|Electric motors require lighter props generally than glow motors; they do not need the flywheel effect of a heavy prop to sustain ingnition and can develop more revs with light blades. The growing popularity of sport, cabin, aerobatic and scale electric aircraft has created a demand for suitable fixed blade props. The two most popular brands are Graupner and APC.
I have given the size of the bore in each prop as this has been an issue with some fliers.
APC provide a stepped hub. The hole in the front is nominally 6.5mm, but I have noticed that the size varies slightly, and even APC themselves say that this is not a precision hole. The rear side of the hub has a 9mm hole which is precison made, and this creates a step in the bore of the prop. A range of collets is supplied with each propeller to fit in this rear stepped hole to adjust the bore in a range of sizes right down to 3mm. So, you can either add the required collet, or bore out the hole to 9mm.
Click here to see propholders with a dome spinner nut that can be used to mount a fixed blade prop on your motor or gearbox shaft. Click here to see prop holders to use with a spinner.
Click here to see a range of E-props (fixed blade props for electric flight) from Aero-naut.
Fixed blade props need to be balanced, just like the folding variety. Click here to read an article on balancing props; the technique is the same even though the article refers to folding props.
Click here for a prop balancer.
Why are the prices all over the place? because it depends when I purchased the stock. Recent additions have suffered badly from the depressed eschange rate - but I am maintaining a supply of these props to keep you flying - despite the vagaries of the dollar!