Have not had a chance to get pictures but here are some specs:
Actuators - 1000lb push / 800 lbs pull each. They are switched on and off together, however, when top extends or retracts, each will continue until their independent limit switch is reached. This "re-synchs" them each time the top is fully raised or lowered. The switch is manual and is set up as momentary, requires one to activate the motion. US based company supplies them, readily available.
Raise or lower time is about 80 to 90 secs.
The top with the hardware that is attached to the top - actuators, tracks and lifting bars, insulation weighs about 240 to 250 lbs. The fiberglass shell by itself can be picked up by two strong people and placed on the roof, so I am guessing it weighs about 170 ish. The metal frame it sits on, along with the actuators makes up the weight difference.
The lifting assemblies at each end are made up of 1.75" diameter tubes with 1" diam tubes welded to them. There are caps on the tubes so I could not measure the wall thickness accurately, but the 1" tubes look to be either 3/32 or 1/8" wall. The actuators connect to roller assys that ride in 1-5/8" uni-strut solid channels that run, on each side, nearly the full length of the top. The lower frame assy is ~ 2" angle that runs the perimeter of the top cut out. Maybe shenrie can get the pics of the shoulder bolts used as pivot points.
Failure modes - If the top is all the way up and one motor fails, take as much load off the failed actuator side and remove one or both of the clevis pins and use the good actuator to help lower the top. I would likely want some type of stick to help take the load off the failed actuator and help the top come down somewhat evenly, but the top can be brought down and then secured. The lifting struts remain attached to the uni-strut channel front and rear to guide it into position.
If both actuators fail mechanically, this would require disconnecting both actuators and manually supporting the weight of the top to guide it down into the lowered position. If electrical switch fails, one could use a drill battery to raise or lower the top and bypass the relay and/or switch. There is a manual wired switch as well as a remote control switch.
I can take pics later this week if shenrie gets tied up.
This youtube link is pretty good at showing the operation of the tops, there are also shots of the lifting mechanisms in motion:
Interested in feedback as to what you guys think. All in all seems stoutly constructed, but I am not an engineer