REFLECTOR:V8 Vacuum system

Sat, 08 Nov 2003 10:36:51 -0600

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I think it's worth examining the whole issue and looking at why
things are the way they are ...
<... If you are not comfortable with solid state ...>
You might be well advised to examine what that (the discomfort
AND the technology) is all about.
<... RC Allen makes electric gyros ...>
.... have all the delicate, wearing, precessing moving parts of
the vacuum units ...
<... easier to design a redundant electrical system ...>
Actually, the alternators and batteries available these days are
so reliable that if either one is backed up, you have a
basically bulletproof system. Redundant batteries are an easy
and inexpensive solution. in the worst case scenario, an
alternator failure becomes a "blip" since you have an hour or an
hour or two to get to a suitable landing field and then repairs
are as close as the nearest NAPA store.

<... than redundant vacuum ...>
Let's remember the reason we HAVE [notoriously expensive and
unreliable] vacuum systems in the first place. In the olden
days (30s, 40s and 50s) generators were so unreliable, what with
high wear brushes, delicate stators and failure prone armature
windings, that they HAD to be backed up. We ended up with
magneto ignition and vacuum driven instruments - neither of
which were notably more reliable than the generators they backed
up. The objective being to be able to survive a failure. And
fail they did. The expected life of mags and vacuum pumps
ranges from 500 to 1000 hrs with frequent sporadic early
failures. Alternators OTOH are practically bullet proof. The
main thing that fails is the drive belt. Batteries also have
come a long way in the 60 years since generators and rudimentary
batteries compelled the development of vacuum driven instruments
and mag ignition.

I think solid state EVERYTHING and a bullet proof electrical
system is the rational way to go ... Jim S.

Brian Michalk wrote:

> I agree with electrical.  If you are not comfortable with
> solid state, RC Allen makes electric gyros for sale at
> aircraft spruce.Much easier to design a redundant electrical
> system than redundant vacuum.  Brian Michalk
> <http://www.michalk.com>
> Life is what you make of it ... never wish you had done
> something.
> Aviator, experimental aircraft builder, motorcyclist, SCUBA
> diver
> musician, home-brewer, entrepreneur and barely single
>
>
>      -----Original Message-----
>      From: reflector-admin@tvbf.org
>      [mailto:reflector-admin@tvbf.org]On Behalf Of Wayne
>      Sent: Friday, November 07, 2003 9:56 PM
>      To: reflector@tvbf.org
>      Subject: Re: REFLECTOR:V8 Vacuum system
>
>      Go solid  state. I built a bracket for a vacuum pump
>      on my PSRU  and even had a retractable vacuum
>      venturi.They sucked. I removed them both for an
>      electric gyro with a palm unit as a backup. Why put
>      unreliable dinosaur parts on a new plane?Wayne
>
>           ----- Original Message -----
>           From: velocityxlfg
>           To: reflector@tvbf.org
>           Sent: Monday, October 20, 2003 8:47 AM
>           Subject: REFLECTOR:V8 Vacuum system
>            Is there any one out there who put a
>           vacuum systemon an auto conversion? I have
>           a Chevy V8installed and would like some
>           ideas on how other peopleattacked the
>           Vacuum system. I thought of a
>           electricaldriven vacuum pump but do not
>           know how muchvacuum I need to pull. I
>           bought a engine driven aircraft pump. But
>           with it I need to find out what Rpm  it
>           needs to be run at? Where it mount it ?And
>           how I might install it.Or should I just
>           give up on the vacuum system all to
>           gertherand go all electrical. Thank you
>           Wise onesRon
>
--
Jim Sower
Crossville, TN; Chapter 5
Long-EZ N83RT, Velocity N4095T

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I think it's worth examining the whole issue and looking at why things
are the way they are ...
 &lt;... If you
are not comfortable with solid state ...>
 You might be
well advised to examine what that (the discomfort AND the technology) is
all about.
 &lt;... RC Allen
makes electric gyros ...>
 ... have all
the delicate, wearing, precessing moving parts of the vacuum units ...
 &lt;...&nbsp;
easier to design a redundant electrical system&nbsp; ...>
 Actually, the
alternators and batteries available these days are so reliable that if
either one is backed up, you have a basically bulletproof system.&nbsp;
Redundant batteries are an easy and inexpensive solution.&nbsp; in the
worst case scenario, an alternator failure becomes a "blip" since you have
an hour or an hour or two to get to a suitable landing field and then repairs
are as close as the nearest NAPA store.
&lt;... than
redundant vacuum ...>
 Let's remember
the reason we HAVE [notoriously expensive and unreliable] vacuum systems
in the first place.&nbsp; In the olden days (30s, 40s and 50s) generators
were so unreliable, what with high wear brushes, delicate stators and failure
prone armature windings, that they HAD to be backed up.&nbsp; We ended
up with magneto ignition and vacuum driven instruments - neither of which
were notably more reliable than the generators they backed up.&nbsp; The
objective being to be able to survive a failure.&nbsp; And fail they did.&nbsp;
The expected life of mags and vacuum pumps ranges from 500 to 1000 hrs
with frequent sporadic early failures.&nbsp; Alternators OTOH are practically
bullet proof.&nbsp; The main thing that fails is the drive belt.&nbsp;
Batteries also have come a long way in the 60 years since generators and
rudimentary batteries compelled the development of vacuum driven instruments
and mag ignition.
I think solid
state EVERYTHING and a bullet proof electrical system is the rational way
to go ... Jim S.
Brian Michalk wrote:
<blockquote TYPE=CITE><style></style>
I
agree with electrical.&nbsp; If you are not comfortable with solid state,
RC Allen makes electric gyros for sale at aircraft spruce.Much
easier to design a redundant electrical system than redundant vacuum.&nbsp;&nbsp;Brian
Michalk&nbsp; &lt;<a href="http://www.michalk.com/" target="_blank">http://www.michalk.com</a>>
 Life is what you make of it ... never wish you had done
something.
 Aviator, experimental aircraft builder, motorcyclist,
SCUBA diver
 musician, home-brewer, entrepreneur and barely single
 &nbsp;
<blockquote dir=ltr 
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
<div class="OutlookMessageHeader" dir="ltr">-----Original
Message-----
 From: reflector-admin@tvbf.org
[<A HREF="mailto:reflector-admin@tvbf.org">mailto:reflector-admin@tvbf.org</A>]On Behalf Of Wayne
 Sent: Friday, November 07,
2003 9:56 PM
 To: reflector@tvbf.org
 Subject: Re: REFLECTOR:V8
Vacuum system
 &nbsp;</div>
Go solid&nbsp; state. I built a bracket
for a vacuum pump on my PSRU&nbsp; and even had a retractable vacuum venturi.They
sucked. I removed them both for an&nbsp; electric gyro with a palm unit
as a backup. Why put unreliable dinosaur parts on a new plane?Wayne
<blockquote dir=ltr 
 style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<div style="FONT: 10pt arial">----- Original Message -----</div>

<div 
    style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><b>From:</b>
<a href="mailto:velocityxl@fastmail.fm" title="velocityxl@fastmail.fm">velocityxlfg</a></div>

<div style="FONT: 10pt arial"><b>To:</b> <a href="mailto:reflector@tvbf.org" title="reflector@tvbf.org">reflector@tvbf.org</a></div>

<div style="FONT: 10pt arial"><b>Sent:</b> Monday, October 20, 2003 8:47
AM</div>

<div style="FONT: 10pt arial">Subject: REFLECTOR:V8 Vacuum system</div>
&nbsp;Is there any one out there who put
a vacuum systemon an auto
conversion? I have a Chevy V8installed
and would like some ideas on how other peopleattacked
the Vacuum system. I thought of a electricaldriven
vacuum pump but do not know how muchvacuum
I need to pull. I bought a engine driven aircraft pump. But with it I need
to find out what Rpm&nbsp; it needs to be run at? Where it mount it ?And
how I might install it.Or
should I just give up on the vacuum system all to gertherand
go all electrical.&nbsp;Thank
you Wise onesRon</blockquote>
</blockquote>
</blockquote>

<p>--
<br>Jim Sower
<br>Crossville, TN; Chapter 5
<br>Long-EZ N83RT, Velocity N4095T
<br>&nbsp;
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