Building your own stair lift is no easy task. Do you know how to weld? Do you have a good understanding of electrical components and wiring? Those looking to save money on a stair lift are best off buying used. A good used stair lift can be found for half the retail price.
It seems that some are interested in building a stair lift for their dog or cat, while others enjoy the engineering challenge. I came across a very detailed plan for a homemade stair lift from a gentleman in the UK with a suggested build cost of 200 pounds ($320). The stair lift was built with metal rails and a winch. Although it appears to be functional there are a number of safety and legal questions that come to mind.
A link to the original build details is below. As noted in the details, you will need an arc welder to construct the frames and rails. All of the other components appear to be fairly accessible and easy to assemble.
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