hi I'm John Park look what we've got today this is a giant blade from a wind generator now a generator with blades this large can put out 20 kilowatts which is enough to power a small neighborhood today on the maker workshop we're gonna build our own wind generator one with slightly smaller blades like this now this isn't going to take you off the grid but it will charge a 12-volt storage battery and the best part about this project is that it demystifies the process of turning wind into electricity first question is where do you get a generator well you can turn a motor into a generator like this one we pulled it from an old treadmill and it's perfect for our project because it has this removable flywheel that we can attach the turbine blades to as far as the electricity part goes watch this when I attach a voltmeter to the leads and spin the shaft on the generator I get electricity about 6 volts or so this is perfect all I need to do now is attach turbine blades to this flywheel and I've got a wind generator commercial turbine blades are carefully engineered and cost a fortune a maker named Abe Connelly came up with a far cheaper solution using PVC pipe eight inches in diameter and 24 inches in length now the 8 inch diameter gives you the proper curvature to efficiently convert the straight-line motion of the wind into the rotation of the turbine and this is schedule 80 pipe which is a heavier duty PVC that makes a very strong blade now you probably won't find this at the average hardware store we had to talk to a plastic supplier to come up with a short length of this that was remaindered from another project now the first thing I'm going to do is prepare this for cutting I'm gonna clamp it to my workbench so it doesn't roll around and then this is a really cool trick I'm gonna take it an angle iron and set it on the pipe here to create a nice straight line now I'll measure five and a quarter inches and I'm actually going to create three lines for my cuts so here's the first five and a quarter mark it and set my angle iron on here if you press this on firmly you're guaranteed to get a parallel line I'm ready to cut the pipe I'm clamping it down some C clamps and now I'm gonna cut it with a saber saw using a medium fine blade take your time this is heavy duty plastic so it'll be slow going to get through it now don't forget your safety glasses and I wouldn't wear your best clothes because this is going to kick up some dust all right I finished cutting out my blanks and I'm actually going to be able to get two blades out of each of these you can see where I've marked it up that's how it's going to cut and I'm also going to remove this little notch out of here to reduce the amount of turbulence between blades now you could cut this on a bandsaw using a jig I'm actually going to use my saber saw and just clamp it to the table do half the cut and then flip it around and do the other half I finished cutting out all three of my blades now I want to shape them into a wing shape this will transfer the most wind to the generator the way to do that is to put a rounded profile into this leading edge that's the shorter one and a tapered profile into the trailing edge I'm going to use a sander to do this but I'm going to be careful to stop about two inches from the end so that I can secure my bolts here and make sure that you wear goggles and a mask for this it's gonna kick up a lot of dust all right after a good bit of sanding I've got a nice wing shape on all three blades including this really sharp trailing edge now I need a way to attach the blades to the flywheel so I've drilled two holes into the end of each blade for a quarter-inch bolt and I'm going to need to drill and tap the flywheels to attach them here's another flywheel I've put a little pattern on here I used a protractor to get three evenly spaced holes and you can find a full set of plans on our website now it's time to drill I need to thread these holes for a quarter-inch bolt so I'm gonna use a quarter inch tap wrench put a little bit of cutting oil on here and then I'll start threading it with my tap wrench and the trick here is to go in like a half turn and then back out to let some of the metal chips fall through do it nice and steady so that you get a good straight threading into the metal and once I'm all the way through the flywheel I'm done okay I've tapped all three holes in the flywheel and now I've attached the blades using one bolt each now I'm gonna measure the distance between the blade tips I want these to be perfectly even so that I know where to drill the other three holes in the flywheel now this exact alignment of the blades is critical to get optimal performance of the wind generator we need to put the generator on a frame that can point into the wind so I've built one out of some channel aluminum and I've attached a tail here now I made this tail at a sheet metal put a pattern on it and cut it out with some tin snips watch out because you get some sharp corners and edges so you can deburr that with a file now the whole frame is going to sit on a pipe flange like this that's where it's gonna pivot so I'll attach that using a bolt and washer and screw a nut on through the other side we'll attach the wind generator to a piece of one-and-a-half inch pipe you can get this at a steel yard here I've attached it to a floor stand so that I can set it up so that the frame can spin freely in the wind I'm gonna attach it to a pipe Union the way this works is I'll set these two together and screw this on but leave it just a little bit loose so that the spins freely now I'm ready to screw the frame on I'm just attaching this pipe flange to the pipe nipple and now this will turn freely so now it's time to attach the generator I've attached the motor to the frame with a couple of hose clamps just and tighten this one down and now I'm gonna get my finished blade assembly I'm going to attach this to the shaft of the motor now to make this a little easier to work with I cut a notch with a hacksaw into the end of the shaft so this way I can take a screwdriver fit it onto there and since this freewheel is threaded it's just a matter of turning this to attach the to once I get that on there should turn freely check it out beautiful the voltage produced by a wind generator is pretty uneven just like the wind you don't want to plug a device directly into this instead you want to use it to charge some batteries in this case we're using six volt golf cart batteries these are designed for a full charge and discharge cycle now if I were to hook my motor directly up to the batteries it would just spin like a propeller instead I'm gonna use a bridge rectifier this acts as a sort of gateway for electricity keeping it flowing only in one direction in our case from the generator to the batteries let's go outside and test this out we mounted our turbine on the back of a pickup truck and took it for a drive when the wind hit those blades they really started spinning I checked the voltmeter and when we got up to around 15 miles an hour the generator produced over 20 volts more than enough to charge our batteries alright my batteries are fully charged it's time to put them to work I've got this 12-volt blender I'm gonna hook this up and make myself a delicious fruit smoothie fire it up the best part is this is being made with free electricity I'm John Park I'll see you next time on the maker workshop