How to rig a pulley system with a timer......

The time would be pretty easy w/ one of the household security lighting mechanical timers if don't need it to be exceptionally precise (which doesn't sound as though would be).

A variable speed motor could be arranged by manipulating a variable speed drill it would seem with some cams, etc., ...

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On 1/15/2009 10:30 AM Norminn spake thus:

Here are my links to places that sell gearmotors:

Slow is easy, a motor out of an ice maker or some other small gear head motor will work. Mail order outfits like Hosfelt and All Surplus sell these pretty cheap. Adjustable is tougher. That either gets you to a stepper motor, gear head DC motor or some kind of variable frequency drive cobbled up from a 555 or similar time base.

Attach a bucket to the line and a couple of pulleys. Trickle water into the bucket from a slow hose.

As the bucket fills, the fabric will be drawn out. Adjust the length of the line and speed of the trickle to match your needs.

I like your idea but would get a plastic bucket as an Ice Cream container. Fill the bucket with water with a hole in the bucket. Fill the bucket and put time markings on it. Fill to the time desired. Use the bucket as the timer.

Lot's easier to put 60 marks on the line and wind one per minute :o) Unless you know the formula for amount of water, size of holes in bucket, etc. Thanks.

Gee.....I saw one possibility (gadget gurus would get to the right item more quickly). I had not remembered that there are still clocks with hands. Just a couple of months ago, I made a new wall clock for the kitchen. Is a battery clock motor strong enough? Would a cheap electrical clock be more or less strong? I guestimate the weight of the wet fabric to be no more than a pound, but I don't know about pulleys and torque and all that stuff.

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I doubt the $2.00 clock mechs you can get at craft stores will lift anywhere near a pound. You might need something like a grandfather clock mech, which might run you more than you want to spend.

Besides, you asked for "adjustable RPMs" While some clocks mechs have a "faster-slower" adjustment, I'm guessing the amount of adjustment would be minuscule.

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I have a variety motors laying around from cordless tools, microwave ovens, etc, some operate with DC voltage where the speed can be adjusted easily with a variable resistor.