Non electronic speed controller

[JB]

Running an Air Boat ( single 8" x 6 prop) and to get the full blast of power
I am using 2 x 7.2v battery packs which at full charge gives up to 16.8v.
It goes like a bomb but never reaches the full potential as fuses blow.
Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
blowing the fuse.

As electronic speed controllers are expensive and I don't wish to blow mine,
does anyone know of an electromechanical controller (not a bobs board) which
would cope with the power.
Alternatively, any plans for a suitable one.

Hoping to really Zoooooom

JB

[RS]

why a fuse? never seen a mechanical speed control with a fuse. Just run 13
or lower gauge wire and dump the fuse.
"JB" <postmaster@[127.0.0.1]> wrote in message
news:MkWad.157$Dk7.149@newsfe5-gui.ntli.net...
> Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
power
> I am using 2 x 7.2v battery packs which at full charge gives up to 16.8v.
> It goes like a bomb but never reaches the full potential as fuses blow.
> Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
> blowing the fuse.
>
> As electronic speed controllers are expensive and I don't wish to blow
mine,
> does anyone know of an electromechanical controller (not a bobs board)
which
> would cope with the power.
> Alternatively, any plans for a suitable one.
>
> Hoping to really Zoooooom
>
> JB
>
>

[Kevin R]

run it through a couple of switches set it to give 7.2 with the batteries in
parallel and then full throttle run the batteries in series and ditch the
fuse
Kevin
"JB" <postmaster@[127.0.0.1]> wrote in message
news:MkWad.157$Dk7.149@newsfe5-gui.ntli.net...
> Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
> power I am using 2 x 7.2v battery packs which at full charge gives up to
> 16.8v.
> It goes like a bomb but never reaches the full potential as fuses blow.
> Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
> blowing the fuse.
>
> As electronic speed controllers are expensive and I don't wish to blow
> mine, does anyone know of an electromechanical controller (not a bobs
> board) which would cope with the power.
> Alternatively, any plans for a suitable one.
>
> Hoping to really Zoooooom
>
> JB
>

[John Mianowski]

http://www.jkmiller.net/ntxbg/pgOnTheWays/pgMotorSpeed.html

JM

On Tue, 12 Oct 2004 19:34:04 GMT, "JB" <postmaster@[127.0.0.1]> wrote:

>Running an Air Boat ( single 8" x 6 prop) and to get the full blast of power
>I am using 2 x 7.2v battery packs which at full charge gives up to 16.8v.
>It goes like a bomb but never reaches the full potential as fuses blow.
>Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
>blowing the fuse.
>
>As electronic speed controllers are expensive and I don't wish to blow mine,
>does anyone know of an electromechanical controller (not a bobs board) which
>would cope with the power.
>Alternatively, any plans for a suitable one.
>
>Hoping to really Zoooooom
>
>JB
>

[Kevin R]

Forget about the varible resistor unless you have a high wattage one lying
about as 30amp at any resistance is going to get very hot and burn out
quicker than a fuse
Kevin
"John Mianowski" <spamfree@lenoardonline.net> wrote in message
news:rpmom0d8cvlec070crj9eu3g0fk1gl2iuo@4ax.com...
> http://www.jkmiller.net/ntxbg/pgOnTheWays/pgMotorSpeed.html
>
> JM
>
> On Tue, 12 Oct 2004 19:34:04 GMT, "JB" <postmaster@[127.0.0.1]> wrote:
>
>>Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
>>power
>>I am using 2 x 7.2v battery packs which at full charge gives up to 16.8v.
>>It goes like a bomb but never reaches the full potential as fuses blow.
>>Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
>>blowing the fuse.
>>
>>As electronic speed controllers are expensive and I don't wish to blow
>>mine,
>>does anyone know of an electromechanical controller (not a bobs board)
>>which
>>would cope with the power.
>>Alternatively, any plans for a suitable one.
>>
>>Hoping to really Zoooooom
>>
>>JB
>>
>

[JB]

Kevin R

I do not get the speed required at 7.2v (8.4 full). At 14.4+ it goes fast
but as I said never reaches full power.
I do not think my expensive speed controller would cope with the added
amperage.

JB
"Kevin R" <dontemailme@ntlworld.com> wrote in message
news:hiYad.2276$4y4.544@newsfe3-win.ntli.net...
> run it through a couple of switches set it to give 7.2 with the batteries
> in parallel and then full throttle run the batteries in series and ditch
> the fuse
> Kevin
> "JB" <postmaster@[127.0.0.1]> wrote in message
> news:MkWad.157$Dk7.149@newsfe5-gui.ntli.net...
>> Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
>> power I am using 2 x 7.2v battery packs which at full charge gives up to
>> 16.8v.
>> It goes like a bomb but never reaches the full potential as fuses blow.
>> Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
>> blowing the fuse.
>>
>> As electronic speed controllers are expensive and I don't wish to blow
>> mine, does anyone know of an electromechanical controller (not a bobs
>> board) which would cope with the power.
>> Alternatively, any plans for a suitable one.
>>
>> Hoping to really Zoooooom
>>
>> JB
>>
>
>

[The Grey Goose]

JB wrote:
> Kevin R
>
> I do not get the speed required at 7.2v (8.4 full). At 14.4+ it goes fast
> but as I said never reaches full power.
> I do not think my expensive speed controller would cope with the added
> amperage.
>
> JB
> "Kevin R" <dontemailme@ntlworld.com> wrote in message
> news:hiYad.2276$4y4.544@newsfe3-win.ntli.net...
>
>>run it through a couple of switches set it to give 7.2 with the batteries
>>in parallel and then full throttle run the batteries in series and ditch
>>the fuse
>>Kevin
>>"JB" <postmaster@[127.0.0.1]> wrote in message
>>news:MkWad.157$Dk7.149@newsfe5-gui.ntli.net...
>>
>>>Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
>>>power I am using 2 x 7.2v battery packs which at full charge gives up to
>>>16.8v.
>>>It goes like a bomb but never reaches the full potential as fuses blow.
>>>Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
>>>blowing the fuse.
>>>
>>>As electronic speed controllers are expensive and I don't wish to blow
>>>mine, does anyone know of an electromechanical controller (not a bobs
>>>board) which would cope with the power.
>>>Alternatively, any plans for a suitable one.
>>>
>>>Hoping to really Zoooooom
>>>
>>>JB
>>>
>>
>>
>
>

I race in the SWAMBC fast electric powerboat
series here in the UK and our formula 4 guys use
AStec 100 amp high frequency speed controllers
these can handle 12 cells comfortably I assume
that the 16.8 volts that you record are the
product of surface charge which disappears very
quickly so I'm unsure what you have against
electronic speed control,if your controller is up
to it there really shouldn't be any problems

HTH

--

The Goose

Trolls & spammers
Nuke them till they glow
And shoot them in the Dark

[JB]

There must be some way of utilising the power generated to give maximum
speed.
There is surely an answer somewhere.
I agree about the heat generation but I have the space and the weight
capacity to fit a cooling fan.
John Mianowski's solution would not give me the control required but is a
very interesting concept for slower boats.

Thanks

JB


"Kevin R" <dontemailme@ntlworld.com> wrote in message
news:I%5bd.28$4G3.14@newsfe3-win.ntli.net...
> Forget about the varible resistor unless you have a high wattage one lying
> about as 30amp at any resistance is going to get very hot and burn out
> quicker than a fuse
> Kevin
> "John Mianowski" <spamfree@lenoardonline.net> wrote in message
> news:rpmom0d8cvlec070crj9eu3g0fk1gl2iuo@4ax.com...
>> http://www.jkmiller.net/ntxbg/pgOnTheWays/pgMotorSpeed.html
>>
>> JM
>>
>> On Tue, 12 Oct 2004 19:34:04 GMT, "JB" <postmaster@[127.0.0.1]> wrote:
>>
>>>Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
>>>power
>>>I am using 2 x 7.2v battery packs which at full charge gives up to 16.8v.
>>>It goes like a bomb but never reaches the full potential as fuses blow.
>>>Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
>>>blowing the fuse.
>>>
>>>As electronic speed controllers are expensive and I don't wish to blow
>>>mine,
>>>does anyone know of an electromechanical controller (not a bobs board)
>>>which
>>>would cope with the power.
>>>Alternatively, any plans for a suitable one.
>>>
>>>Hoping to really Zoooooom
>>>
>>>JB
>>>
>>
>
>

[Kevin R]

Maximum speed needs no resistance connect the motor directly to the
batteries with a heavy duty switch for control and that will cut out a most
of the losses and it will give you the best speed if you want some sort of
control and to be honest do you really need fine control of an air boat they
always run flat out normally, if you do buy a FET based speed controller
40amps + are avalible
Kevin
"JB" <postmaster@[127.0.0.1]> wrote in message
news:XOcbd.493$B63.388@newsfe5-win.ntli.net...
> There must be some way of utilising the power generated to give maximum
> speed.
> There is surely an answer somewhere.
> I agree about the heat generation but I have the space and the weight
> capacity to fit a cooling fan.
> John Mianowski's solution would not give me the control required but is a
> very interesting concept for slower boats.
>
> Thanks
>
> JB
>
>
> "Kevin R" <dontemailme@ntlworld.com> wrote in message
> news:I%5bd.28$4G3.14@newsfe3-win.ntli.net...
>> Forget about the varible resistor unless you have a high wattage one
>> lying about as 30amp at any resistance is going to get very hot and burn
>> out quicker than a fuse
>> Kevin
>> "John Mianowski" <spamfree@lenoardonline.net> wrote in message
>> news:rpmom0d8cvlec070crj9eu3g0fk1gl2iuo@4ax.com...
>>> http://www.jkmiller.net/ntxbg/pgOnTheWays/pgMotorSpeed.html
>>>
>>> JM
>>>
>>> On Tue, 12 Oct 2004 19:34:04 GMT, "JB" <postmaster@[127.0.0.1]> wrote:
>>>
>>>>Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
>>>>power
>>>>I am using 2 x 7.2v battery packs which at full charge gives up to
>>>>16.8v.
>>>>It goes like a bomb but never reaches the full potential as fuses blow.
>>>>Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
>>>>blowing the fuse.
>>>>
>>>>As electronic speed controllers are expensive and I don't wish to blow
>>>>mine,
>>>>does anyone know of an electromechanical controller (not a bobs board)
>>>>which
>>>>would cope with the power.
>>>>Alternatively, any plans for a suitable one.
>>>>
>>>>Hoping to really Zoooooom
>>>>
>>>>JB
>>>>
>>>
>>
>>
>
>

[RS]

if it won't handle 30amps, it is not very good. Get a Astroflight 207, it
will handle 60amps quite well.

How expensive was it? An Astroflight 207D handles 60amps continuous and 6 to
40 cells at $89.

http://www.astroflight.com/e/env/0001shtQU6xYrncLTs908Y2/store/store-Controls.html?link=/store/store-type-tem.html&item=products:af-207dmaybe .

"JB" <postmaster@[127.0.0.1]> wrote in message
news:X9cbd.389$p53.247@newsfe6-win.ntli.net...
> Kevin R
>
> I do not get the speed required at 7.2v (8.4 full). At 14.4+ it goes fast
> but as I said never reaches full power.
> I do not think my expensive speed controller would cope with the added
> amperage.
>
> JB
> "Kevin R" <dontemailme@ntlworld.com> wrote in message
> news:hiYad.2276$4y4.544@newsfe3-win.ntli.net...
> > run it through a couple of switches set it to give 7.2 with the
batteries
> > in parallel and then full throttle run the batteries in series and ditch
> > the fuse
> > Kevin
> > "JB" <postmaster@[127.0.0.1]> wrote in message
> > news:MkWad.157$Dk7.149@newsfe5-gui.ntli.net...
> >> Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
> >> power I am using 2 x 7.2v battery packs which at full charge gives up
to
> >> 16.8v.
> >> It goes like a bomb but never reaches the full potential as fuses blow.
> >> Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
> >> blowing the fuse.
> >>
> >> As electronic speed controllers are expensive and I don't wish to blow
> >> mine, does anyone know of an electromechanical controller (not a bobs
> >> board) which would cope with the power.
> >> Alternatively, any plans for a suitable one.
> >>
> >> Hoping to really Zoooooom
> >>
> >> JB
> >>
> >
> >
>
>

[JB]

Kevin, you have the advantage - what is a FET based speed controller?
JB

"Kevin R" <dontemailme@ntlworld.com> wrote in message
news:FBfbd.482$4G3.21@newsfe3-win.ntli.net...
> Maximum speed needs no resistance connect the motor directly to the
> batteries with a heavy duty switch for control and that will cut out a
> most of the losses and it will give you the best speed if you want some
> sort of control and to be honest do you really need fine control of an air
> boat they always run flat out normally, if you do buy a FET based speed
> controller 40amps + are avalible
> Kevin
> "JB" <postmaster@[127.0.0.1]> wrote in message
> news:XOcbd.493$B63.388@newsfe5-win.ntli.net...
>> There must be some way of utilising the power generated to give maximum
>> speed.
>> There is surely an answer somewhere.
>> I agree about the heat generation but I have the space and the weight
>> capacity to fit a cooling fan.
>> John Mianowski's solution would not give me the control required but is a
>> very interesting concept for slower boats.
>>
>> Thanks
>>
>> JB
>>
>>
>> "Kevin R" <dontemailme@ntlworld.com> wrote in message
>> news:I%5bd.28$4G3.14@newsfe3-win.ntli.net...
>>> Forget about the varible resistor unless you have a high wattage one
>>> lying about as 30amp at any resistance is going to get very hot and
>>> burn out quicker than a fuse
>>> Kevin
>>> "John Mianowski" <spamfree@lenoardonline.net> wrote in message
>>> news:rpmom0d8cvlec070crj9eu3g0fk1gl2iuo@4ax.com...
>>>> http://www.jkmiller.net/ntxbg/pgOnTheWays/pgMotorSpeed.html
>>>>
>>>> JM
>>>>
>>>> On Tue, 12 Oct 2004 19:34:04 GMT, "JB" <postmaster@[127.0.0.1]> wrote:
>>>>
>>>>>Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
>>>>>power
>>>>>I am using 2 x 7.2v battery packs which at full charge gives up to
>>>>>16.8v.
>>>>>It goes like a bomb but never reaches the full potential as fuses blow.
>>>>>Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
>>>>>blowing the fuse.
>>>>>
>>>>>As electronic speed controllers are expensive and I don't wish to blow
>>>>>mine,
>>>>>does anyone know of an electromechanical controller (not a bobs board)
>>>>>which
>>>>>would cope with the power.
>>>>>Alternatively, any plans for a suitable one.
>>>>>
>>>>>Hoping to really Zoooooom
>>>>>
>>>>>JB
>>>>>
>>>>
>>>
>>>
>>
>>
>
>

[Kevin R]

just a type of transistor in one of the modern speed controllers rather than
a old style speed controller any of the small modern types will have a low
insertion loss http://www.ripmax.com/FS_Access_XtraElectronics.html this
sort of controller rather than one with a big bulky heatsink most you will
have trouble in destroying as they cut out if over loaded or overheated just
go for an aircraft one
Kevin

"JB" <postmaster@[127.0.0.1]> wrote in message
news:Zctbd.50$Nc2.48@newsfe5-win.ntli.net...
> Kevin, you have the advantage - what is a FET based speed controller?
> JB
>
> "Kevin R" <dontemailme@ntlworld.com> wrote in message
> news:FBfbd.482$4G3.21@newsfe3-win.ntli.net...
>> Maximum speed needs no resistance connect the motor directly to the
>> batteries with a heavy duty switch for control and that will cut out a
>> most of the losses and it will give you the best speed if you want some
>> sort of control and to be honest do you really need fine control of an
>> air boat they always run flat out normally, if you do buy a FET based
>> speed controller 40amps + are avalible
>> Kevin
>> "JB" <postmaster@[127.0.0.1]> wrote in message
>> news:XOcbd.493$B63.388@newsfe5-win.ntli.net...
>>> There must be some way of utilising the power generated to give maximum
>>> speed.
>>> There is surely an answer somewhere.
>>> I agree about the heat generation but I have the space and the weight
>>> capacity to fit a cooling fan.
>>> John Mianowski's solution would not give me the control required but is
>>> a very interesting concept for slower boats.
>>>
>>> Thanks
>>>
>>> JB
>>>
>>>
>>> "Kevin R" <dontemailme@ntlworld.com> wrote in message
>>> news:I%5bd.28$4G3.14@newsfe3-win.ntli.net...
>>>> Forget about the varible resistor unless you have a high wattage one
>>>> lying about as 30amp at any resistance is going to get very hot and
>>>> burn out quicker than a fuse
>>>> Kevin
>>>> "John Mianowski" <spamfree@lenoardonline.net> wrote in message
>>>> news:rpmom0d8cvlec070crj9eu3g0fk1gl2iuo@4ax.com...
>>>>> http://www.jkmiller.net/ntxbg/pgOnTheWays/pgMotorSpeed.html
>>>>>
>>>>> JM
>>>>>
>>>>> On Tue, 12 Oct 2004 19:34:04 GMT, "JB" <postmaster@[127.0.0.1]> wrote:
>>>>>
>>>>>>Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
>>>>>>power
>>>>>>I am using 2 x 7.2v battery packs which at full charge gives up to
>>>>>>16.8v.
>>>>>>It goes like a bomb but never reaches the full potential as fuses
>>>>>>blow.
>>>>>>Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and
>>>>>>still
>>>>>>blowing the fuse.
>>>>>>
>>>>>>As electronic speed controllers are expensive and I don't wish to blow
>>>>>>mine,
>>>>>>does anyone know of an electromechanical controller (not a bobs board)
>>>>>>which
>>>>>>would cope with the power.
>>>>>>Alternatively, any plans for a suitable one.
>>>>>>
>>>>>>Hoping to really Zoooooom
>>>>>>
>>>>>>JB
>>>>>>
>>>>>
>>>>
>>>>
>>>
>>>
>>
>>
>
>

[JB]

K
I am currently using the Ripmax P-Xtra Volcano which is primarily a Car
Controller with a heat cut-off and in theory should not burn out at the
maximum power output that I can give it.
Having said that, the aircraft one which I had installed initially (forward
only) went up in a spectacular puff of smoke in the middle of the pond when
it was going flat out.( no fuse fitted at that stage)
Would the P-Xtra Volcano be any better?
Costly if it isn't

JB


"Kevin R" <dontemailme@ntlworld.com> wrote in message
news:wcvbd.55$wy5.5@newsfe2-gui.ntli.net...
> just a type of transistor in one of the modern speed controllers rather
> than a old style speed controller any of the small modern types will have
> a low insertion loss http://www.ripmax.com/FS_Access_XtraElectronics.html
> this sort of controller rather than one with a big bulky heatsink most you
> will have trouble in destroying as they cut out if over loaded or
> overheated just go for an aircraft one
> Kevin
>
> "JB" <postmaster@[127.0.0.1]> wrote in message
> news:Zctbd.50$Nc2.48@newsfe5-win.ntli.net...
>> Kevin, you have the advantage - what is a FET based speed controller?
>> JB
>>
>> "Kevin R" <dontemailme@ntlworld.com> wrote in message
>> news:FBfbd.482$4G3.21@newsfe3-win.ntli.net...
>>> Maximum speed needs no resistance connect the motor directly to the
>>> batteries with a heavy duty switch for control and that will cut out a
>>> most of the losses and it will give you the best speed if you want some
>>> sort of control and to be honest do you really need fine control of an
>>> air boat they always run flat out normally, if you do buy a FET based
>>> speed controller 40amps + are avalible
>>> Kevin
>>> "JB" <postmaster@[127.0.0.1]> wrote in message
>>> news:XOcbd.493$B63.388@newsfe5-win.ntli.net...
>>>> There must be some way of utilising the power generated to give maximum
>>>> speed.
>>>> There is surely an answer somewhere.
>>>> I agree about the heat generation but I have the space and the weight
>>>> capacity to fit a cooling fan.
>>>> John Mianowski's solution would not give me the control required but is
>>>> a very interesting concept for slower boats.
>>>>
>>>> Thanks
>>>>
>>>> JB
>>>>
>>>>
>>>> "Kevin R" <dontemailme@ntlworld.com> wrote in message
>>>> news:I%5bd.28$4G3.14@newsfe3-win.ntli.net...
>>>>> Forget about the varible resistor unless you have a high wattage one
>>>>> lying about as 30amp at any resistance is going to get very hot and
>>>>> burn out quicker than a fuse
>>>>> Kevin
>>>>> "John Mianowski" <spamfree@lenoardonline.net> wrote in message
>>>>> news:rpmom0d8cvlec070crj9eu3g0fk1gl2iuo@4ax.com...
>>>>>> http://www.jkmiller.net/ntxbg/pgOnTheWays/pgMotorSpeed.html
>>>>>>
>>>>>> JM
>>>>>>
>>>>>> On Tue, 12 Oct 2004 19:34:04 GMT, "JB" <postmaster@[127.0.0.1]>
>>>>>> wrote:
>>>>>>
>>>>>>>Running an Air Boat ( single 8" x 6 prop) and to get the full blast
>>>>>>>of power
>>>>>>>I am using 2 x 7.2v battery packs which at full charge gives up to
>>>>>>>16.8v.
>>>>>>>It goes like a bomb but never reaches the full potential as fuses
>>>>>>>blow.
>>>>>>>Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and
>>>>>>>still
>>>>>>>blowing the fuse.
>>>>>>>
>>>>>>>As electronic speed controllers are expensive and I don't wish to
>>>>>>>blow mine,
>>>>>>>does anyone know of an electromechanical controller (not a bobs
>>>>>>>board) which
>>>>>>>would cope with the power.
>>>>>>>Alternatively, any plans for a suitable one.
>>>>>>>
>>>>>>>Hoping to really Zoooooom
>>>>>>>
>>>>>>>JB
>>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>
>>>
>>
>>
>
>

[Vaughn]

If you want a little more in depth description try this link:

http://burks.brighton.ac.uk/burks/foldoc/12/42.htm

And here is one on the most commonly used JFET:

http://www.st-andrews.ac.uk/~www_pa/Scots_Guide/info/comp/active/jfet/jfet.htm

Plus I like it as it comes in colour ;-)

All the best Vaughn


"JB" <postmaster@[127.0.0.1]> wrote in message
news:Zctbd.50$Nc2.48@newsfe5-win.ntli.net...
> Kevin, you have the advantage - what is a FET based speed controller?
> JB
>
> "Kevin R" <dontemailme@ntlworld.com> wrote in message
> news:FBfbd.482$4G3.21@newsfe3-win.ntli.net...
> > Maximum speed needs no resistance connect the motor directly to the
> > batteries with a heavy duty switch for control and that will cut out a
> > most of the losses and it will give you the best speed if you want some
> > sort of control and to be honest do you really need fine control of an
air
> > boat they always run flat out normally, if you do buy a FET based speed
> > controller 40amps + are avalible
> > Kevin
> > "JB" <postmaster@[127.0.0.1]> wrote in message
> > news:XOcbd.493$B63.388@newsfe5-win.ntli.net...
> >> There must be some way of utilising the power generated to give maximum
> >> speed.
> >> There is surely an answer somewhere.
> >> I agree about the heat generation but I have the space and the weight
> >> capacity to fit a cooling fan.
> >> John Mianowski's solution would not give me the control required but is
a
> >> very interesting concept for slower boats.
> >>
> >> Thanks
> >>
> >> JB
> >>
> >>
> >> "Kevin R" <dontemailme@ntlworld.com> wrote in message
> >> news:I%5bd.28$4G3.14@newsfe3-win.ntli.net...
> >>> Forget about the varible resistor unless you have a high wattage one
> >>> lying about as 30amp at any resistance is going to get very hot and
> >>> burn out quicker than a fuse
> >>> Kevin
> >>> "John Mianowski" <spamfree@lenoardonline.net> wrote in message
> >>> news:rpmom0d8cvlec070crj9eu3g0fk1gl2iuo@4ax.com...
> >>>> http://www.jkmiller.net/ntxbg/pgOnTheWays/pgMotorSpeed.html
> >>>>
> >>>> JM
> >>>>
> >>>> On Tue, 12 Oct 2004 19:34:04 GMT, "JB" <postmaster@[127.0.0.1]>
wrote:
> >>>>
> >>>>>Running an Air Boat ( single 8" x 6 prop) and to get the full blast
of
> >>>>>power
> >>>>>I am using 2 x 7.2v battery packs which at full charge gives up to
> >>>>>16.8v.
> >>>>>It goes like a bomb but never reaches the full potential as fuses
blow.
> >>>>>Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and
still
> >>>>>blowing the fuse.
> >>>>>
> >>>>>As electronic speed controllers are expensive and I don't wish to
blow
> >>>>>mine,
> >>>>>does anyone know of an electromechanical controller (not a bobs
board)
> >>>>>which
> >>>>>would cope with the power.
> >>>>>Alternatively, any plans for a suitable one.
> >>>>>
> >>>>>Hoping to really Zoooooom
> >>>>>
> >>>>>JB
> >>>>>
> >>>>
> >>>
> >>>
> >>
> >>
> >
> >
>
>

[Boat Hull Maker]

FET means Field Effect Transistor. Can treat it as a voltage controlled
current source.

Please concern the maximum power of the motor instead of maximum speed.
Higher speed, less running time. Running at maximum power of the motor is
compromise btw speed and power consumption.

"JB" <postmaster@[127.0.0.1]> ¼¶¼g©ó¶l¥ó
news:Zctbd.50$Nc2.48@newsfe5-win.ntli.net...
> Kevin, you have the advantage - what is a FET based speed controller?
> JB
>
> "Kevin R" <dontemailme@ntlworld.com> wrote in message
> news:FBfbd.482$4G3.21@newsfe3-win.ntli.net...
> > Maximum speed needs no resistance connect the motor directly to the
> > batteries with a heavy duty switch for control and that will cut out a
> > most of the losses and it will give you the best speed if you want some

[JB]

Starting to construct a basic controlled based on your post. Modifying
slightly on lower the lower voltage to give some control at slow speeds and
in a reverse (just in case I have to!) mode

JB

"John Mianowski" <spamfree@lenoardonline.net> wrote in message
news:rpmom0d8cvlec070crj9eu3g0fk1gl2iuo@4ax.com...
> http://www.jkmiller.net/ntxbg/pgOnTheWays/pgMotorSpeed.html
>
> JM
>
> On Tue, 12 Oct 2004 19:34:04 GMT, "JB" <postmaster@[127.0.0.1]> wrote:
>
>>Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
>>power
>>I am using 2 x 7.2v battery packs which at full charge gives up to 16.8v.
>>It goes like a bomb but never reaches the full potential as fuses blow.
>>Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
>>blowing the fuse.
>>
>>As electronic speed controllers are expensive and I don't wish to blow
>>mine,
>>does anyone know of an electromechanical controller (not a bobs board)
>>which
>>would cope with the power.
>>Alternatively, any plans for a suitable one.
>>
>>Hoping to really Zoooooom
>>
>>JB
>>
>

[JB]

I am currently making up a basic controller as suggested by John Mianowsk in
his post of 12 Oct
with one or two modifications to give slow speed control.
news:rpmom0d8cvlec070crj9eu3g0fk1gl2iuo@4ax.com...
We'll see how it works in due course.

JB
"Boat Hull Maker" <pay@btorcboat.com> wrote in message
news:41730772$1_1@rain.i-cable.com...
> FET means Field Effect Transistor. Can treat it as a voltage controlled
> current source.
>
> Please concern the maximum power of the motor instead of maximum speed.
> Higher speed, less running time. Running at maximum power of the motor is
> compromise btw speed and power consumption.
>
> "JB" <postmaster@[127.0.0.1]> ¼¶¼g©ó¶l¥ó
> news:Zctbd.50$Nc2.48@newsfe5-win.ntli.net...
>> Kevin, you have the advantage - what is a FET based speed controller?
>> JB
>>
>> "Kevin R" <dontemailme@ntlworld.com> wrote in message
>> news:FBfbd.482$4G3.21@newsfe3-win.ntli.net...
>> > Maximum speed needs no resistance connect the motor directly to the
>> > batteries with a heavy duty switch for control and that will cut out a
>> > most of the losses and it will give you the best speed if you want some
>
>
>

[John Mianowski]

I'm curious about modifications. Please post details when you're
done.

JM

On Mon, 18 Oct 2004 11:22:57 GMT, "JB" <JB@another.place> wrote:

>Starting to construct a basic controlled based on your post. Modifying
>slightly on lower the lower voltage to give some control at slow speeds and
>in a reverse (just in case I have to!) mode
>
>JB
>
>"John Mianowski" <spamfree@lenoardonline.net> wrote in message
>news:rpmom0d8cvlec070crj9eu3g0fk1gl2iuo@4ax.com...
>> http://www.jkmiller.net/ntxbg/pgOnTheWays/pgMotorSpeed.html
>>
>> JM
>>
>> On Tue, 12 Oct 2004 19:34:04 GMT, "JB" <postmaster@[127.0.0.1]> wrote:
>>
>>>Running an Air Boat ( single 8" x 6 prop) and to get the full blast of
>>>power
>>>I am using 2 x 7.2v battery packs which at full charge gives up to 16.8v.
>>>It goes like a bomb but never reaches the full potential as fuses blow.
>>>Started a 10amp progressed thro' 15, 20, 25 and finally 30amp and still
>>>blowing the fuse.
>>>
>>>As electronic speed controllers are expensive and I don't wish to blow
>>>mine,
>>>does anyone know of an electromechanical controller (not a bobs board)
>>>which
>>>would cope with the power.
>>>Alternatively, any plans for a suitable one.
>>>
>>>Hoping to really Zoooooom
>>>
>>>JB
>>>
>>
>