OEM Customized wholesale Brass Copper Set Screw Cup Point Grub Screws for Indonesia Importers

https://www.cncmachingparts.com/
Jiesheng Hardware located in QiaotouTown Dongguan city Guangdong Province, now we has all kinds of imported machines, CNC computer lathe , computer processing center, precision automatic lathe, screw machines.

If you would like more information such as parts and pictures, go to the following address to download:

https://dl.dropbox.com/u/32737591/Attic%20Lift%20with%20safety%20device.pdf

Rotated Video: https://www.youtube.com/watch?v=i1Mkd7XmEO8

The floor measures 36″ x 54″. The hoist is rated for 650 lbs in a single cable configuration. I’ve tested it with 400 lbs of cargo with no problem. The spring that you see is to keep tension on the hoist cable to keep it from unspooling, and at the same time lets you set the lift solidly on the floor. There is a micro-switch at the top to automatically stop the lift. The first time the lift stops at the top, it is at floor level, then you can flip a hinged piece out of the way, and the lift automatically stops at the “save your back” height. The 5 gallon bucket is full of large bolts to act as a counter-weight to effectively eliminate the weight of the wooden lift itself from the work of the hoist. With a ceiling height of 12′, the total lift rails measure 19′ which puts the floor of the lift at a maximum 15′. There are momentary up/down switches at the top, bottom and on the lift itself. The rails were designed for sliding barn doors (20′ cut down to 19′) and the lift rides on 3 sets of barn door trolleys designed to hold 400 lbs of door per set, and two rubber wheels at the back bottom that relieve almost all of the pressure of the bottom trolleys in addition to giving a smoother ride. The pulleys are rated at 3000 lbs and roll on ball-bearings and are held by 5/8″ bolts which go through 5″ of wood.

I’ve got a regular walk up stairway, but this sure makes it easier to move stuff to and from attic storage. As you can see in the pictures, the decking is not quite complete. There is a back-board that I left off for picture taking purposes. The last thing that I need to do is design a safety feature that stops the lift if the hoist or a cable fails. Otherwise, everything else is way over-engineered to prevent any future problems

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9/8/2011 I’ve received a lot of requests for more information on this lift. I don’t actually have measured plans at this time, but I have a bunch of pictures and some more information on the components. If you’re interested, send me a note with your actual email address and I will forward what I have. Take care, Tim
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Questions and Answers ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

1) What is the purpose of the rabbit/notch in the 2×4 where the barn door wheels are mounted? Is that just to bring the wheel body closer to the frame (so the “hinge” where the bolt connects to the wheel body sits “inside” the 2×4 instead of pushing the cart an additional 1/2″ away from the wall?

- The notch is simply to keep the roller assembly from twisting. This normally wouldn’t be a problem unless you inadvertently put more weight on one side causing the lift to naturally want to go up cocked. With the wheels locked up and down, it tends to keep the lift more stable and level no matter how you load it up. The lift isn’t going to twist too much because of the track, even with the other type of roller assembly, but I imagine you’d get significantly more binding and friction as it moves up and down. It does add the extra 1/2″ of stand-out as you mentioned also.

2) What brand of barn door track / wheels did you use? Is it the ones made by Stanley? Yours looks different than Stanley…

- The rollers are made by Stanley, and I bought them from Tractor Supply. I liked this model because the connection did allow for a stand-off and kept the assembly from twisting as described above:

https://www.tractorsupply.com/national-hardware-reg-5040-flexible-hanger-zinc-3551929

- The tracks can be obtained from a Stanley dealer as well. The Tractor Supply that I went to had a max length of 12′. I needed 19′ for each track, and I wanted a single piece, so I went to a local metal building supplier (Mueller) and bought two 20′ sections for about the same price as Tractor Supply’s 12′ sections. They weren’t made by Stanley but had the same dimensions.

3) For the hoist, you used this one from Harbor Freight, right?

https://www.harborfreight.com/880-lb-electric-hoist-44006.html

- For the hoist, I used the 1300 lb model (depends how much you want to lift, but, the beefier, the better). Note that the hoist is really only rated at half it’s depicted capacity. They get away with saying this is a 1300 lb hoist by doubling the cable through the use of a pulley. You can actually use the hoist in that configuration, but remember that it also halves the speed of the lift travel:

https://www.harborfreight.com/1300-lb-capacity-electric-hoist-2954.html