Hand Carved Wind Turbine Blades - 3 kW Axial Flux
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- Опубліковано 19 бер 2019
- Check out the build article and get the plans: renewablesystemstechnology.co...
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when you think his working on one blade and surprised 3 blades , just perfect
I'm so glad I found your channel, James. Your builds are both a work of art and technically brilliant. I love it! Looking forward to your next one.
Very impressed. As always
Very nice results!
Glad I found your channel, awesome stuff!
Old school pattern making! Nice to see.
Keep it up James 👍
Check out my latest project: ua-cam.com/video/yXQnydST9fw/v-deo.html
Check out the complete build video for the 3 kW Reaper wind turbine: ua-cam.com/video/EPmW-BjCiWI/v-deo.html
At 0:25 it looks like both blades failed where the mounting boss joins the blade body - you likely have some stress risers there given the size of those inside fillets. Perhaps running a bigger fillet radius would help in future, or maybe even some radial fasteners through the "wing" tips perpendicular to the axis of rotation? Great work nevertheless, wish I had your patience!
Those look amazing. I bet they'll last a long time.
Great to see you are ready to get everything together again! That was a lot of work! I though you would only carve the first and then copy-carve the other 2. Instead, you made 3 exact sculptures!
I was surprised that these new blades weight almost half of the full fiber ones. Good idea to angle the blades out! I'm dying to see them working!!
The original blade wouldn't be matched to the replacement blades. Unmatched blades would affect the balance of the fan, which leads to vibration, higher wind speeds to start rotation, and ultimately lower efficiency. To top it off, because it had been through a failure, there's a good chance it will break as well.
But, of course, the farmer in me would set the original blade aside as an emergency spare.
another great video
great work
Brilliant work and brilliant vid!
Thanks!
You are a blessing to us all. Your talent is unquestionable and awesome brother.
God is good 👏🏽👏🏽
Nice!
nice work James i keep having flash backs from the last video finger crossed
That's one still time lapse pooch you have there....... the chainsaw..... a man after my own heart.
hiya James
wow
Another idea would be to fill the mold with polyurethane foam and coating this with fiberglass.
Упорство и труд все перетрут - русская пословица) Так держать!
Round 2, is about to start, LoL 😃 good luck!
Thanks bud!
Quem ver o gerador montado , não imagina o trabalho que dá fazer !
Get the plans for this project here: renewablesystemstechnology.com/3-kw-wind-turbine.html
WoW Your Bennie Camera had my eyeballs flying all over the place. Sure hope this set don't go BALLISTIC like the last. Bummer that was. I'd never be able to produce three like blades this way. Your Amazing at this chit.
Lol, yeah I wasn't a fan of that clip either - should have shot the layup from the tripod. This set should be fine. I've got a lot of experience with wooden blades. Usually used Minwax's outdoor polyurethane finish for protection, but the fiberglass should do a much better job.
thumb up for sharing the plan, hard to calculate aerodynamics props.
that is some sick $#!+. incredible
.....good boy!
hi bro , you are amazing ! that work was really wonderfull. do you teach ?
I have a set of plastic blades that work ok, the problem is they deflect is winds higher then 15. Could I strengthen them using fiberglass and fiberglass mat?
Wow nice 👍😊 How are they preforming ? How are they doing in the wind ? They look super
Thanks! They're working great. I'm uploading a video of them eating some wind as I type.
Where did you get the measurements or dimensions for the blades
Great work! What temperature do you like to keep your shop for fiberglass layup?
Thanks! I usually keep the shop at around 10-15° in the winter under normal circumstances (I work up a sweat easily), but turn the heat up to between 15-20°C when working with resins and epoxies.
this reminds me of a technique of forming something in foam board and then covering in fiberglass. dunno how strong it would be but i've seen it used for custom vehicle bodies..
Some blade sets are actually made with foam cores. It doesn't provide much rigidity (if any), but it does provide a shape for the fiberglass. I had considered it, but have a 5 gallon pale of polyester resin to use up, and that would've eaten through the foam within minutes of wetting the glass. A person would have to use epoxy over a foam core, instead of resin.
@@JamesBiggar I'm also curious about the mass of the blade - is it better to have the blade heavier, to have more inertia once it gets spinning, or lower weight, to start spinning more easily? Like everything, probably a trade-off.
In order to build inertia, the blades first need to spin. The heavier the blade is, the more wind power it will take to get them started, so the lighter the better. It doesn't take long to reach cut-in voltage once they start, if they're designed properly (cut-in voltage is the minimum voltage needed to begin charging a battery, which is determined by the coil winding, magnetic flux strength, and the size/TSR of the blades at a given wind speed). An axial flux turbine experiences no resistance in the generator by design, compared to most radial flux machines that have a cogging resistance inherent in the gen design to overcome. Axial flux turbines have only bearing friction and air resistance to deal with. Subsequently, it doesn't take near as much inertia to keep an axial flux rotor spinning and responsive to wind speed fluctuations, as it would for a radial flux turbines. In the previous video I showed the turbine spinning in just 2-3 mph wind. Most radial flux turbines won't even startup until the wind speed reaches at least 5 mph (typical start up rating), and aren't as responsive to wind speed fluctuations because the added cogging resistance wants to slow the rotor down sooner when there's an interruption in the wind stream. But even for a cogging turbine, more weight wouldn't help because it would just increase the startup speed requirement. This could be mitigated by designing a wider root for more startup torque, but that would limit top speed potential. So yes, there is a trade off when it comes to mass/weight, speed and torque. Generally speaking, if you want more torque, then you'll have to sacrifice some top speed potential, which lowers peak power potential. Vice versa if you want more speed, and either one affects the size and pitch of the blade chord. A lot of torque shouldn't really be needed unless a person needs to do heavy work at a low rpm, like pumping water or air or something. Electrical generation requires speed, because voltage potential is proportional to speed. The faster the rotor turns, the higher the voltage the gen will produce. The best materials for making blades are those with the highest strength to weight ratio, especially when making wide, torquey blades.
Would it be possible to make a follower type mechanism like a key cutter? That way something like a router can be used to copy an existing blade.
You mean, like my router duplicator? www.resystech.com/router-duplicator
Smart thinking ;) Lol, this duplicator is a bit too small for these blades though. I have a CNC kit ready to build, but am torn on using it or building another/better duplicator. We'll see what happens.
Great project thanks for sharing. I was wondering why You didn't use Your prime blades You had already made ? They were to elastic or You just threw the form away ??
Thanks! You must be a few videos behind lol. They were destroyed by a wobbly tower. This method was the most affordable means to replace them. I also took the opportunity to change the geometry a bit, and adjust the TSR. Everything is working great now.
@@JamesBiggar thank You for replying. I cant imagine how wobbliness of tower can affect the blades that are so far from it. Respect for double work. I hate that when it comes to redoing ANYTHING that was once considered done. ;)
Thanks. Anything worth doing, is worth doing right. Connecting with the tower is possible if it wobbles enough. Most of the tower was secure, but the pipe was undersized for the weight of the turbine and the top 6 ft is what caused the problem - it moved, but the rest below it didn't. If the tower wobbled/bent below the blade tips then it probably wouldn't have been a problem, but instead it bent from the blade tips up in an arch, which directed the tips into the tower instead of remaining parallel with it. This is why tower pipe size is important regardless how many guys are used - the distance between the blade tips and the generator is still unsupported because guys can't be placed there, so it has to be rigid pipe. It's hard to see in the video because the turbine is almost directly facing the camera and that's the direction of the wobble, but it moved a good 6" at the top when I was outside watching it when the accident happened. There was only 10" of clearance between the blades and the tower, which would have been fine if the tower didn't wobble. But combined with normal blade deflection (which is also hard to see in the video but isn't any more than 4-5"), it was a recipe for disaster. What I used for tower material would have worked fine for a smaller micro turbine with short blades, but a tower needs to be absolutely rigid for turbines this large. The turbine itself weighs as much as I do, which is compounded by the wind load, and each blade is taller than I am. It's no lawn ornament lol.
You could also try to prevent the mast from starting wobble in high wind. Add spiral sheet of aluminium to circle around the top half of the mast, just like they do with industrial metal chimneys. Check physics.stackexchange.com/questions/75459/why-do-chimneys-have-these-spiral-wings
That would work. I've opted for tacking some flat bar to the tower. Similar to this idea, but straight up and down on four sides instead of spiraled (which would be beyond my abilities to do).
So what caused the first set to fail?
revenge!!!
Усилить лопасти - это хорошо, но я думаю нужно ещё добавить жёсткости пилону...
Вы имеете в виду башню? Вы правы, но я уже об этом позаботился ;)
Ок, буду ждать новые видео) Искренне желаю Вам успеха!
James, you work like you are a machine! I was curious if the blades could have benefited from being laminated with Kevlar instead of fiberglass cloth?
Of course, or carbon fiber or any other stronger synthetic material - IF a person can justify the cost. I can't, that's why I use fiberglass, and why industry leaders do the same. Its contribution to the total $/watt for the turbine, ie: cost efficiency, is the determining factor in the end. If an alternative isn't cost efficient, it's not worth the bother because people won't buy a product that's unnecessarily more expensive than the competition when the end goal for most home and business owners is maximizing energy cost savings. Despite my previous mishap with the tower destroying the hollow blades, fiberglass has been proven to be more than sufficient by many, many others over the years. In this case, fiberglass wasn't really required anyway. Glue-laminated wood is more than strong enough for blades - it's the common go-to material of choice for micro turbine builders, specifically pioneers like Hugh Piggott and the folks at Otherpower. I've been using wood blades for over a decade - 0 problems. I just added the fiberglass for better protection from the elements than what a standard polyurethane finish would provide.
@@JamesBiggar I stand corrected!
Lol, I'm speaking in general terms, so you never really know for sure unless you price it out. Kevlar would inevitably be more expensive than fiberglass, but that doesn't mean it would be impossible for someone to make a cost efficient turbine with kevlar blades, especially if they live in an area with high utility rates. I live in Canada, the majority of the main grid here is powered by hydro and subsequently utility companies charge some of the lowest rates in the developed world. That makes it a bit difficult for me to financially justify experimenting with more expensive materials with these projects.
@@JamesBiggar LOL I get what you mean by being cost effective.
I take it you will be upgrading the mast before you install the new blades?
For sure. Picking up the flat bar for reinforcement first thing on monday. Hope to have it back in the air by the end of the week
Wow that looks like a lot of work! Couldn't we just make inefficient flat angled blades out of sheet metal and compensate for their slowness by making them Giant?
Of course it would be slow so the generator would need to work at a low RPM or else have gearing
Yep, it's a lot of work but someone has to do it and I have no interest in forking out another $600 for new blades when I have the will and ability to make my own lol. I build houses for a living, so this is a nice reprieve from my day to day grind. It's not as difficult as it might seem.
In short - no, you would be wasting your time with that method for a number of reasons. I used to think that way over a decade ago, when I had no idea about how generating lift worked, why it's important not just for power efficiency but also cost efficiency, and assumed that just bolting on a few 2x4's with a slight angle would suffice. It doesn't, and it was really frustrating in those early days. I've since learned to take helpful advice from industry professionals.
Flat blades will work on a drag based VAWT, but this is a HAWT. HAWT's need to convert the drag force into lift to perform efficiently (and far more efficiently than a VAWT, which is why they're more popular). This isn't quite like substituting a tracking system for more solar panels to make up for efficiency losses. There are fluid dynamics involved. If you can't produce lift effectively, then the blades aren't going to turn or will barely turn, will create way too much turbulence if/when they do, and will stall out in medium-high winds before you have a chance of producing anything useful. In order to cut in and actually work, your generator would have to be wired for extremely low rpm's, and the rotor would need to be extremely large, so you're thinking is somewhat correct here. But again, it won't be efficient. In power or cost. The latter being the key determining factor when it comes to practicality. This is the price for trading performance for convenience - if your turbine isn't an efficient producer, then it's going to cost you $ to compensate for that.
HAWT blades are designed using blade element momentum theory that incorporates a proper airfoil with a twist distribution called "washout" that accounts for the differing relative wind angles and speed ratios at different stations along the length of the blade. This optimizes the blade to wind speed ratio relative to the relative wind angle (which is different than the actual wind angle) by keeping the angle of attack the same throughout the blade. There's no substitute. A person could make straight blades with an airfoil for slightly better performance than an angled 2x4 or simple PVC pipe blade , but it doesn't take into account that the relative wind angle differs along the length of the blade on a HAWT, and therefor won't produce an optimal lifting force.
I've used aluminum sheeting on a LENZ II VAWT before. Metal is probably the worst material choice for turbine blades, especially blades this large. Its weight to strength ratio is way too high, requires riveting, and fatigues too easily. Blades need to be strong, but somewhat flexible. If a sheet metal blade deflects under a high wind load, it likely won't return to its original shape. This is why you won't see metal blades on most micro wind turbines, and especially not on commercial turbines. These are made from fiberglass and wood because they have the best properties for this application.
@@JamesBiggar yes these are more popular for a reason like you say. I've got windmills on my mind lately ever since I put up my brother's solar system in an area that regularly gets 60 mile-an-hour wind. All his neighbors windmills lose their blades so it got me thinking of the big old windmills you see in the movies. I was thinking of taking the rear end of a truck and propping it up to take advantage of the gear reduction within the unit. Also because the bearings are strong enough to hold a truck I figure it could support a gigantic blade system that hopefully would be inefficient in high wind so it does not fly apart? I could put a dump load to the water catchment tank which would never successfully heat up because the wind is blowing on it all the time
would it be possible to build them out of carbon fiber? without being cost prohibitive
Depends on availability. I can't justify it, personally. But that isn't necessarily the case for everyone.
Will you sell a set?
Sorry, not just yet. I want to give the turbine some time in the air first, give it a good test before I start thinking about selling components. Would hate to sell something potentially faulty. I have good faith the blades will be fine, but they're still a slightly new design and should be put to the test first.
@@JamesBiggar 10-4. Makes good sense. I have an Axial being built by a good guy and will be flying it this Summer at 10,000' in Colorado. Will just be using the cheap blades from CMS to start - 8.2' diamater. Probably wise for me to test for a season as well. Thanks
What about carbonfiber single tow run lenth ways, and then a carbon cloth wrap to reinforce? With maybe S glass? Over a foam or easier to work with lightweight wood? Just thinking would it be worth it? I guess the old ones were fine, just the mishaps! I don't guess it would be vost effective, to have huge blades that weigh 2oz, and last forever, and cost $50+ each, when wood works just as good, the little power they might make isn't worth it... Maybe foam, and a few layers of continuous roving fiberglass, with a bit of glass matting, then maybe a woven cloth outer, shouldn't be too bad, if bought from the right place, and some epoxy resin, maybe unwaxed polyester and a gelcoat with UV protection, but I was thinking I may make some from PVC pipe, like 6" sch. 40, about 46"-50" with aluminum flat bar .125" x 2"up to maybe half the lenth, giving something to bolt to the hub. About 10" x .250" aluminum hub. On a generator capable of 2kw, 5 blades, I don't have alot of fast wind, but plenty of little breeze just a idea, I don't want to put alot in to it, since it may not produce power here, I'm leaning toward a water wheel, since I have a little spring, with a bit of resivor I can make about 1kw, for about 12hours a day, even more when it rains, being off grid, that's when its needed! I'm thinking I will atleast put up a small turbine, because it gets windy when there is no sun and storms close by, " exactlywhen I will need the power" 600-1200w water power, and 300-500+/- wind power, and maybe 100-200 from my panels on a stormy day, I should be OK, I do have a DC generator in the works, just incase! Sorry I'm rambling badly!! Great video, got my mind working!!! Thanks!!
The problem with foam is that you'll probably have to use epoxy instead of polyester resin because resin will eat the foam during the curing process and destroy the cast (I learned this the hard way). But if you use epoxy, then you're limited to just using fiberglass cloth or carbon fiber cloth - no matting for extra thickness/rigidity. The oriented strands in fiberglass mat are bonded together with a glue that dissolves when it comes in contact with resin, but it doesn't dissolve in epoxy. This is important because the mat won't wet well with epoxy, and will create a subpar cast (see Boatworks Today's latest video comparison that demonstrates this).
Carbon fiber is a great idea, if the cost was justifiable. I haven't yet been able to find it for the right price. Fiberglass and wood already pushes the limit for cost efficiency (ie: its contribution to the total $/watt for the turbine). But that doesn't mean no one else can. Like I always tell folks, material costs will depend on their availability in a person's area. The further materials have to be shipped, the less cost efficient the end product will be, in general.
If you have a good enough source, then I think hydro would be a good place to start. 12 hrs of production/day is ~4X longer than what a typical PV array will generate power for - most areas in North America only get 4-5 hrs of peak sunlight hours/day on avg annually (that is, when the intensity of the sun is at or above 1000w/m2). Go for it!
@@JamesBiggar what if you greased up the foam with vaseline first? Would that protect it from the resin? Just a thought, I have zero experience in this arena.
I wouldn't chance it. I had painted the molds for the old fiberglass blades and used a liberal amount of vaseline as a release agent for the casts, and the resin still ate away at the paint. Didn't hurt the molds because they're resin too, and the vaseline still did a great job as a release agent, but it didn't protect the paint.
judging by the date of this video....I take it that the fiberglass blades didnt fare to well
Nope. The tower took them out.