Unlike some hoist builds in garages, I did not have the luxury of lots of space for block and tackle, counterweights and big motor. Everything was going to be tight.
Getting this thing to up and down evolved many times over the course of a year as more and more weight came into play.
My original concept evolved around a garage compression coil lift and a jack shaft operator. I had no vision of needing counter weights because the coil would add the additional lift.
I sized the coil for my anticipated calculated weight plus a few pounds and ordered accordingly. There are some key mechanical logic reasons that made this not work out,
but in the end my final weight is probably double what I estimated back then.
While the frame and wood was only about 80# all worked fine, but as more was added, things did not go as smooth.
The big mechanical issue was my not seeing that on a typical garage door coil, you reduce the load on the coil as the sectional door goes from vertical to horizontal.
So as the coil unwinds, its lifting capacity goes down along with the amount of force it needs to exert to move the door. In my build, the load never changed. So as one would imagine, the heavier the track got, the farther from the ceiling the platform would be when the lifting capacity stopped.
It was time to abandon the spring and go to counter weights. This additional torque played havoc with the end mounted motor, so that got relocated to the center of the shaft.
There was a lot of up and down and taking apart and redoing. All this while I continued to finish the space. But at some point I eventually got here.
They are not shown here, but that was the beginning of the final operator that has two stacks of lead counter weights connected to cables that are coiled in reverse of the cables that raise and lower the track platform.
In its current operating condition, there is probably 160# all going up and down within the stud wall cavity. The operator, a belt drive ZAP Lift is also within the wall and the shaft is just outside the studs on multiple pillow blocks.
Below is an in-process shot of the final cable pulley system, larger radius pulleys on shafts set with axel bearings at each end. The goal was to minimize friction as much as possible.