,4 meters. The peripherial of the drum must be 0.4 meters. This means that the diameter of it must be:

per=pi * Diam = > Diam = per/pi = 127.38cm. The drum must be about 130cm diameter.

Up to here i can handle. Now what should be the power of the motor to lift with this drum 100 kilos?

Any help will be apreciated

Thank you