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gpalterpower

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Joined: 19/07/2009
Location: Australia
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Posted: 01:42am 27 Aug 2014

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Erm.... well thanks guys. All that info is way above my thinking but I do appreciate all of you comments. Just shows there is way more to designing a mill that I first thought. Seems to be equal motions for fore and against. So im in 2 minds, so 2 ways to tackle this problem. Make a larger complete new hub and radiate the blade shafts from the centre or run with what I already have. Since the hub is allready finished I think ill go with it and keep a keen eye on things. I will suffer any consequences if they happen. Either way we will all learn from it. Any thoughts on the pic below before I weld it all together. The distance from the centre of the tower to the centre of the shaft is 100mm. Is this a good starting point or is it too far apart. Marcus.

BTW Rain here has been full on all day.

if it aint broke dont fix it!!

fillm

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Posted: 03:42pm 27 Aug 2014

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Hi GP

Yep that will be fine for blade off-set weld it up . Dont't tell me your tail angles are 20 / 20deg?

PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits

gpalterpower

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Joined: 19/07/2009
Location: Australia
Posts: 175

Posted: 12:38am 28 Aug 2014

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Hey Phill,
Not too sure how to set the tail section up. I was going on the back shed build. The tail is approx 1500mm long and sits directly behind the mill when running. It swings up and over when fully furled. I used the dimentions from this pic.

If you or anybody has a better suggestion then im all ears. Easier to change it now than weld up what I have only to find it dosent work. Marcus

if it aint broke dont fix it!!

fillm

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Posted: 08:50pm 28 Aug 2014

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Marcus,

Its not set up that way , make your tail long light and strong as possible to track the wind. The furling is done on angles not off-set measurements. Min Tail length would be blade DIA i.25 to 1.5 x R. The angles are the black magic side , as no one knows your tail design and weight , give it 3 ~ 5 deg back and 10 ~ 15 to the side , the tail does not sit directly behind like a plane , it has to counter act the blade off set so 10 ~ 15 deg.
Make it so you can easily cut and reweld is a good opt till you get it .

PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits

gpalterpower

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Joined: 19/07/2009
Location: Australia
Posts: 175

Posted: 02:54pm 30 Aug 2014

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Morning Phill.
I understand that and can make some alterations . In regards to your comment

Quote the tail does not sit directly behind like a plane , it has to counter act the blade off set so 10 ~ 15 deg.

Do you mean 10 - 15 offset from the centre of the tower as the pic donates? Or something different? Just trying to get things right before welding thing up. Regards Marcus

if it aint broke dont fix it!!

Gizmo

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Posted: 03:14pm 30 Aug 2014

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The original drawings are fine, it was a typical tail hinge angle used at the time I drew them, and the furling will work. The furling action comes on suddenly in strong winds, and there could be a bit of tail boom slamming into the stops.

Over the last few years the angles have been refined a little to give a smoother furling action. These days the angles are reduced, and fine tuning is done with tail boom length and weight. Furling starts much earlier, and you can also use a longer tail boom, which helps with tracking. Phill has done a lot of work on this, if he can suggest a couple of angles, I'll redraw the diagram to reflect the offsets for the two holes that govern the tail hinge angles.

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

gpalterpower

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Joined: 19/07/2009
Location: Australia
Posts: 175

Posted: 05:07pm 30 Aug 2014

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Thanks Glenn. Ill look forward to any response

. Marcus

if it aint broke dont fix it!!

fillm

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Posted: 05:15pm 30 Aug 2014

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Hi Glenn Marcus ,

I am not sure where on the site that specific drawing lives that you are using .

The 15 deg I have mentioned is set by where the tail at rest Stop is positioned, so at rest it positions the tail fin @15deg to oppose the force applied by the Blades Off-Set distance while the mill is operating normally.
It could be 10 to 20deg , this is not set in stone as with the pivot angles. This part is trial and error ..... How to I know how & what you have made your tail from, it could weigh 2kg or 20kg , it could be 1m or 3m .

PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits

gpalterpower

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Joined: 19/07/2009
Location: Australia
Posts: 175

Posted: 02:44am 01 Sep 2014

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Thanks Glenn and Phill,

I have some idea now of what to do. I understand there will be some fine tuning but Ill start with the basic angles as you suggested. Thanks for you help in this department. I plan to make the tail boom about 1.5 metres long. Any ideas on tail fin size. Maybe 500mm square? Ill keep you posted with info and pics. In the meantime at work I am making a cowling to go over the rotors, stators and electrics that are fitted in the naccel to keep them out of the weather.
Regards Marcus

if it aint broke dont fix it!!

gpalterpower

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Joined: 19/07/2009
Location: Australia
Posts: 175

Posted: 04:16pm 25 Apr 2015

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Well with a lot of tinkering , adjusting , changing and modifying I believe I am getting closer to set this mill in flight. All I need now is a mast. I have 2 x 6.5 metre lengths of 75 mm gal pipe. I have poured a concrete base in the ground in the backyard. A steel framework consists of 4 buried legs a metre long set into 200mm dia concrete at about 45 degrees. rough drawing of steel work

.

On these 4 threaded rods sits a metal base in which the mast sits into. the first pipe attaches to the base and can be hoisted to the vertical position from there. The second pipe hinges on the top of the first .The final height being approx. 10 metres. 2 sets of 4 guy wires are secured on the ground in a square configuration. Each point being 4 metres from the base. The guy wires then attach to the 4 and 8 meter mark above ground level. My question is. Would 4 mm gal wire rope be sufficient to hold things in place or should I go to 6mm? will post pics soon. Having a few issues uploading.

Marcus

if it aint broke dont fix it!!

gpalterpower

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Joined: 19/07/2009
Location: Australia
Posts: 175

Posted: 05:02pm 25 Apr 2015

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ok . working now

if it aint broke dont fix it!!

gpalterpower

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Joined: 19/07/2009
Location: Australia
Posts: 175

Posted: 01:11am 29 Apr 2015

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Hi all. I have updated my post with a few more pics. The last couple of drawings may not have been too informative. First is the ground level of the formed concrete in which the steel framework was placed. Beside it is the metal base that can be bolted to the 4 protruding 16mm threads with hinged pipe clamp. Wiring in the plastic bag.

Next is the base sitting in position with the pipe clamp in the upright position.

And last is the clamp in the lowered position

Im actually getting a little excited as soon I will be able to at least raise the mast. Just one step at a time.

Marcus

if it aint broke dont fix it!!

fillm

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Posted: 12:32pm 29 Apr 2015

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All looks pretty good, will look forward to you finally getting the project finished. I am sure you will find some areas you overlooked in the plan but it will not be anything you can not handle.

PhillM ...Oz Wind Engineering..Wind Turbine Kits 500W - 5000W ~ F&P Dual Kits ~ GOE222Blades- Voltage Control Parts ------- Tower kits

dwyer
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Posted: 03:30pm 30 Apr 2015

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gpalterpower

Hi Just wondering about base of the tower if you dont mind asking you question Did you weld the windmill post base yourself and what size thread bar and what grade steel are you using and notice your welding is not the best i am afraid by looking that you using general purpose welding rod instead of using low hydrogen welding rod are much better strength and and hold the parts together well and what size arc welder you have ? How ever you are doing well and l like the way you build and looking Good

Dwyer

gpalterpower

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Joined: 19/07/2009
Location: Australia
Posts: 175

Posted: 10:07pm 01 May 2015

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Thanks Phill and Dwyer.

Yes no doubt there will be some areas that have been overlooked in the plan....plan!! what plan!!

Oh ,the make it up as you go along plan!! Anyway the base was welded by a workmate of mine at the engineering company I work for. Believe me...its ok. You may have been looking at my dodgy tac welds in the pic on the top of page 6. Preety nasty I must say, but they have been tidied up too. Details of the threaded rod is in my drawing. Regarding the guy wire size , would 4 mm gal cable be sufficient or should I go the 6mm. Regards Marcus

if it aint broke dont fix it!!

dwyer
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Posts: 574

Posted: 03:57am 02 May 2015

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Regarding the guy wire size , would 4 mm gal cable be sufficient or should I go the 6mm. Regards Marcus
Depend how high the tower going be up?? and make sure using right grade steel cable not clothes line gal cable

All the best Dwyer

gpalterpower

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Joined: 19/07/2009
Location: Australia
Posts: 175

Posted: 02:52pm 02 May 2015

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Thanks Dwyer.
The tower height would be approx 10 metres as per the diagram. I will definately not be going down the clothes line path. Found this on ebay. 100m roll of 6x7 4mm cable cable for $54 plus the other stuff like thimbles and swages.

Regards Marcus

if it aint broke dont fix it!!

dwyer
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Posted: 05:22pm 02 May 2015

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That is all Good and mine tower height is 13 meter high and hasn't come down yet since 2010 and haven't done any maintenance on the tower or cable so far im happy with it Still using PhillM blades and modified oil cool Chinese gen (500 watts)

Dwyer

gpalterpower

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Joined: 19/07/2009
Location: Australia
Posts: 175

Posted: 07:48pm 02 May 2015

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Thanks Dwyer.
So....are you saying that 4mm is ample for the job? What cable cable size and configuration do you have on your 13 metre tower? Thats High!! How many sets of guys are there?

Marcus

if it aint broke dont fix it!!

Gizmo

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Posted: 08:38pm 02 May 2015

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I would use 6mm at least on a 10m tower, or bigger to play it safe. It depends on how close people are to the tower in high winds. If its in the middle of a field with no one around for a 100 meters or so, you can get away with smaller wire, if it falls, no one gets hurt.

You can run several wires together, just make sure they are evenly tensioned, so one wire isn't taking all the weight.

I have a 6 meter tower, and run 8 guy wires. Each set is two 4mm wires run together.

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

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