## Re: Hi guys..

Expand Messages
• It could be done, but it would be complex, and prone to inefficiency or failure. Depending on how many phases your try to run, you would need a slip ring
Message 1 of 12 , Feb 1, 2008
It 'could' be done, but it would be complex, and prone to
inefficiency or failure. Depending on how many phases your try to
run, you would need a slip ring and brush set for each phase. 3
phase would be complex, 5 or 7 phase could be absurd.

As a consolation, the extra mass of the accepted set up with
rotating magnets acts as a flywheel and helps smooth out the
rotation.

A few days ago some members were discussing whether contra-rotating
blade sets could be managed, with one blade driving the magnets, and
the second driving the coils. Similar problem.

Another couple of things to consider with the contra-rotating props
would be 1) You will need to space the two blade sets quite a
distance apart in order to not have potential blade strikes. In a
gusty or variable wind direction situation, the yawing of the wind
turbine will cause the two blade sets to flex in opposite
directions, so that a blade strike could (if not properly spaced)
occur. The extra long shafts required would require much stiffer
and heavier shafts, which increase the cost, the wieght, the cost of
the tower etc.etc.

( Look up gyroscopic procession, it will explain it better than I
can here, but basically a force applied to a rotating object will
cause the plane of rotation to move at a location 90 degrees away
from the location where the force is applied. This how helicopter
rotor systems are controlled).

2) The downwind blade system will likely need to be about 15%
larger diameter than the upwind blade system, since the upwind
system will take away some of the energy, and also disrupt the
airflow (turbulence) to the down wind system. This would have the
advantage of having the blade tips of the two systems far enough
apart so they do not cause aerodynamic problems if the blade tips
approach or exceed the speed of sound.

Since the tower cost of many systems exceeds the cost of the wind
turbine/generator set, a contra set up might make sense if you have
space for only one tower, but the extra cost of the dual set up plus
increased maintenence costs might or might not be made up by the

The whole idea of the Axial Flux generator is to be simple and low
cost, I don't see the need to overly complicate a simple system.

My .02, all standard disclaimers apply.

Michael Grogg

--- In axialflux@yahoogroups.com, "mart85" <halemart@...> wrote:
>
> I am trying to build a generator, and I have downloaded the files
that
> you have for a windmill design here and I see the sandwich of the
coil
> between two sets of opposite magnets.
>
> I had an idea, but not sure if anyone had tried it, has anyone
tried
> to rotate the coil instead of rotating the magnets? It seems to
me
> that there would be less force needed to turn only the coil verses
> turning both sets of magnets.
>
> Thanks for you input.
>
> Mart.
>
>
> To get an idea of my application you may visit my video :->
>
>
> thanks again.
>
• Ok, If you look at my video, I am not building a windmill, but rather something simpler. I will use multiple phases, and I will put the bridge rectifiers
Message 2 of 12 , Feb 1, 2008

Ok,

If you look at my video, I am not building a windmill, but rather something simpler.

I will use multiple phases, and I will put the bridge rectifiers inside the PVC and then I will use each hard drive bearing on each side to output the current.  ( I tested putting current thru the bearings and it worked for me.

I am thinking one could do the same with your windmill as you could put the bridge rectifiers inside the resin and then have two outputs.  In your case, it may be more difficult, but I think it will work for me.

Mart

From: axialflux@yahoogroups.com [mailto:axialflux@yahoogroups.com] On Behalf Of mgrogg51
Sent: Friday, February 01, 2008 10:26 AM
To: axialflux@yahoogroups.com
Subject: [axialflux] Re: Hi guys..

It 'could' be done, but it would be complex, and prone to
inefficiency or failure. Depending on how many phases your try to
run, you would need a slip ring and brush set for each phase. 3
phase would be complex, 5 or 7 phase could be absurd.

As a consolation, the extra mass of the accepted set up with
rotating magnets acts as a flywheel and helps smooth out the
rotation.

A few days ago some members were discussing whether contra-rotating
blade sets could be managed, with one blade driving the magnets, and
the second driving the coils. Similar problem.

Another couple of things to consider with the contra-rotating props
would be 1) You will need to space the two blade sets quite a
distance apart in order to not have potential blade strikes. In a
gusty or variable wind direction situation, the yawing of the wind
turbine will cause the two blade sets to flex in opposite
directions, so that a blade strike could (if not properly spaced)
occur. The extra long shafts required would require much stiffer
and heavier shafts, which increase the cost, the wieght, the cost of
the tower etc.etc.

( Look up gyroscopic procession, it will explain it better than I
can here, but basically a force applied to a rotating object will
cause the plane of rotation to move at a location 90 degrees away
from the location where the force is applied. This how helicopter
rotor systems are controlled).

2) The downwind blade system will likely need to be about 15%
larger diameter than the upwind blade system, since the upwind
system will take away some of the energy, and also disrupt the
airflow (turbulence) to the down wind system. This would have the
advantage of having the blade tips of the two systems far enough
apart so they do not cause aerodynamic problems if the blade tips
approach or exceed the speed of sound.

Since the tower cost of many systems exceeds the cost of the wind
turbine/generator set, a contra set up might make sense if you have
space for only one tower, but the extra cost of the dual set up plus
increased maintenence costs might or might not be made up by the

The whole idea of the Axial Flux generator is to be simple and low
cost, I don't see the need to overly complicate a simple system.

My .02, all standard disclaimers apply.

Michael Grogg

--- In axialflux@yahoogrou ps.com, "mart85" <halemart@.. .> wrote:

>
> I am trying to build a generator, and I have downloaded the files
that
> you have for a windmill design here and I see the sandwich of the
coil
> between two sets of opposite magnets.
>
> I had an idea, but not sure if anyone had tried it, has anyone
tried
> to rotate the coil instead of rotating the magnets? It seems to
me
> that there would be less force needed to turn only the coil verses
> turning both sets of magnets.
>
> Thanks for you input.
>
> Mart.
>
>
> To get an idea of my application you may visit my video :->
>
>
> thanks again.
>

• ... Mart, Slip rings and commutators all are maintenance prone. At high current they wear out and are not easy to repair on a 100 tower. So how do you plan
Message 3 of 12 , Feb 3, 2008
mart85 wrote:
> I am trying to build a generator, and I have downloaded the files that
> you have for a windmill design here and I see the sandwich of the coil
> between two sets of opposite magnets.
>
> I had an idea, but not sure if anyone had tried it, has anyone tried
> to rotate the coil instead of rotating the magnets? It seems to me
> that there would be less force needed to turn only the coil verses
> turning both sets of magnets.
>
Mart,

Slip rings and commutators all are maintenance prone. At high current
they wear out and are not easy to repair on a 100' tower.

So how do you plan to get the power from the coils to the outside world?

--
David G. LeVine
Nashua, NH 03060
• ... You really are a glutton for maintenance! Bearings, which are not designed for current flows, have two problems as brush systems. 1.) DC current through
Message 4 of 12 , Feb 3, 2008
Mart Hale wrote:

Ok,

If you look at my video, I am not building a windmill, but rather something simpler.

I will use multiple phases, and I will put the bridge rectifiers inside the PVC and then I will use each hard drive bearing on each side to output the current.  ( I tested putting current thru the bearings and it worked for me.

I am thinking one could do the same with your windmill as you could put the bridge rectifiers inside the resin and then have two outputs.  In your case, it may be more difficult, but I think it will work for me.

Mart

You really are a glutton for maintenance!  Bearings, which are not designed for current flows, have two problems as brush systems.

1.) DC current through bearings results in metal transfer from the (-) negative side to the (+) positive side as well as significant heat loads ()which reduces life.)

2.) Bearings tend to be hydrostatic devices which "fly" on a microscopic film of oil unless preloaded, oil is nonconductive.  Preloaded bearing sets are pretty easy to buy, but they are expensive and difficult to use.

Why look for trouble?

```--
David G. LeVine
Nashua, NH  03060```
• Thank you for your insights. Again, I am thinking outside of the box, so to do so, I have to build my own box :-) I am using hard drive bearings, so they are
Message 5 of 12 , Feb 3, 2008

Again, I am thinking outside of the box, so to do so, I have to build my own box J

I am using hard drive bearings, so they are free for me, so nothing on the cost, and they last a LONG time.

The reason I am going thru such trouble is my device does not have much torque, this being said, I have run this device off of two batteries

for well over 2 weeks time without recharging.    All I am attempting to do is to take advantage of the mechanical force the device gives.

Right now, I have it setup with the electricity flowing thru the hard drive bearings.    ( Took me all day Saturday to make the coils, make a delta setup with the coils

and make all of the connections within the PVC with the bridge diodes inside.   I cannot yet say how well this is working, as I need to work out a few bugs..

If this does not work, I figure, it is very easy to go back to the other way,   I have so far turned the wheel a few times and it did indeed get current thru the bearings, but much more work I will need to do in order to clean up my setup, and see if I can improve it to have less work involved in setting up.

It just seems to me that the shaft will be easier to turn, if there is less weight of the magnets to turn, and I am willing to put extra effort to explore this possibility.

My setup will stay indoors and has to be monitored anyway,  I do think in time, I will find better methods of getting the electricity out ( perhaps transmit wirelessly a Tesla coil  or a spark gap?   ( I guess I love thinking outside of the box, even it it does mean I do get very lost at times.

I want to thank you for pointing out the systems problems.   It is not practical for a windmill ( something you have to pull down out of the air everyday ) , but I think it is good for a hobby.

I do want to say a BIG THANK YOU to whoever put together the directions in the PDF found on this group of building the coils.    They are very very well done and even I can follow them J

------------------------
You really are a glutton for maintenance!  Bearings, which are not designed for current flows, have two problems as brush systems.

1.) DC current through bearings results in metal transfer from the (-) negative side to the (+) positive side as well as significant heat loads ()which reduces life.)

2.) Bearings tend to be hydrostatic devices which "fly" on a microscopic film of oil unless preloaded, oil is nonconductive.  Preloaded bearing sets are pretty easy to buy, but they are expensive and difficult to use.

Why look for trouble?

`-- `
`David G. LeVine`
```Nashua , NH
03060```
• hi, my name is joe and this is my first post here, i am a machine repairmen at a large forge... and one of the first things drilled into us is if you weld
Message 6 of 12 , Feb 3, 2008
hi,
my name is joe and this is my first post here, i am a machine
repairmen at a large forge... and one of the first things drilled into
us is if you weld something, the ground and rod HAVE to be on the same
side of a bearing... this is the same thing you are planning on doing.
The reason for this is as David said, the bearings are not solid to
the races, so the electricity has to 'arc' across the gap... this,

1)destroys the balls, or
2) welds them in place

joe

--- In axialflux@yahoogroups.com, "Mart Hale" <halemart@...> wrote:
>
> Thank you for your insights.
>
>
>
> Again, I am thinking outside of the box, so to do so, I have to
build my own
> box :-)
>
>
>
> I am using hard drive bearings, so they are free for me, so nothing
on the
> cost, and they last a LONG time.
>
>
>
> The reason I am going thru such trouble is my device does not have much
> torque, this being said, I have run this device off of two batteries
>
> for well over 2 weeks time without recharging. All I am
attempting to do
> is to take advantage of the mechanical force the device gives.
>
>
>
> Right now, I have it setup with the electricity flowing thru the
hard drive
> bearings. ( Took me all day Saturday to make the coils, make a delta
> setup with the coils
>
> and make all of the connections within the PVC with the bridge diodes
> inside. I cannot yet say how well this is working, as I need to
work out a
> few bugs..
>
>
>
> If this does not work, I figure, it is very easy to go back to the other
> way, I have so far turned the wheel a few times and it did indeed get
> current thru the bearings, but much more work I will need to do in
order to
> clean up my setup, and see if I can improve it to have less work
involved in
> setting up.
>
>
>
> It just seems to me that the shaft will be easier to turn, if there
is less
> weight of the magnets to turn, and I am willing to put extra effort to
> explore this possibility.
>
>
>
> My setup will stay indoors and has to be monitored anyway, I do
think in
> time, I will find better methods of getting the electricity out (
perhaps
> transmit wirelessly a Tesla coil or a spark gap? ( I guess I love
> thinking outside of the box, even it it does mean I do get very lost at
> times.
>
>
>
> I want to thank you for pointing out the systems problems. It is not
> practical for a windmill ( something you have to pull down out of
the air
> everyday ) , but I think it is good for a hobby.
>
>
>
>
>
> I do want to say a BIG THANK YOU to whoever put together the
directions in
> the PDF found on this group of building the coils. They are very very
> well done and even I can follow them :-)
>
>
>
>
>
>
>
>
>
>
>
>
>
> ------------------------
> You really are a glutton for maintenance! Bearings, which are not
designed
> for current flows, have two problems as brush systems.
>
> 1.) DC current through bearings results in metal transfer from the (-)
> negative side to the (+) positive side as well as significant heat loads
> ()which reduces life.)
>
> 2.) Bearings tend to be hydrostatic devices which "fly" on a microscopic
bearing sets
> are pretty easy to buy, but they are expensive and difficult to use.
>
> Why look for trouble?
>
>
>
>
> --
> David G. LeVine
> Nashua, NH 03060
>
• Hi, Thanks duly noted, Mart _____ From: axialflux@yahoogroups.com [mailto:axialflux@yahoogroups.com] On Behalf Of rem3win Sent: Sunday, February 03, 2008 9:14
Message 7 of 12 , Feb 3, 2008

Hi,

Thanks duly noted,

Mart

From: axialflux@yahoogroups.com [mailto: axialflux@yahoogroups.com ] On Behalf Of rem3win
Sent: Sunday, February 03, 2008 9:14 PM
To: axialflux@yahoogroups.com
Subject: [axialflux] Re: Turning the coils instead of the magnets in the generator.

hi,
my name is joe and this is my first post here, i am a machine
repairmen at a large forge... and one of the first things drilled into
us is if you weld something, the ground and rod HAVE to be on the same
side of a bearing... this is the same thing you are planning on doing.
The reason for this is as David said, the bearings are not solid to
the races, so the electricity has to 'arc' across the gap... this,

1)destroys the balls, or
2) welds them in place

joe

--- In axialflux@yahoogrou ps.com, " Mart Hale " <halemart@.. .> wrote:

>
> Thank you for your insights.
>
>
>
> Again, I am thinking outside of the box, so to do so, I have to
build my own
> box :-)
>
>
>
> I am using hard drive bearings, so they are free for me, so nothing
on the
> cost, and they last a LONG time.
>
>
>
> The reason I am going thru such trouble is my device does not have much
> torque, this being said, I have run this device off of two batteries
>
> for well over 2 weeks time without recharging. All I am
attempting to do
> is to take advantage of the mechanical force the device gives.
>
>
>
> Right now, I have it setup with the electricity flowing thru the
hard drive
> bearings. ( Took me all day Saturday to make the coils, make a delta
> setup with the coils
>
> and make all of the connections within the PVC with the bridge diodes
> inside. I cannot yet say how well this is working, as I need to
work out a
> few bugs..
>
>
>
> If this does not work, I figure, it is very easy to go back to the other
> way, I have so far turned the wheel a few times and it did indeed get
> current thru the bearings, but much more work I will need to do in
order to
> clean up my setup, and see if I can improve it to have less work
involved in
> setting up.
>
>
>
> It just seems to me that the shaft will be easier to turn, if there
is less
> weight of the magnets to turn, and I am willing to put extra effort to
> explore this possibility.
>
>
>
> My setup will stay indoors and has to be monitored anyway, I do
think in
> time, I will find better methods of getting the electricity out (
perhaps
> transmit wirelessly a Tesla coil or a spark gap? ( I guess I love
> thinking outside of the box, even it it does mean I do get very lost at
> times.
>
>
>
> I want to thank you for pointing out the systems problems. It is not
> practical for a windmill ( something you have to pull down out of
the air
> everyday ) , but I think it is good for a hobby.
>
>
>
>
>
> I do want to say a BIG THANK YOU to whoever put together the
directions in
> the PDF found on this group of building the coils. They are very very
> well done and even I can follow them :-)
>
>
>
>
>
>
>
>
>
>
>
>
>
> ------------ --------- ---
> You really are a glutton for maintenance! Bearings, which are not
designed
> for current flows, have two problems as brush systems.
>
> 1.) DC current through bearings results in metal transfer from the (-)
> negative side to the (+) positive side as well as significant heat loads
> ()which reduces life.)
>
> 2.) Bearings tend to be hydrostatic devices which "fly" on a
microscopic
bearing sets
> are pretty easy to buy, but they are expensive and difficult to use.
>
> Why look for trouble?
>
>
>
>
> --
> David G. LeVine
> Nashua ,
w:st="on">NH 03060
>

• http://www.vibanalysis.co.uk/technical/electric/electric.html rem3win wrote: hi, my name is joe and this is my first post here, i am a
Message 8 of 12 , Feb 3, 2008
http://www.vibanalysis.co.uk/technical/electric/electric.html

rem3win <rem3win@...> wrote:
hi,
my name is joe and this is my first post here, i am a machine
repairmen at a large forge... and one of the first things drilled into
us is if you weld something, the ground and rod HAVE to be on the same
side of a bearing... this is the same thing you are planning on doing.
The reason for this is as David said, the bearings are not solid to
the races, so the electricity has to 'arc' across the gap... this,

1)destroys the balls, or
2) welds them in place

joe

--- In axialflux@yahoogroups.com, "Mart Hale" wrote:
>
> Thank you for your insights.
>
>
>
> Again, I am thinking outside of the box, so to do so, I have to
build my own
> box :-)
>
>
>
> I am using hard drive bearings, so they are free for me, so nothing
on the
> cost, and they last a LONG time.
>
>
>
> The reason I am going thru such trouble is my device does not have much
> torque, this being said, I have run this device off of two batteries
>
> for well over 2 weeks time without recharging. All I am
attempting to do
> is to take advantage of the mechanical force the device gives.
>
>
>
> Right now, I have it setup with the electricity flowing thru the
hard drive
> bearings. ( Took me all day Saturday to make the coils, make a delta
> setup with the coils
>
> and make all of the connections within the PVC with the bridge diodes
> inside. I cannot yet say how well this is working, as I need to
work out a
> few bugs..
>
>
>
> If this does not work, I figure, it is very easy to go back to the other
> way, I have so far turned the wheel a few times and it did indeed get
> current thru the bearings, but much more work I will need to do in
order to
> clean up my setup, and see if I can improve it to have less work
involved in
> setting up.
>
>
>
> It just seems to me that the shaft will be easier to turn, if there
is less
> weight of the magnets to turn, and I am willing to put extra effort to
> explore this possibility.
>
>
>
> My setup will stay indoors and has to be monitored anyway, I do
think in
> time, I will find better methods of getting the electricity out (
perhaps
> transmit wirelessly a Tesla coil or a spark gap? ( I guess I love
> thinking outside of the box, even it it does mean I do get very lost at
> times.
>
>
>
> I want to thank you for pointing out the systems problems. It is not
> practical for a windmill ( something you have to pull down out of
the air
> everyday ) , but I think it is good for a hobby.
>
>
>
>
>
> I do want to say a BIG THANK YOU to whoever put together the
directions in
> the PDF found on this group of building the coils. They are very very
> well done and even I can follow them :-)
>
>
>
>
>
>
>
>
>
>
>
>
>
> ------------------------
> You really are a glutton for maintenance! Bearings, which are not
designed
> for current flows, have two problems as brush systems.
>
> 1.) DC current through bearings results in metal transfer from the (-)
> negative side to the (+) positive side as well as significant heat loads
> ()which reduces life.)
>
> 2.) Bearings tend to be hydrostatic devices which "fly" on a microscopic
bearing sets
> are pretty easy to buy, but they are expensive and difficult to use.
>
> Why look for trouble?
>
>
>
>
> --
> David G. LeVine
> Nashua, NH 03060
>

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• Yikes. is this overunity/perpetual motion stuff you re talking? If so good luck and I feel sorry for you. If not forgive me.. Lots of folks wanting to think
Message 9 of 12 , Feb 3, 2008
Yikes. is this overunity/perpetual motion stuff you're talking? If
so good luck and I feel sorry for you. If not forgive me..

Lots of folks wanting to think 'outside the box' these days. Not too
many willing to do the research to find out whats actually in it to
begin with though. Damned shame.

--- In axialflux@yahoogroups.com, "Mart Hale" <halemart@...> wrote:
>
> Thank you for your insights.
>
>
>
> Again, I am thinking outside of the box, so to do so, I have to
build my own
> box :-)
>
>
>
> I am using hard drive bearings, so they are free for me, so nothing
on the
> cost, and they last a LONG time.
>
>
>
> The reason I am going thru such trouble is my device does not have much
> torque, this being said, I have run this device off of two batteries
>
> for well over 2 weeks time without recharging. All I am
attempting to do
> is to take advantage of the mechanical force the device gives.
>
>
>
> Right now, I have it setup with the electricity flowing thru the
hard drive
> bearings. ( Took me all day Saturday to make the coils, make a delta
> setup with the coils
>
> and make all of the connections within the PVC with the bridge diodes
> inside. I cannot yet say how well this is working, as I need to
work out a
> few bugs..
>
>
>
> If this does not work, I figure, it is very easy to go back to the other
> way, I have so far turned the wheel a few times and it did indeed get
> current thru the bearings, but much more work I will need to do in
order to
> clean up my setup, and see if I can improve it to have less work
involved in
> setting up.
>
>
>
> It just seems to me that the shaft will be easier to turn, if there
is less
> weight of the magnets to turn, and I am willing to put extra effort to
> explore this possibility.
>
>
>
> My setup will stay indoors and has to be monitored anyway, I do
think in
> time, I will find better methods of getting the electricity out (
perhaps
> transmit wirelessly a Tesla coil or a spark gap? ( I guess I love
> thinking outside of the box, even it it does mean I do get very lost at
> times.
>
>
>
> I want to thank you for pointing out the systems problems. It is not
> practical for a windmill ( something you have to pull down out of
the air
> everyday ) , but I think it is good for a hobby.
>
>
>
>
>
> I do want to say a BIG THANK YOU to whoever put together the
directions in
> the PDF found on this group of building the coils. They are very very
> well done and even I can follow them :-)
>
>
>
>
>
>
>
>
>
>
>
>
>
> ------------------------
> You really are a glutton for maintenance! Bearings, which are not
designed
> for current flows, have two problems as brush systems.
>
> 1.) DC current through bearings results in metal transfer from the (-)
> negative side to the (+) positive side as well as significant heat loads
> ()which reduces life.)
>
> 2.) Bearings tend to be hydrostatic devices which "fly" on a microscopic
bearing sets
> are pretty easy to buy, but they are expensive and difficult to use.
>
> Why look for trouble?
>
>
>
>
> --
> David G. LeVine
> Nashua, NH 03060
>
• ... You are welcome. ... Not a bad way to go. ... They may not do so with large currents running through them, but I can t figure a cheaper dollars per watt
Message 10 of 12 , Feb 28, 2008
Mart Hale wrote:
>
> Thank you for your insights.
>
You are welcome.
>
>
>
> Again, I am thinking outside of the box, so to do so, I have to build
> my own box J
>

Not a bad way to go.
>
>
>
> I am using hard drive bearings, so they are free for me, so nothing on
> the cost, and they last a LONG time.
>

They may not do so with large currents running through them, but I can't
figure a cheaper dollars per watt approach.

Just as a thought, a "cup" core looks like a can with a post in the
middle. The coil is wound around the middle post. Put two together,
open face to open face, with a small gap and it becomes a transformer.
You can send AC through it with no maintenance as long as the gap
remains clean.

--
David G. LeVine
Nashua, NH 03060
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