Homemade greenhouse door opener

Today was just beautiful, and while not playing with Jude and her frisbee - I was able to work on the automatic greenhouse door opener a little bit. A defective printer at work was disassembled for the carriage drive motor and shaft - in hopes that the little motor would be able to somehow crack the door to allow cold winter air in to to cool things off on a sunny day. The fact that it ran off of 5 volts dc was definitely a plus, especially since it will be located at least 100 feet from the nearest power source on the property. (And I have several 12 volt batteries laying around)

Anyway, the assembly was mounted in the top right corner of the door frame -which is opposite the hinged side......It looked like a good place as any, and was completely out of the way for accessing the plants later.

Photo below - here's the entire assembly in place, with the end of the driven shaft supported by a special pvc clamp that was purchased from the freaky merchandise store by my work. A hole large enough for the shaft to protrude through was drilled into the clamp, then the clamp was fastened to the vertical piece of pvc pipe.

Photo below - here's a closeup of the little support, and notice that the hole had to be drilled off-center...this was done so that the alignment between shaft and the door of the greenhouse would be parallel to each other. I got 47 of these special little pvc clamps for 3 dollars, and will get alot of use from them..

Photo below - these closet pole sockets were only 50 cents at the merchandise store, and I just had to figure out a way to incorporate one of them into this design. So, a dremel tool with cutting disc was used to remove the flat part of one, and a hole just larger than the end of the shaft drilled into a strategic location on it.

Photo below - it was then mounted onto the splined shaft, and trimmed so that as it wouldn't bind against the vertical piece of pvc pipe as it was rotated. A dremel is really handy for situations as this, and getting the right curvature was pretty tricky...

Photo below - as the shaft is turned, it causes the offset piece of plastic to push the door open. A couple of pvc clamps and piece of pvc pipe are mounted to the door itself, which gives the plastic piece something curved to rotate against. Gosh I hope this makes sense, but will do a video if needed....

Phgoto below - here's a view of the entire thing, and of course Jude patiently waiting for me to get finished.

Photo below - since the little motor couldn't push the door open because of the tension of the spring, I installed another motor that was twice as big as the first one tried. All kinds of modifications were made to the support frame for the motor, and the little belt pulleys were switched, too....

Photos below - sequential pictures from an overhead view, showing how the door is opened as the shaft is turned. (And yes....i'm fully aware that socks don't go with crocs. Ha!) Oh yeah, the spring was replaced with a small rubber band. This worked alot better....

Photo below - cracking the door open this much should be plenty for ventilating  the greenhouse on a sunny winter day....

Photo below - spiderjohn wanted to know what kind of clamps will be used to fasten the plastic sheeting to the greenhouse frame later, and here's a closeup of one that was cut in half. What was 40, now is 80 of them. Oh yeah....the cut on my hand is from sticking a screwdriver in it while tightening something at work...No big deal.

These will be clamped over the pipes, then screws might be installed if needed for keeping it secured in place. It'll be skinned when the temperature gets in the mid-twenties, as most things out there right now are hardy down to that level.
Of course the little control system for it will need to be put together really soon, and the only thing i'm waiting on is a thermostat of some kind. Everything else is already on hand, and the little computer fan mounted into the top will probably be included, too. I'll do a post on the control system later.....

In other news, I have something wrong with my shoulder, and appears to either be a pinched nerve, or something similar. It hurts really bad, even when not being used. So, a trip to a specialist will be made on Monday morning, and we'll see what the diagnosis is. Wish me luck...

Take care, and happy gardening!

EG