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I think the elevator I was talking about has a pit under it for the machinery.

Too subtle Dwight
Merely a comment about comparing dissimilar things regarding Rich's motorcycle/elevator analogy above

Sure Mark, I understand where you're coming from.

Retrofitting an existing lifting technology is what I'm thinking of. But, fella's, and with respect to Bill, I think my analogy holds. I Am one of those guys who have built bikes from scratch, two of them. And a couple of street rods. Frame up kinds of stuff. And I carefully study the mechanical ramifications of what I'm doing. And I ask lots of questions from people who know more than me. Perhaps my query was not strait forward enough. I've seen custom bikes on the net and in magazines that would never pass standards for braking, turning or highway speed driving. But there are plenty of people here who slobber all over them. It seems to me that a simple lift mechanism, applied from some other field to rise twenty feet in the air, would be much safer to contemplate than a machine whose collision force potentially reaches a maximum impact of 120 mph.

Your points are fair enough, Leno. However, I think that the idea of a pvc/air/hydralic bears some thought. Around here, teenagers are fond of "potato guns", made from 3 inch pvc tubes, and that is a lot of expanding power. Schedule 40 PVC pipes have 3/16 sidewalls and are seamless. I would suggest that for the weight and travel of this theoretical braking system, four 3 inch pipes on 4 corners with decompression holes at the bottom to let the air out of the ram, it might work to adequetly slow a falling platform of roughly 400 pounds down.You understand, again, I'm just brainstorming. (The four hundred pound figure comes from the weight of the platform, 200 pds, with a counterbalance, and two, 200 pound people.)

Good, honest advice, Clay. Thank you.

As an aside, I think you are confusing the slowing down method, and the safety brake method. They are seperate and distinct. One is used as a damper, the other is for when the everything including the damper FAILS.
The safety brake is a LOCK. You don't want to do that with PVC.
I have actually seen a design for an elevator using plastic tubing for the raising and lowering mechanism(pneumatics)

Clay

Astaren,
Just reading through this post, and have almost been down this road before with my stepdad. A couple of questions. IF you go with a winch system, will you be able to build a robust enough structure at the top of the "elevator shaft" that can distribute the weight properly to the supporting walls. I'm thinking, without doing a lot of calculations here, that you're going to have to build a pretty significant set of walls from normal construction grade lumber to support the weight of your maximum passenger load PLUS the elevator mechanism itself, not to mention the joist itself to be able to carry that load. That also probably means beefing up the foundation that is going to support this area of the house, since you'll have a narrowly concentrated area of weight instead of the weight being distributed along a foundation or kneewall or something along those lines. All doable of course, but definitely things to keep in mind. The manlift idea is probably pretty doable as well, but again, you would want to beef up the slab under this area, since a manlift is NOT light to start with, and if you're going to throw a platform onto it as well as 6-800 lbs of passengers that would be a lot. Also, with a manlift, give serious thought to ease of maintenance as well as safety while you're under there replacing a hydraulic unit, or greasing the various lubrication points. Also, you would need a way to even get the thing into place, whether it be driving it into place on the slab, building a concrete and steel platform for the manlift to be bolted to, as well as bracing it from all sides to eliminate the inevitable sway (maybe something along the lines of the type of railing used in garage doors running up the sides of the elevator shaft and meshing wheels into these shafts from each side to eliminate sway. The challenge with a manlift of course would be the controls, unless it was simply available to who was operating it at the time. No matter how I look at it, it sounds like a lot of work. When we were contemplating it, we actually had a working set of elevator controls and floor switches (to stop the elevator at each floor) from an old bank building, thankfully it never went further than the idea stage though. Whatever you do, good luck and be safe. If it were only for your personal use, it would be less of a concern, but if you put your family members on it, any mistakes made by you might be paid for by them, although I'm sure that has already crossed your mind.

RICH,
WAIT!!! I read you post and replied immediately, without reading any others. Elevators have serious safety concerns.
Elevator operations are WAY over the capacity of most mekanical injuneres. Ask for an elevator mechanic - preferably a union member (they are the best).
You're a wood butcher - you should know that.
The only elevator I'd build cheaply around the house is one I could jump off of. That way, you can see how bad it's gonna end up.
I'm done. Please feel free to hammer back at me.