@endlessfix, I was trying to remember how the bifold hanger doors were popped out when the over center locks were released. Is it just a cable tension thing?
It’s been 20 years since I had to get a plane out of a hangar.
There are two methods of overcoming the initial angle that I can remember now, there may be more. One is to mount the lifting point far out the center of gravity of the lower door so that it can apply some tiling force at the start. The other is to use standoff bars on the backs of the doors that deflect the lift lines when closed. When the lift lines come into tension at first lift they also bear against the bars to apply outward force at the center door hinge to start the doors moving outward.
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Ah, yes. Thank you I remember now that the hangar doors at the airport I flew out of had the cables set up like your second example. As I recall, the guy who owned the FBO made the over-center locks for all the hangars himself.
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Ha, I had to look up FBO. Clearly the only flying I ever do is with a drink in my hand, I just happen to know something about doors.
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Wow! Thank you for that!
The goal is to set these into the brick window openings, rather than bolted to the face of the brick exterior. The channels will be set to each side of the brick vertical surfaces and attached. When the shutters close, the steel plates will be essentially flush against the channels ans flush with the brick surface.
In order for the whole thing to fit into the space around the window which is basically one brick deep, the wheels would need to be centered at the sides of the lower segment, so the two panels lay flush against the channels when closed.
Also, it seems you have provided a header for the actuator. The actuator will be mounted to the inside of the two panels between the steel shutter and the glass window, which is why there are grooves to give space for them to extend through the hinge pivot point.
I would love to do a simple cable lift from the sides, or some cable or strap lift as in your illustrations, but there isn’t enough room there. I only have the width of one brick to function in, and that is only 2-7/8" of width. Also, straps do not resist manual lifting of the lower panel, but a linear actuator would be a solid link that would prevent the shield from being forced open.
Here are some photos for your amusement and consideration!
Joe
For this one particular window, I see an issue with head clearance at the door when the cover is open. I may need to do something different with this one.
If I mount them to close against the brick on each side, I suppose I could have the bottom wheels roll nearly to the top of the inset, with the rest of it mounted to the brick above the window.
Or, I could alter the lengths of the two panels so the open geometry raises the fulcrum higher up.
I will play with some designs …
Are you planning a similar shutter over the door? If so, how do you plan to deal with the interference between the shutter on the door and the one on the window? Have you considered using roll up metal shades instead?
Hi Dave,
The door in the photo will have a large, decorative wooden barn door on a rail that slides to one side. There is plenty of room to the left for such a feature. Closing it would be simple with a single actuator and a cable with some pulleys to multiply the stroke.
The front door is inset on a brick porch, so it too will be secured by a different process.
Joe
If I could find a gear box powerful enough to raise the shields, I would just put a gear on the top hinge/shaft and rotate it 90 degrees, but I fear a motor that powerful would be HUGE.
Joe
For your entertainment, here is a tilt bed flatbed I designed and built from scratch, using a compass and a protractor! After I sawed the truck into two pieces while still owing $20,000.00 on it, I thought, “I sure HOPE I can pull this off!” Otherwise, when they repossess it, I’d say, “The front half is over here, and the rear half is over there!”
Joe
As I look at this more closely, I believe I may have to abandon the sleek, sexy flush mount design and go for something that lays over the brick instead. I was trying to stay away from HUGE, but mounting the shields to the exterior brick surface will give me more room for the mechanics behind it, between the shields and the glass window.
For the moment, I am still going to try for a flush system. That will prevent, or at least resist crowbars and other things better than something that can be pried open, using the bricks as backing.
Joe
Joe
Is it important that they tilt up? If t he covers were one piece and side hinged they would be self supporting and the actuation force would be much less as the hinge would support the weight of the door. They could fit inside and maybe open flush with the wall, 180 from the closed position.
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I thought about making two side shutters that close and lock, but I am trying to kill two birds with one stone; that of securing/protecting the glass windows in a tornado, and providing shade from the hot Kentucky summer sun against the windows. I thought a canopy would do, but I don’t want to get canvas canopies, which are bird %^&* magnets that deteriorate over time. They also do not hold up in these strong Kentucky wind storms.
I considered making hanging brackets, and simply tugging out a small trailer behind my riding mower when a storm approaches, circling the house and simply hanging guards over the mounts embedded into the brick, but that does not address the issue of my not being here when the tornadoes come.
I have played with many different ideas, and this one (the fold up steel guards) seems the most logical. They can be easily cleaned with a pressure washer, and deployed when needed, to protect the windows in less than a minute, even from a remote location. Meanwhile, they provide shade from the sun, and can even be used AS shades by manually lowering them (n%) when needed.
Two cables on the sides is the easiest solution, but then I have nothing at the top to reel them in when needed. Also, cables do not lock the shields into a closed position like a linear actuator would, so an additional locking mechanism would need to be added.
Joe
See, now you are beyond my current understanding of SketchUp. I wish I knew how to do all of that magic you speak of!
Rather than seeking the throw distance, the actuators I have found (online) have predetermined throws of 6, 8, 10,12,14 and 16". So I am not sure how to reverse engineer it to fit an actuator to arcs and lines. I was hoping to fit the apparatus to a specific stroke length, both open and closed. Am I doing it half-as*ed and pie-balled? I am not an engineer, and I do not play one on TV. 
Joe
I suppose I could just work out a simple V with a known open and closed stroke distance, and then decide where the two mount points are located in relation to the center hinge. After that, it should not matter if the panels are longer on one end, or both, right? Wouldn’t the panels fold the same, regardless of their lengths?
Joe
There is another program I recently encountered. I am trying to learn it now. Here is a short video I made of my first foray into LINKAGE.
and … it is FREE!!!
Joe
IMHO, I don’t think you have room for a lineal actuator on the inside.
I know it’s not aesthetic, but this would work.
Not so. Check out the parts dept at your local RV dealer. Slide-out motor with reduction gearbox can fit in both hands. (The motor is about 4 inches in dia., maybe 8" long.)
Ummm … thank you for the suggestion, but the whole point of this is to
- Learn SketchUp
- Design and build my own storm/burglar shields
3.Do SOMETHING with my workshop and tools!
Yes, I could easily whip out a credit card and sip sweet tea while the workers install my store bought shutters, but what fun is there in that?! Besides, roll down windows require some sort of box, somewhere, for the roll when the cover is retracted. This is a wood frame house with a brick facade around the exterior. I would either need big boxes over the windows (granted, not much different than metal wedges 
) or have something INSIDE of the house over each window to provide for an exterior roll down cover. The COST of those store bought units isn’t cheap either. They are VERY proud of their products, and their prices reflect that fact.
I have been playing with the design on and off all day long. I did like the other submission by Endlessfix. It occurs to me that if I mount them to the brick above the windows, and let the shields lay against the bricks rather than try to fit them inside of the window frames, I can have room for the actuators, and the bottom of the lower panel would retract nearly to the top of the window, minimizing obstruction of the view from the inside. I would just need to make the panels a little longer, and a little wider. I have a 5x10 plasma table, so that is not a problem.
I will draw up the mod and submit it here, for you SketchUp experts to examine.
Joe
They were meant as suggested concepts.