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Doors and WIndows Automation Answered


I am trying to automate the windows and doors in our barn using NEMA  stepper motor and Lead screw and would like to exert around 20 Kg force for opening or closing. The windows are fairly old and made of wrought Iron.

I am wondering if somebody can advise and help me selecting the motor (based on torque) and the appropriate diameter of the Lead screw for this instance.  The idea being that when the lead screw rotates, the ball nut flange moves left or right and pushes the connecting rod out or in thus opening or closing the window

I have attached a rough sketch what I had in mind and please pardon me for any mistakes.

Many Thanks



Sounds like a simple project for a linear actuator with one end fastened to the door frame and the other to the door. Linear actuators are available with a broad range of stroke lengths from 1" to 60" and force strength from 30 lbs to over 2,000 lbs. Suggest you Google linear actuators and you will be amazed at the incredible variety available that will easily solve your problem.

Please delete your other topic to avoid confusion and maybe get some more responses.
Patience is the key here ;)

A belt and pulley system like used for most CNC or 3D printing projects might be far easier to build.
And you can change the torque going to the mechanics as easy as changing to different sized pulleys.

Don't know your size limits but have you considered going scrap?
At the wreckers you can get motors for car seats dirt cheap if you don't mind taking them out yourself.
Running on 12V and with massive torque through their lead screw you won't need any complicated mechanis - just use them like a pneumatic piston ;)
Some even come with built in limit switches.
Bit of a pain to take apart and place in a new spot but these switches can be misused to set the open and close position for the window.
This way you only need to connect power to the right wires to make them open and close....