Adjustable Book Stand - Help!

A little while back, a dear friend asked me to build a bookstand to support an atlas which she uses pretty much on a daily basis. After talking with her and her family to gather all requirements and make measurements, I cobbled up a quick (for me) prototype outta tuba4's and assorted scrap which I quickly shellacked to glue the dust down and presented for approval of the dimensions, etc. *And* I told her that it was just a prototype and she couldn't keep it because it pains me greatly to see this collection of soon-to-be kindling in her home. Unfortunately, she loved it, but...
(Now since we all understand the relationship between good deeds and punishment, I figure you'll relate when I mention that this is the part of the story where feature creep rears its ugly head.)
... she has a need to sometimes walk around the house and sometimes let her wheelchair do the walking. So the added requirement is that this bookstand be adjustable in height. Now I've scratched my head over this for a while, been to the library, DAGS (several actually), and have to admit that I'm stuck. The deal is that it's gotta be rigid and stable. And effortless (or at least easy) to move from one position to the other. And look like furniture. (That's *my* requirement.) I've thought of cantilevering/counterbalancing, coil springs, gas springs, scissors jack, screw lifts, but nothing feels *right*.
So I fling my plea to the farthest reaches of the wreck. Any ideas? I don't reject the above mentioned methods out of hand, but I just haven't figured out how to incorporate them into something that I want to look like it belongs in a living room or study.
The range of the movement is approx. 12 inches. It will only rest in the two extreme positions. The weight of the atlas is 8-10 lbs. Did I mention that it has to be rigid and stable?
Would it help if I posted pictures of the prototype on abpf/w?
Hopefully,
Steve Stripling Huntsville, AL
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How about a pedistal stand with an internal counter ballance and pully mechanism similar to the way old windows use to operate? Make the pedistal in two hollow concentric pieces, round or square as you choose, suspend a pully near the top of the lower pedistal section, attach one end of a rope/chain to the bottom of the upper section, and a window weight to the other end of the rope/chain so that the upper section slid up and down inside the lower, balanced by the weight/pully . Some sort of friction device on the pully like a felt pad could be used to "dampen" the action. The lower pedistal section could have a decorative molding or such at the top to "hide" the difference in pedistal dimensions, and the two sections would have to be long enough to still be stable at fully extended. A felt "bushing" between the surfaces of the two pedistal pieces would also help stabilize the unit, and protect finish. The bottom could be left open for "maintenance". ;)
Hope you're using a fixed pitch font, and can decypher my rambling and poor attempt to represent my idea with ASCII...
| | - Top/inside section of pedistal | | || /0\ || || || \|| The pully is the '0', and the weight is || || || the two '*'. The rope is attached to the || || || top section, runs over the pully which || || || is suspended off the bottom on a rod or | || | such... | *| | | *| | - Bottom/outside section of pedistal | | | ------|------ \ Center rod to suspend pully
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On Sun, 19 Oct 2003 23:19:08 -0500, Steve Stripling

First question - when does it get adjusted ? Is the book on it at this time ? (I think I know, but a "two uses" stand is much easier)

My feeling would be a straight screwthread. Then disguise the lack of fixed orientation by calling it an "extra swivel feature". If you have (or buy) a wood screw cutting box then you can make a "piano stool" mechanism.
The other way (how I'd do it) is to hit the scrap yards. On the shelves and floor here I've got an ejector seat backrest adjust (perfect, but it needs 400Hz power), a dentist's chair (screw tilt and hydraulic lift) and a couple of other unrecognised screwjack arrangements.
I wouldn't do it with a pivoted arm. 10lbs is too heavy to do that conveniently. Maybe if you got the geometry right and used a strong spring in a toggle arrangement, you could make it usefully stable in the up or down positions - I'd worry about it catapulting the book upwards though.
-- Die Gotterspammerung - Junkmail of the Gods
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How about just putting 2 book rests on the stand.
1 at normal height and 1 at the wheelchair height - on the other side of the stand.

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Mount it on a drill press table
JUST KIDDING!
Seriously, how about cannabalizing some parts from a camera tripod?
--

Larry Wasserman Baltimore, Maryland
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"Steve Stripling" rot snp> So I fling my plea< snp Thanks for giving us an outlet for all the excess gray matter to go. Three ideas come to mind. One: a foot pedal / lever mechanism with a push to release mechanism. Step on the peddle to raise the 'table' and lock when it gets to the raised position. Step on it again to release the lock and lower it down to resting position. Kinda Roy Underhill'ish... Two: Compression springs in each of the legs to negate the weight. With each of the springs (say, 4 for 4 legs) holding 1/4 of the weight (roughly 15 lbs. / 4) around 3-3/4 lbs.each. The locking mechanism... perhaps something related to a large knob to friction lock the legs?? Three: Push button controlling a 'linear actuator(s)'. I searched through "American Science & Surplus" http://www.sciplus.com/ and found a possible item of use. It's item # 31355 ($29.50ea). Would require actuators, relays and limit switches built into it somewhere. Number three might be a little too Rube Goldburg'ish, but I dono.. Whew, got to stop befor gay mater uns o . . .8-o
Lurker Jon
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Thanks to all y'all what responded. Got sidetracked soon after I posted the request. SWMBO's mom is coming from SA to visit for a couple of months (this is not a bad thing) and my honey-do list suddenly gained a new floor in the kitchen, dining room, foyer, and parlor. I've outsourced most of the installation, but the demolition of the '60's linoleum (orange, black, and brown) and ceramic tile (yellow, gray, and red) was all mine. 600 square feet of joy. Habitat Re-Store got everything I didn't destroy (a considerable amount since I pulled every last nail out of the Doug Fir tuba4s), and the landfill got the half ton of mortar and tile, except tor the bit that spilled out of the wheelbarrow when the tire perf'd.
I'm still considering all the suggestions, but it will most likely be after the first of the year before I can get back to this project. I feel that the woodworking gods are smiling on me since T. graced me with a google seach string (unfortunately I cannot at this time return the favor with a brunette of the specified requirements, but the debt is acknowledged). On the other hand, last Saturday my 12" contractor's saw decided to smoke the arbor bearings and melt the linkbelt. But the good side of that is that I've got an opportunity to send the WWII in for sharpening.
Again, thanks, and I'll post the results when done.
Steve (do I use too many parentheses?) Stripling Huntsville, AL
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Check out the automated sewing machine cabinets at a sewing center. Use their electric designs. My wife has one and it is pretty innovative.

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