Treadle Wheel

Treadle wheel

I thought it would be cool to build one.  This was a perfect project for the Covid-19 hunker down drill in March through May 2020.  I have had to assemble, test, disassemble, make modifications, and reassemble the wheel 4 times for it is ready for the polyurethane coating was applied and twice more after coating applied.  A true work in progress but had time to kill.  

There are many plans for treadle wheels on the internet and in books.  Approaching mine from I want to build this without a welder and fancy woodworking tools.  Keep it simple for a single user and reduce costs.  I have complete the wheel and in testing and adjusting phase.

Weighted wheel

There are many designs using the traditional wood treadle wheel and sand weight following the Leach style wheel.  The idea behind the weighted wheel is to act as a flywheel to provide even head speed and low energy input.  A wood wheel makes shipping easy because the user adds sand after the wheel has been assembled and set into its permanent home.  A few older kick wheels use cement  to produce a weighted wheel.  I was not sure how to approach it but did not want to build a wood wheel or pour cement.  

I ended up using a 17 " galvanized oil change pan ($6) as the base for the weighted wheel.   After assembling adding brick for wheel weight I found the pan to be too flimsy.  A pieces of 5/8" plywood was cut into a circle to support the metal pan.  Wheel weights are four 9 lb sand bags placed in the pan and spaced for even distribution of weight.  

Crank shaft

The heart of a treadle wheel is the crank shaft.  It is a great excuse to buy and arc welder or contact a welding shop but trying to keep cost down and stupid simple.   Traditional 1 inch round stock is used to make the crank shaft.

The Covid-19 hunker down drill forced me to try something different.  I am using 1/2 galvanized water pipe instead of the round stock.  The outside diameter is 0.82 inch and will need to be shimmed to fit the 1 inch bearings purchased for the wheel using 1 inch steel stock. Pipe lengths are 1-12", 1-2" and a connector for the top section.  The connector allowed the height of the wheel to be adjusted in the design process and as a work around for no unnecessary travel order from the governor of Idaho.  I used a 1-6" pipe for where the treadle is attached,  2-2" for making the crank and 1-3" for bottom section below the wheel for $30.  

The crank is attached to the wheel using two flanges ($12).  If I build it again I would just drill a 1 1/4 inch hole in the center of the pan and board for the pipe to pass through.  Governor's order for not unnecessary travel presented the need for the flanges.   

A short piece of 1 " electrical conduit 8" long will be used as a bushing where the treadle connecting rod is attached.  The conduit was cut into 2.5" sections so it acted as a bearing and spacer. 

Pipe was joined using 90 degree elbows ($12).  All joints were over tightened with a large pipe wrench to prevent unscrewing while the wheel is spinning.  Hope it will hold over time.  If not may try spot welding.  

Additional thought on crank shaft pipe. 

Instead of using iron pipe what would happen if you used PVC Sch80 pipe.  In theory, the wheel will weigh about 35 LBS with the weights added.  Potential stopping weight is equal to the mass so about 35 lbs and realistically are you ever going to come to a sudden dead stop.   Sch80 pipe is the heavy duty version of PVC and used for high pressure gas lines.  PVC pipe tensile strength is measured by hanging weight from the pipe until it bends or cracks.  The tensile strength for schedule 80 with 3/4 inch diameter  is 480 lbs and 727 lbs for 1 inch pipe.   Never tried but it is on my bucket list.  

Stand and seat.

I used a doubled 2x4 strengthened by gluing to form an L.  The seat was to be a Harbor Freight adjustable mechanic seat to allow height adjustment as needed but ended up being a 2x6-14" because it was what I had on hand.  Lewiston Idaho had 22 cases of COVID-19 at the time of construction so delayed the trip for the Harbor Freight bench.

The stand legs length are 24 inches.  The top front cross member 24 inches strengthened 21 inch 2x4 glued with wood panel glue so it was 1.5 inches from edge.  I had an unopened tube of wood construction panel glue that fits a caulking gun and it was used liberally to glue all joints and as a water proof caulk.  The bottom cross member is 21 inches long with a notch cut to fit the leg.  The back leg is a  2x6 - 22.5 inch long.   Flat metal L brackets will be used on bottom 2x6 bracket for stability of bottom front brace and back leg.  

Materials need  2 -2x4x8, 1 - 2x6x8 and 4 large flat L brackets.    

Finishing Touches

Treadle Adjustment

Wheel designs on the web were 6 inches higher that mine and in test the treadle my knee was too high and the wheel was uncomfortable to use.  My work around was to add a 4 inch metal stirrup for my foot that made the treadle easier to use.  

Wheel weight

I started with 7 lbs gravel in each bag.   The wheel did not have momentum and would often stall.  After using it for a while I increased the gravel to 9 lbs per bag.  The wheel weight was still not enough so planning to use 80 lb cement to fill the wheel tray.  This should bring the weight to 60 lbs and improve speed control and allow the treadle foot to be lowered another inch for better leg action.   

Squeaks everywhere

Most of the squeaks have been solved with a coat of grease.  Final squeak is my shoe squeak on the new stirrup.

Connecting rod.  

Needs a better design.   

Treadle Wheel update

The treadle just did not work with my bad knee so having knee replaced.  I also purchased an electric sewing machine motor as a temporary fix for the knee.  Need to install motor.