Counterweights for a Folding Door

Thoughts on how to balance the weight of a heavy folding door with vertical action. October 2, 2010

Question
Is there any type of hardware designed for the function of this type of thing?


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Forum Responses
(WOODnetWORK)
From contributor S:
I don't know, but looks like some Soss hinges would work for this. A channel on each end for a roller, perhaps.



From the original questioner:
They are Soss hinges, but I'm trying to find something that counterbalances the weight of the door when it's lifted, as well as holds it up out of the way.


From contributor S:
Just an idea - may work, may not. I remember the old window sashes that used hidden counterweights attached with ropes and pulleys. This might work if you can hide them behind the channel. The problem is, once it's locked in the vertical position, it would have to be pulled to unlock and allow the bottom to slide up. Then there is a problem of it slamming into the top because of the weight, unless you used a shock absorber of some sort.

Another idea is a spring attached, although could be dangerous if it broke. Nah, I wouldn't do that on second thought.



From contributor J:
I had the same idea when I first read this. If the counterweight is sized correctly it shouldn't slam; the panel should actually stay in any position between fully open or fully closed, just like a double hung window would. I don't know if there's any better hardware for this application, but I think the counterweights could work well.


From contributor S:
You're right, it's all about getting the weight balanced. I didn't think of that. I think if the weight is correct, there could be a handle mounted right in the middle of that thing. Pull on the handle and up goes the bottom.


From contributor D:
I have seen the counterweights made from both pot metal and lead. Lead might be the easiest to trim up to a correct weight. It should be as easy as weighing the total weight of the unit and dividing by 2. This should be the ~ weight of each counterweight. And if you can't find one, it shouldn't be too hard to make your own. Scrap lead is easy to come by. Find a fisherman who has a melting pot you can borrow. You should be able to make a quick mold that would stand up to a couple of castings. Drill a hole for the rope, trim the weight down. Should work just fine.