I have a large wolf-dog hybrid who sheds, a lot! I have to brush him every day. A friend came by, saw the massive amount of fur he's shedding and remarked that it would be great for spinning into yarn. I looked into it and the cheapest spinning wheels I could find were $225 and made of pvc pipe. Because I have more time than money, I thought "I can make one of those!" but I still haven't found any plans for one. How do I build a spinning wheel for spinning yarn?
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.
Since I'm not really great with wood I searched for an easy wheel that could work just as well as the expensive brand name types.
After several experiments, I came across Joy of Weaving's Doorknob Spinning wheel and made a variation of it, using a chopping board, door knobs, bits of wood and mostly strong glue and a few bolts. Perhaps a couple of nails along the way. It works really well and spins superfast and smoothly. You can print out the photo pdf plans as well as watch how I spin with it on Vimeo Do a search for the Doorknob spinning wheel free plans - it works great for me.
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. However, I still spin my dog's hair this way as well as other specialty fibers, because I find it easier to manage fine fibers with a hand spindle than with a spinning wheel.
If you haven't looked into drop spindle hand-spinning, you might want to do that before investing a lot of time and effort into trying to make a spinning wheel.
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. http://porterthreads.weebly.com/store/p4/Dodec_Spinning_Wheel.html.
The Budget Wheel, seemingly derived from the Dodeca, with a circular wheel, is available on etsy.
There was a similar design published by popular mechanics, called a Penguin Quill spinning wheel. Plans are available online and posted in Pintrest.
Plans are available on Etsy to make the Thrifty Fox Spinning wheel.
These are all spindle wheels--no bobbins, flyers etc. They employ the same method as the Great Wheel/walking wheel, charkha, Mother Marion kick spindle, Navaho spindle spinning--spinning off the tip of the spindle, reversing, then reversing again to wind the yarn further back on the shaft, and out to the tip to continue spinning.
The idea behind all of these, is to run a drive belt from the shaft ofta stationary horizontal spindle, to a wheel that multipies the man power supplied from a peddle/treadle.
The Dodeca, Budget Spindle Wheel, and the Penguin Quill Wheel, all are castle style designs that stack the spindle above the wheel, above the peddle. The Thrifty Fox uses a horizontal design:
Here are sites that offer free plans:
This PDF provides plans for the wheel as either a spindle wheel, or with bobbin and flyer: http://seadreamhobbies.yolasite.com/resources/version1%20spinning%20wheel.pdf
More complicated designs that include bobbins and flyers are more involved, more costly to make...and thus, more expensive.
This plan includes bobbin and flyer: http://www.craftsmanspace.com/free-projects/spinning-wheel-plan.html
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. http://www.spinningdaily.com/cfs-file.ashx/__key/CommunityServer.Blogs.Components.WeblogFiles/spinoff/5661.Dodec-Spinning-Wheel-Brochure.pdf