Rotor speed

[Jacko]

Hi all !

I was just wondering....... how do you "guage" how fast your rotor speed is
in a hover ?

Is it all done puely by sound ? and experience ?

I read somewhere about rotor speeds...... should be a certain rpm.... but
how do you distinguish that speed ? Is it a case of listening and just
telling that the engine is running smoothly without screaming ?

Its a Kyosho Nexus 30 with an MDS 38 engine.

Hope you can advise ?

Jacko

[david]

I used to run a Nexy with a 39 in it...and trust me, when them blades is too
fast they let ya know!! Sounds awful!

David
"Jacko" <jacko@home.co.uk> wrote in message
news:bitcni$6t1$3@newsg2.svr.pol.co.uk...
> Hi all !
>
> I was just wondering....... how do you "guage" how fast your rotor speed
is
> in a hover ?
>
> Is it all done puely by sound ? and experience ?
>
> I read somewhere about rotor speeds...... should be a certain rpm.... but
> how do you distinguish that speed ? Is it a case of listening and just
> telling that the engine is running smoothly without screaming ?
>
> Its a Kyosho Nexus 30 with an MDS 38 engine.
>
> Hope you can advise ?
>
> Jacko
>
>

[Beav]

"Jacko" <jacko@home.co.uk> wrote in message
news:bitcni$6t1$3@newsg2.svr.pol.co.uk...
> Hi all !
>
> I was just wondering....... how do you "guage" how fast your rotor speed
is
> in a hover ?
>
> Is it all done puely by sound ? and experience ?

Usually yes, but you can buy tacho's that do it too.
>
> I read somewhere about rotor speeds...... should be a certain rpm.... but
> how do you distinguish that speed ? Is it a case of listening and just
> telling that the engine is running smoothly without screaming ?

Heli's either sound "happy" or they don't. I know it's not easy to describe
"happy", but if a heli's screaming it's bollocks off, you'll know about i:-)
and if it's revving too slowly, it'll not be happy when you try flying it.
It'll feel "soggy" and unresponsive.



--
Beav


Please note my E-mail address is "beavis dot original at ntlworld dot com"
(with the obvious changes)

Beavisland now lives at
www.beavisoriginal.co.uk

[TimJ]

"Jacko" <jacko@home.co.uk> wrote in message
news:bitcni$6t1$3@newsg2.svr.pol.co.uk...
> Hi all !
>
> I was just wondering....... how do you "guage" how fast your rotor speed
is
> in a hover ?
>
> Is it all done puely by sound ? and experience ?
>
> I read somewhere about rotor speeds...... should be a certain rpm.... but
> how do you distinguish that speed ? Is it a case of listening and just
> telling that the engine is running smoothly without screaming ?
>
> Its a Kyosho Nexus 30 with an MDS 38 engine.
>
> Hope you can advise ?
>
> Jacko
>

If you have the money you can always invest in an optical tachometer which
you can use to read the head speed on a heli, well you can't use it yourself
while your flying, but a mate or spouse could :) I have a Kyosho one which
works fine, but a warning, they are not cheap !! Your mate will be able to
tell you what your head speed is in hover and forward flight using one ..
Only reason I got one is for the heli club that I'm involved with were
"thinking" about getting one, after 3 more months of thinking about it I
just bought one :-) I think minature aircraft do one too,. Handy tool, lets
you see exactly what head spped your running.

Cheers

[MrBonk]

If you were going to spend any money, you'd be better off buying a governor
instead of a tach. Much more value for money IMHO. Dial up the speed you
want and go fly.

MrBonk
www.mrbonk.com


"TimJ" <timjatarachdotnetdotau> wrote in message
news:3f52f748$1@funnel.arach.net.au...
>
> "Jacko" <jacko@home.co.uk> wrote in message
> news:bitcni$6t1$3@newsg2.svr.pol.co.uk...
> > Hi all !
> >
> > I was just wondering....... how do you "guage" how fast your rotor speed
> is
> > in a hover ?
> >
> > Is it all done puely by sound ? and experience ?
> >
> > I read somewhere about rotor speeds...... should be a certain rpm....
but
> > how do you distinguish that speed ? Is it a case of listening and just
> > telling that the engine is running smoothly without screaming ?
> >
> > Its a Kyosho Nexus 30 with an MDS 38 engine.
> >
> > Hope you can advise ?
> >
> > Jacko
> >
>
> If you have the money you can always invest in an optical tachometer which
> you can use to read the head speed on a heli, well you can't use it
yourself
> while your flying, but a mate or spouse could :) I have a Kyosho one which
> works fine, but a warning, they are not cheap !! Your mate will be able to
> tell you what your head speed is in hover and forward flight using one ..
> Only reason I got one is for the heli club that I'm involved with were
> "thinking" about getting one, after 3 more months of thinking about it I
> just bought one :-) I think minature aircraft do one too,. Handy tool,
lets
> you see exactly what head spped your running.
>
> Cheers
>
>

[E. Hill]

You can build an optical tach for less than $75. (Velleman makes a kit. Use
it with a mounted optical switch.)

Eric

[Jacko]

Thanks for all the feedback guys !

I hadnt thought of an optical tacho - we have one at work.... but its a
handheld unit, and I cant imagine getting anyone to be stupid enough to get
close to the heli to use it !

I understand the fact that it becomes rather soggy if its under revving....
but I am a bit concerned because my last MDS engine seized whilst hovering -
even though the mixture was rich enough to generate some smoke.....

Thankfully it autorotated ok - but now I am paranoid that I was just running
it too fast !

Anyhows - I will see if I have better luck with the new MDS and I may bring
the optical tacho home and consider mounted the heli in a stand and running
it up - that'll give me some idea of what it would be hovering at - and I
can get used to the sound.

By the way - what should the rotor RPM be on a Nexus 30 with an MDS 38 in it
?

THANKS again for the advice !

Jacko
"E. Hill" <anybody@anywhere.com> wrote in message
news:FEN4b.4905$tw6.3979@newsread4.news.pas.earthl ink.net...
> You can build an optical tach for less than $75. (Velleman makes a kit.
Use
> it with a mounted optical switch.)
>
> Eric
>
>

[david]

Mine did between 1650 and 1800. Above 1800 and she screamed.

David
"Jacko" <jacko@home.co.uk> wrote in message
news:bj0b7k$gev$1@newsg4.svr.pol.co.uk...
> Thanks for all the feedback guys !
>
> I hadnt thought of an optical tacho - we have one at work.... but its a
> handheld unit, and I cant imagine getting anyone to be stupid enough to
get
> close to the heli to use it !
>
> I understand the fact that it becomes rather soggy if its under
revving....
> but I am a bit concerned because my last MDS engine seized whilst
hovering -
> even though the mixture was rich enough to generate some smoke.....
>
> Thankfully it autorotated ok - but now I am paranoid that I was just
running
> it too fast !
>
> Anyhows - I will see if I have better luck with the new MDS and I may
bring
> the optical tacho home and consider mounted the heli in a stand and
running
> it up - that'll give me some idea of what it would be hovering at - and I
> can get used to the sound.
>
> By the way - what should the rotor RPM be on a Nexus 30 with an MDS 38 in
it
> ?
>
> THANKS again for the advice !
>
> Jacko
> "E. Hill" <anybody@anywhere.com> wrote in message
> news:FEN4b.4905$tw6.3979@newsread4.news.pas.earthl ink.net...
> > You can build an optical tach for less than $75. (Velleman makes a kit.
> Use
> > it with a mounted optical switch.)
> >
> > Eric
> >
> >
>
>

[Jacko]

Thanks Dave........ I thought it was about 1800 rpm........

trouble is, now I can see me strapping a handheld optical tacho onto the
canopy pointing up at the blades !

Cheers !

Jacko
"david" <david_perry@btconnect.com> wrote in message
news:bj0hvq$rmp$1@hercules.btinternet.com...
> Mine did between 1650 and 1800. Above 1800 and she screamed.
>
> David
> "Jacko" <jacko@home.co.uk> wrote in message
> news:bj0b7k$gev$1@newsg4.svr.pol.co.uk...
> > Thanks for all the feedback guys !
> >
> > I hadnt thought of an optical tacho - we have one at work.... but its a
> > handheld unit, and I cant imagine getting anyone to be stupid enough to
> get
> > close to the heli to use it !
> >
> > I understand the fact that it becomes rather soggy if its under
> revving....
> > but I am a bit concerned because my last MDS engine seized whilst
> hovering -
> > even though the mixture was rich enough to generate some smoke.....
> >
> > Thankfully it autorotated ok - but now I am paranoid that I was just
> running
> > it too fast !
> >
> > Anyhows - I will see if I have better luck with the new MDS and I may
> bring
> > the optical tacho home and consider mounted the heli in a stand and
> running
> > it up - that'll give me some idea of what it would be hovering at - and
I
> > can get used to the sound.
> >
> > By the way - what should the rotor RPM be on a Nexus 30 with an MDS 38
in
> it
> > ?
> >
> > THANKS again for the advice !
> >
> > Jacko
> > "E. Hill" <anybody@anywhere.com> wrote in message
> > news:FEN4b.4905$tw6.3979@newsread4.news.pas.earthl ink.net...
> > > You can build an optical tach for less than $75. (Velleman makes a
kit.
> > Use
> > > it with a mounted optical switch.)
> > >
> > > Eric
> > >
> > >
> >
> >
>
>

[Chris Dugan]

There have been people in the past who have used cycle tacho's mounted on
the boom which are using a magnet in the main gear as the pickup for the
sensor. Cheap and cheerfull they usually keep the highest RPM and average
RPM after a flight and a few others (miles travelled, calories burned etc
not much use to us!)

If you do a search on Google's group archive you'll find the info.

Chris
"Jacko" <jacko@home.co.uk> wrote in message
news:bj2d1s$fke$1@newsg3.svr.pol.co.uk...
> Thanks Dave........ I thought it was about 1800 rpm........
>
> trouble is, now I can see me strapping a handheld optical tacho onto the
> canopy pointing up at the blades !
>
> Cheers !
>
> Jacko
> "david" <david_perry@btconnect.com> wrote in message
> news:bj0hvq$rmp$1@hercules.btinternet.com...
> > Mine did between 1650 and 1800. Above 1800 and she screamed.
> >
> > David
> > "Jacko" <jacko@home.co.uk> wrote in message
> > news:bj0b7k$gev$1@newsg4.svr.pol.co.uk...
> > > Thanks for all the feedback guys !
> > >
> > > I hadnt thought of an optical tacho - we have one at work.... but its
a
> > > handheld unit, and I cant imagine getting anyone to be stupid enough
to
> > get
> > > close to the heli to use it !
> > >
> > > I understand the fact that it becomes rather soggy if its under
> > revving....
> > > but I am a bit concerned because my last MDS engine seized whilst
> > hovering -
> > > even though the mixture was rich enough to generate some smoke.....
> > >
> > > Thankfully it autorotated ok - but now I am paranoid that I was just
> > running
> > > it too fast !
> > >
> > > Anyhows - I will see if I have better luck with the new MDS and I may
> > bring
> > > the optical tacho home and consider mounted the heli in a stand and
> > running
> > > it up - that'll give me some idea of what it would be hovering at -
and
> I
> > > can get used to the sound.
> > >
> > > By the way - what should the rotor RPM be on a Nexus 30 with an MDS 38
> in
> > it
> > > ?
> > >
> > > THANKS again for the advice !
> > >
> > > Jacko
> > > "E. Hill" <anybody@anywhere.com> wrote in message
> > > news:FEN4b.4905$tw6.3979@newsread4.news.pas.earthl ink.net...
> > > > You can build an optical tach for less than $75. (Velleman makes a
> kit.
> > > Use
> > > > it with a mounted optical switch.)
> > > >
> > > > Eric
> > > >
> > > >
> > >
> > >
> >
> >
>
>


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