I went through this a few years ago and wrote it up on my website. Prices and links are all Australian, but the idea stands.
The big discovery for me was that there are people who are in the business of finding waterproof drums and reselling them. If you can find one of those in your area they will offer a range of shapes and sizes, and possibly trade-off a ...
FYI - you don't have to have a spinning wheel to spin small to moderate amounts of yarn. A hand-spinning spindle will work great, is much less expensive to buy and far less complicated to make, and is also very portable. I spun great yarn using a top whorl drop spindle for a couple of years or so before I finally (mostly) moved on to using a spinning wheel. ...
I'm not sure about donating leftover bits... But for recycling/reusing, what I normally do is grab a new bar, and at the end of my shower/bath, get both the new bar and the small used piece(s) wet and squeeze them together relatively firmly. Leave it in the soap dish / on the shelf and they will dry that way.
The next time you shower/bathe, you'll have a ...
A car or household lubricating oil, such as WD-40 or 3-in-One oil (both are brand names in the UK) will dissolve the label glue. Put one or two drops on the glue residue and rub with, say, a paper towel for a few seconds, and the glue should start to come off.
I haven't tried using vegetable oils, so I don't know if any of those will work.
That's great to have a constant source of yarn - from your pet. I saw a lady who knitted items for sale using her dog's fur.
I've been studying about spinning wheels and how to spin only in the past few months. I've come to the conclusion that a spinning wheel is actually a sped up version of a drop spindle and it's also a lot of fun to spin with.
I've found an abundance of ~50 gal. food grade barrels which I use for rain barrels on Craigslist and other local papers etc. I certainly consider this up-cycled and by the time you spend making another type of container water tight, the small cost far outweighs this in my experience. Further, these containers come with a threaded, 2-piece screw type lid. ...
The best solvent I have ever found for stubborn materials is (surprisingly) "NZ tea tree oil".
It also does not seem to harm most surfaces - a paradox.
It's not known to be especially poisonous - it is sold as a health product.
The genuineness of the health claims made for it are unknown to me, but it seems close to the ideal solvent to have on hand.
I just realized that direct heating with a flame does a pretty good job. Boiling water wasn't enough, but heating with a flame seems to do the trick. After heating, wiping with a rag takes the glue off.
There is still the smallest amount of residue left after the flame-and-wipe. I'll give @Claran's oil suggestion a try and compare the results.
Another option would be to use a cheese grater to turn the soap into flakes for use as laundry soap. Lux, in fact, is available as laundry flakes from the supermarket.
Cannot comment on the biodegradability of Mysore Sandal, however the MSDS for Lux claims the product is biodegradable. Unfortunately no information on eco-toxicity.
It seems the bottom line of the question is low cost spinning wheel.
The Dodeca wheeldesign is available free on line. This has been noted in another post. Porter also sells this wheel and a similar wheel at a very low cost for a spinning wheel.
The Budget Wheel, seemingly derived ...
We set them in a jar lid. With a hole in the bottom to drain. Set on sink. Small left over soap is good for washing your hands. Once supper small. Throw in bucket with a little water. Use to soak panties overnight & such. Before washing by hand.
Here there is a very interesting case study by the government of Oregon. It is not as specific as you want but they give a lot of figures to understand the cost of processing and collecting glass and to give a quantitative estimate of the average saving caused by recycling.
You can find much more examples googling , like this British one, which is much more ...
You are track of a useful idea here, but the ceiling space is not the place to use it. I have actually asked our local waste management municipality if it's realistic to pull a stream of waste styrofoam from the landfill sorting process. While they haven't asnwered me, because of styrofoam's low density, separating it should be straight forward.
After looking at the rosemary knits spinning wheel (from the comments) I found a wheel called the dodec spinning wheel. It makes a fully functional wheel with pedal out of a ten foot board.