The Whittaker style paddle wheel uses off-axis blades to increase efficiency and eliminate fouling. It is ideally suited for amphibious projects and applications where weeds would tangle in a normal propeller. It is low-draft and works well whether the blades dip just 3" into the water or go as deep as 13". Here's how I made one using a recycled plastic barrel and a bicycle crankset.

The Whittaker from dawn thomas on Vimeo.

What you'll use up:
1 large plastic barrel (HDPE) (the one in this Instructable is probably 30 to 35  gallons)
[NOTE: I've since learned that the BLUE HDPE barrels are far less prone to fracturing than the WHITE barrel shown in ths instructable-- so use a blue barrel if you can!]
A couple of lengths of 2x2 redwood
About 2 feet flat steel approx 1/8" thick,1-1/2"
Bicycle crank, 3-part style (the pedals come off the spindle)
30 stainless steel wood screws and 18 fender washers
Rust-inhibiting spray paint

Saws-all or scroll saw or keyhole saw
Driver or screwdriver
Table saw or mad skills with a circle saw

Here's an outline of the steps:
1) Build a couple of triangles from the wood, 20" (ish) on  a side.
2) Cut and weld the crankset to fit into the triangles. Screw the armatures to the triangles.
3) Cut 6 paddle blades from the barrel. Make them 1/6th the circumference of the barrel and 20 to 24" long.
4) Screw everything together.
5) Mount to your amphibious vehicle.

Step 1: Build a Pair of Redwood Triangles

1) Cut 6 pieces of redwood 18.5" long and having ends that are cut at 60 degrees. Redwood resists rotting in the water pretty well, so don't treat it.
2) Optionally, bevel the outer faces of these pieces. The paddle blades enclose an arc of 60 degrees because they are cut from 1/6th of a barrel (which is 360 degrees total), and a bevel of 15 to 30 degrees will help to level them out so the thrust leaves straight to the rear of the paddle wheel. If the plastic did not flex ever, then 30 degrees would be the correct angle. Because it does flex, the angle is somewhat intuitively determined.
3) Offset the corners of the triangles, and predrill and screw them together. Predrilling is important in brittle redwood. Now you've got a pair of triangles just over 20" on a side. Assemble them so there's a right and a left (see the drawing)
4) Turn the triangles so the bevel faces down and mark the centers of each leg of the triangle (approximately 10 -1/4" from the corners) to help with aligning during metal fabrication step.

Note: the blades extend past the corners of the triangles... so knowing the left triangle from the right triangle is important. Also, since we are mounting the edge of the blade to the triangles, it's important to make sure your blades point away from the axle so that the blades clear whatever frame you will build. Keeping this in mind will help you orient the bevel correctly.
<p>Hi sir, may I know what is the dimension of the multi purpose rack?</p>
<p>Yes! It's 70&quot; wide, 24&quot; deep and is built so that there are channels for the flotation barrels to naturally fit within. It extends from the handlebar and front forks about 12&quot;, to create some space between the flotation under the rack and the flotation under the pedal seat. This creates room for the pivot to work.</p>
Maybe modify to use a belt instead of a chain? Not sure if it would get slippery or not but it would solve your rusty chain issue. Looks great I may have to make one.
Hmmm, maybe! One of those toothed belts might do the job really well.
Good point maybe a tensioner as well would help.
Very nice!
The paddle blades in the picture at the top seem to be mounted on a single triangle, whereas the instructions show centralized blades with two triangles. What's the trick to making the single-triangle wheels? Those look like they would work better for my intended project. I love this idea, by the way, I've been trying to work out something like this for ages with no success. Well done.
Hmmm, I'm not sure I understand your comment. The top picture shows the two halves of the paddle wheel (see how the one side has the chain ring?) and when you watch the video, you can see how the two halves work together: one of the six blades is always in the water. <br> <br>Are you trying to figure out how to build a paddle wheel that attaches in the same way as a bike wheel? Such a thing would have a central axis and have mounting points at each end of the axle. I'll bet together we can brainstorm something that would work for you!
Oh, summer inspiration just hit!
Yay! Inspiring others feeds my soul!

About This Instructable




Bio: I just want to rock and roll all night and part of every day Facebook can't keep track of how many friends I have.
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