Why were there not many Pazmany PL4's built ?

Here's one I saw Fly back in 1982 at Red Deer Alberta

http://www.abpic.co.uk/photo/1019962/

On Sun, 24 Feb 2008 09:17:45 -0800 (PST), "(Keith Sowter)"
> wrote:

> Why were there not many Pazmany PL4's built ?
>
> Here's one I saw Fly back in 1982 at Red Deer Alberta
>
> http://www.abpic.co.uk/photo/1019962/

IIRC, they were more difficult to build than other homebuilts of that era. In
addition, single-seaters generally are generally not as popular.

Ron Wanttaja

On Sun, 24 Feb 2008 09:17:45 -0800 (PST), "(Keith Sowter)"
> wrote:

>Why were there not many Pazmany PL4's built ?
>
>Here's one I saw Fly back in 1982 at Red Deer Alberta
>
>http://www.abpic.co.uk/photo/1019962/


Keith

errata

A USAF Advisor to the Tiawan Air Force suggested they build a Pazmany
as a primary trainer for the Tiawan Air Force.

They built over 50 of them and assisted the Air Force Advisor in
building one for him on their production line using their tooling
which he shipped back to States.

Big John

"Big John" > wrote in message
...
> On Sun, 24 Feb 2008 09:17:45 -0800 (PST), "(Keith Sowter)"
> > wrote:
>
>>Why were there not many Pazmany PL4's built ?
>>
>>Here's one I saw Fly back in 1982 at Red Deer Alberta
>>
>>http://www.abpic.co.uk/photo/1019962/
>
>
> Keith
>
> errata
>
> A USAF Advisor to the Tiawan Air Force suggested they build a Pazmany
> as a primary trainer for the Tiawan Air Force.
>
> They built over 50 of them and assisted the Air Force Advisor in
> building one for him on their production line using their tooling
> which he shipped back to States.
>
> Big John
>
>
Were those PL2s? I have seen one PL2 in operation, and it would have been a
good plane for the job.

IIRC, before VanGrunsven revolutionized amateur metal airplane building, the
popular wisdom was that anyone who built a metal airplane really built 2--1
in wood and then 1 in metal. While not litterally true, the process of
building formers had to be remarkably tedious; so production tooling would
have been a really dramatic improvement and 50 airplanes were probably much
less than 10 times as much work as 1.

Peter

On Feb 24, 2:47*pm, Big John > wrote:
> ...A USAF Advisor to the Tiawan Air Force suggested they build
> a Pazmany as a primary trainer for the Tiawan Air Force.
>
> They built over 50 of them...

Note that those were actually PL1s, not PL4s. Actually, they were a
modification of the PL1, with a widened fuselage. They're generally
referred to as PL1B. A few of them have turned up in private hands.

Thanks, Bob K.

On Feb 24, 5:47*pm, Big John > wrote:
> On Sun, 24 Feb 2008 09:17:45 -0800 (PST), "(Keith Sowter)"
>
> > wrote:
> >Why were there not many Pazmany PL4's built ?
>
> >Here's one I saw Fly back in 1982 at Red Deer Alberta
>
> >http://www.abpic.co.uk/photo/1019962/
>
> Keith
>
> errata
>
> A USAF Advisor to the Tiawan Air Force suggested they build a Pazmany
> as a primary trainer for the Tiawan Air Force.
>
> They built over 50 of them and assisted the Air Force Advisor in
> building one for him on their production line using their tooling
> which he shipped back to States.
>
> Big John

Interesting that many countries are choosing to build and use
kitplanes for their primery trainers. I think I read elsewhere that
the Iraqi Air Force is using several different types of kitplanes,
AeroComp, Inc.s Comp Air 7SL being one of them, although not as a
trainer. http://www.af.mil/news/story.asp?id=123019902

Wil

Wil

On Sun, 24 Feb 2008 18:47:23 -0500, "Peter Dohm"
> wrote:

>"Big John" > wrote in message
...
>> On Sun, 24 Feb 2008 09:17:45 -0800 (PST), "(Keith Sowter)"
>> > wrote:
>>
>>>Why were there not many Pazmany PL4's built ?
>>>
>>>Here's one I saw Fly back in 1982 at Red Deer Alberta
>>>
>>>http://www.abpic.co.uk/photo/1019962/
>>
>>
>> Keith
>>
>> errata
>>
>> A USAF Advisor to the Tiawan Air Force suggested they build a Pazmany
>> as a primary trainer for the Tiawan Air Force.
>>
>> They built over 50 of them and assisted the Air Force Advisor in
>> building one for him on their production line using their tooling
>> which he shipped back to States.
>>
>> Big John
>>
>>
>Were those PL2s? I have seen one PL2 in operation, and it would have been a
>good plane for the job.
>
>IIRC, before VanGrunsven revolutionized amateur metal airplane building, the
>popular wisdom was that anyone who built a metal airplane really built 2--1
>in wood and then 1 in metal. While not litterally true, the process of
>building formers had to be remarkably tedious; so production tooling would
>have been a really dramatic improvement and 50 airplanes were probably much
>less than 10 times as much work as 1.
>
>Peter
>


**********************************

Peter

Knew the ones they built were two place (had to be as a primary
trainer :o) just didn't remember the model number given to them. Think
EAA had an article many years ago in Sport Avn about that bird he
built and brought back to US.

Google shows them as PL-1B's. Data also shows that some of them flew
10,000 hours as trainers so pretty tough birds.

No idea who owns that bird now. Seem to recall that the AF Pilot who
brought back died at a fairly early age (not in an aircraft accident)
as I remember.

Big John

"Big John" > wrote in message
...
> On Sun, 24 Feb 2008 18:47:23 -0500, "Peter Dohm"
> > wrote:
>
>>"Big John" > wrote in message
...
>>> On Sun, 24 Feb 2008 09:17:45 -0800 (PST), "(Keith Sowter)"
>>> > wrote:
>>>
>>>>Why were there not many Pazmany PL4's built ?
>>>>
>>>>Here's one I saw Fly back in 1982 at Red Deer Alberta
>>>>
>>>>http://www.abpic.co.uk/photo/1019962/
>>>
>>>
>>> Keith
>>>
>>> errata
>>>
>>> A USAF Advisor to the Tiawan Air Force suggested they build a Pazmany
>>> as a primary trainer for the Tiawan Air Force.
>>>
>>> They built over 50 of them and assisted the Air Force Advisor in
>>> building one for him on their production line using their tooling
>>> which he shipped back to States.
>>>
>>> Big John
>>>
>>>
>>Were those PL2s? I have seen one PL2 in operation, and it would have been
>>a
>>good plane for the job.
>>
>>IIRC, before VanGrunsven revolutionized amateur metal airplane building,
>>the
>>popular wisdom was that anyone who built a metal airplane really built
>>2--1
>>in wood and then 1 in metal. While not litterally true, the process of
>>building formers had to be remarkably tedious; so production tooling would
>>have been a really dramatic improvement and 50 airplanes were probably
>>much
>>less than 10 times as much work as 1.
>>
>>Peter
>>
>
>
> **********************************
>
> Peter
>
> Knew the ones they built were two place (had to be as a primary
> trainer :o) just didn't remember the model number given to them. Think
> EAA had an article many years ago in Sport Avn about that bird he
> built and brought back to US.
>
> Google shows them as PL-1B's. Data also shows that some of them flew
> 10,000 hours as trainers so pretty tough birds.
>
> No idea who owns that bird now. Seem to recall that the AF Pilot who
> brought back died at a fairly early age (not in an aircraft accident)
> as I remember.
>
> Big John

John,

Just after I posted, I saw Bob K's post and did a Google search as well--and
of course I found the same thing. I am still not sure what the differences
are between the PL1B and the PL2. I suppose that it is even possible that
the PL1B served as partial motivation for the PL2--especially as there have
been a few other O-320 powered PL1's built.

BTW, to the best of my personal recollection, I was unaware of the PL1 until
this evening.

Peter

On Feb 25, 12:25*am, William Hung > wrote:
> On Feb 24, 5:47*pm, Big John > wrote:
>
>
>
>
>
> > On Sun, 24 Feb 2008 09:17:45 -0800 (PST), "(Keith Sowter)"
>
> > > wrote:
> > >Why were there not many Pazmany PL4's built ?
>
> > >Here's one I saw Fly back in 1982 at Red Deer Alberta
>
> > >http://www.abpic.co.uk/photo/1019962/
>
> > Keith
>
> > errata
>
> > A USAF Advisor to the Tiawan Air Force suggested they build a Pazmany
> > as a primary trainer for the Tiawan Air Force.
>
> > They built over 50 of them and assisted the Air Force Advisor in
> > building one for him on their production line using their tooling
> > which he shipped back to States.
>
> > Big John
>
> Interesting that many countries are choosing to build and use
> kitplanes for their primery trainers. *I think I read elsewhere that
> the Iraqi Air Force is using several different types of kitplanes,
> AeroComp, Inc.s Comp Air 7SL being one of them, although not as a
> trainer. *http://www.af.mil/news/story.asp?id=123019902
>
> Wil
>
> Wil- Hide quoted text -
>
> - Show quoted text -

The Nigerian Airforce has RV6's.

"JohnO" > wrote . . .

> The Nigerian Airforce has RV6's.

France had some Emeraudes, but they were the certified European production
model.

Does that mean that RV6's, Emeraudes, and any other of the ilk are qualified
to park on the Warbird line? That'd be kinda neat! Those big iron drivers
always seem to get good parking and "crew members" with great looking
tushes. :))

Rich S.

"Rich S." > wrote in message
...
> "JohnO" > wrote . . .
>
>> The Nigerian Airforce has RV6's.
>
> France had some Emeraudes, but they were the certified European production
> model.
>
> Does that mean that RV6's, Emeraudes, and any other of the ilk are
> qualified to park on the Warbird line? That'd be kinda neat! Those big
> iron drivers always seem to get good parking and "crew members" with great
> looking tushes. :))
>
> Rich S.
>
Those alleged crew members are actually "Hangar Princesses" since those old
heavy iron warbirds are the real "Hangar Queens"

Peter
Striving for accuracy and tradition in nomenclature. ;-)

On Feb 25, 3:41*pm, "Peter Dohm" > wrote:
> "Rich S." > wrote in message
>
> ...> "JohnO" > wrote . . .
>
> >> The Nigerian Airforce has RV6's.
>
> > France had some Emeraudes, but they were the certified European production
> > model.
>
> > Does that mean that RV6's, Emeraudes, and any other of the ilk are
> > qualified to park on the Warbird line? That'd be kinda neat! Those big
> > iron drivers always seem to get good parking and "crew members" with great
> > looking tushes. *:))
>
> > Rich S.
>
> Those alleged crew members are actually "Hangar Princesses" since those old
> heavy iron warbirds are the real "Hangar Queens"
>
> Peter
> Striving for accuracy and tradition in nomenclature. *;-)

We must not forget that the Peruvian Air Force bought a fleet of CGS
Hawks, however I've only heard what may be an urban legend about one
being armed. I think that it was a test of the super strafer model
during the great Ohio paint ball war.

If you read Pazmany's book " Light Airplane Construction for amateur
builders" you will see that the PL series of planes looks pretty work
intensive. More like a factory built than your basic homebuilt. Looks
like 16 ribs on each wing and 7 bulkheads in the tailcone. It is well
put together and no doubt a strong design ,but complicated to build.

Frank M.Hitlaw at my secret World Hq

On Feb 24, 9:17 am, "(Keith Sowter)"
> wrote:
> Why were there not many Pazmany PL4's built ?
>
> Here's one I saw Fly back in 1982 at Red Deer Alberta
>
> http://www.abpic.co.uk/photo/1019962/

Here's what I said about it on my website on VW powered homebuilts:

"Conventional gear single seat low wing all metal T-tail Aerobatic.
Laszlo got tired of taking heat for how long it took amateurs to build
PL-2's, and the energy crisis was upon us, so he designed a VW-powered
plane that only took 3000 hours instead of 6000 hours to build. The
belt reduction 1600cc engine didn't make the power he thought it
would, and very few, if any, other than the prototype, were actually
built with the engine it was designed for. A rugged, well engineered
airplane, with exceptional plans and builder's manual. I'll say that
again, you will not find a finer set of plans, and the assembly manual
is a complete education in building a metal airplane. I'll bet with a
bigger engine, and one of the Smith Engineering belt reductions that
GPASC sells it would go pretty good."

I've since heard from Veeduber (who knew Pazmany, and flew out of the
same airport as the prototype) that you could smell the first ship
before you could see it, as it burned, errr flew off the first 40
hours with the belts constantly slipping.

They ARE hell for stout, plus/minus 9G I think.

On Feb 25, 10:58 pm, flybynightkarmarepair > wrote:

> I've since heard from Veeduber (who knew Pazmany, and flew out of the
> same airport as the prototype) that you could smell the first ship
> before you could see it, as it burned, errr flew off the first 40
> hours with the belts constantly slipping.
>------------------------------------------------------------------

Well... mebbe it wasn't quite that bad... :-) But with multiple vee
belts it's impossible to keep ALL of them at the same tension. The
loosest of them would slip and there was a definite pong of hot rubber
after every flight.

Several of us who had experience flying behind VW's (Paz wasn't a
pilot back then) tried to explain the realities of VW engines to Paz
but he made it pretty clear that our experience-based opinions were
not welcome. (Come to think of it, a kid named Burt Something did
exactly the same :-)

In the final analysis the PL-4 -- at nearly 700 pounds -- is a heavy,
complex, expensive airframe that needs more power than a stock 1600 VW
engine can provide. With the same engine, a Teenie Two can fly rings
around it and is a lot easier to land, while a VP-1 is more fun than
either. But of course, those aren't 'real' airplanes... :-)

-R.S.Hoover

wrote:
> On Feb 25, 10:58 pm, flybynightkarmarepair > wrote:
>
>
>>I've since heard from Veeduber (who knew Pazmany, and flew out of the
>>same airport as the prototype) that you could smell the first ship
>>before you could see it, as it burned, errr flew off the first 40
>>hours with the belts constantly slipping.
>>------------------------------------------------------------------
>
>
> Well... mebbe it wasn't quite that bad... :-) But with multiple vee
> belts it's impossible to keep ALL of them at the same tension. The
> loosest of them would slip and there was a definite pong of hot rubber
> after every flight.

Eh? I can't visualize it. Either all, or none, slip.

Beryl wrote:
> wrote:
>
>> On Feb 25, 10:58 pm, flybynightkarmarepair > wrote:
>>
>>
>>> I've since heard from Veeduber (who knew Pazmany, and flew out of the
>>> same airport as the prototype) that you could smell the first ship
>>> before you could see it, as it burned, errr flew off the first 40
>>> hours with the belts constantly slipping.
>>> ------------------------------------------------------------------
>>
>>
>>
>> Well... mebbe it wasn't quite that bad... :-) But with multiple vee
>> belts it's impossible to keep ALL of them at the same tension. The
>> loosest of them would slip and there was a definite pong of hot rubber
>> after every flight.
>
>
> Eh? I can't visualize it. Either all, or none, slip.

Nope. That's not how it works, Beryl.

Oh, maybe if all the belts really were teh exact same size.
Or if the pulleys were really exactly parallel.

In the real world neither of thoese little details ever work out - quite
that exactly.

The biggest one slips.

How can you tell which is the biggest one?
Easy.
It's the one that slips!

As tehy say, YMMV...



Richard

cavelamb himself wrote:

> Beryl wrote:
>
>> wrote:
>>
>>> On Feb 25, 10:58 pm, flybynightkarmarepair > wrote:
>>>
>>>
>>>> I've since heard from Veeduber (who knew Pazmany, and flew out of the
>>>> same airport as the prototype) that you could smell the first ship
>>>> before you could see it, as it burned, errr flew off the first 40
>>>> hours with the belts constantly slipping.
>>>> ------------------------------------------------------------------
>>>
>>>
>>>
>>>
>>> Well... mebbe it wasn't quite that bad... :-) But with multiple vee
>>> belts it's impossible to keep ALL of them at the same tension. The
>>> loosest of them would slip and there was a definite pong of hot rubber
>>> after every flight.
>>
>>
>>
>> Eh? I can't visualize it. Either all, or none, slip.
>
>
> Nope. That's not how it works, Beryl.
>
> Oh, maybe if all the belts really were teh exact same size.
> Or if the pulleys were really exactly parallel.
>
> In the real world neither of thoese little details ever work out - quite
> that exactly.
>
> The biggest one slips.
>
> How can you tell which is the biggest one?
> Easy.
> It's the one that slips!
>
> As tehy say, YMMV...
>
>
>
> Richard

My mileage varies. I tink teh biggest belt is just along for teh ride.
And in teh real world, even teh tightiest belt slips if you're talking
about microscopically wobbling pulleys.

On Feb 26, 8:23*am, cavelamb himself > wrote:
> Beryl wrote:
> > wrote:
>
> >> On Feb 25, 10:58 pm, flybynightkarmarepair > wrote:
>
> >>> I've since heard from Veeduber (who knew Pazmany, and flew out of the
> >>> same airport as the prototype) that you could smell the first ship
> >>> before you could see it, as it burned, errr flew off the first 40
> >>> hours with the belts constantly slipping.
> >>> ------------------------------------------------------------------
>
> >> Well... mebbe it wasn't quite that bad... :-) *But with multiple vee
> >> belts it's impossible to keep ALL of them at the same tension. *The
> >> loosest of them would slip and there was a definite pong of hot rubber
> >> after every flight.
>
> > Eh? I can't visualize it. Either all, or none, slip.
>
> Nope. *That's not how it works, Beryl.
>
> Oh, maybe if all the belts really were teh exact same size.
> Or if the pulleys were really exactly parallel.
>
> In the real world neither of thoese little details ever work out - quite
> that exactly.
>
> The biggest one slips.
>
> How can you tell which is the biggest one?
> Easy.
> It's the one that slips!
>
> As tehy say, YMMV...
>
> Richard- Hide quoted text -
>
> - Show quoted text -

Caveman, you cannot have one belt slipping and not the others. Think
about it - the pulleys on each shaft are all the same size and
rotating at the same speed. You can only have slip if one pulley is
rotating at a different speed to the other. If one slips they *must*
all slip.

"Beryl" > wrote in message
...
> wrote:
>> On Feb 25, 10:58 pm, flybynightkarmarepair > wrote:
>>
>>
>>>I've since heard from Veeduber (who knew Pazmany, and flew out of the
>>>same airport as the prototype) that you could smell the first ship
>>>before you could see it, as it burned, errr flew off the first 40
>>>hours with the belts constantly slipping.
>>>------------------------------------------------------------------
>>
>>
>> Well... mebbe it wasn't quite that bad... :-) But with multiple vee
>> belts it's impossible to keep ALL of them at the same tension. The
>> loosest of them would slip and there was a definite pong of hot rubber
>> after every flight.
>
> Eh? I can't visualize it. Either all, or none, slip.

I must admit that I am having a little trouble visualizing this one as
well--unless that loosest belt was either the farthest from the engine or
the farthest from the prop. In those cases, I have no trouble at all.

Peter

On Tue, 26 Feb 2008 03:00:47 -0800 (PST), JohnO >
wrote:

>On Feb 26, 8:23=A0am, cavelamb himself > wrote:
>> Beryl wrote:
>> > wrote:
>>
>> >> On Feb 25, 10:58 pm, flybynightkarmarepair > wrote:
>>
>> >>> I've since heard from Veeduber (who knew Pazmany, and flew out of the
>> >>> same airport as the prototype) that you could smell the first ship
>> >>> before you could see it, as it burned, errr flew off the first 40
>> >>> hours with the belts constantly slipping.
>> >>> ------------------------------------------------------------------
>>
>> >> Well... mebbe it wasn't quite that bad... :-) =A0But with multiple vee
>> >> belts it's impossible to keep ALL of them at the same tension. =A0The
>> >> loosest of them would slip and there was a definite pong of hot rubber
>> >> after every flight.
>>
>> > Eh? I can't visualize it. Either all, or none, slip.
>>
>> Nope. =A0That's not how it works, Beryl.
>>
>> Oh, maybe if all the belts really were teh exact same size.
>> Or if the pulleys were really exactly parallel.
>>
>> In the real world neither of thoese little details ever work out - quite
>> that exactly.
>>
>> The biggest one slips.
>>
>> How can you tell which is the biggest one?
>> Easy.
>> It's the one that slips!
>>
>> As tehy say, YMMV...
>>
>> Richard- Hide quoted text -
>>
>> - Show quoted text -
>
>Caveman, you cannot have one belt slipping and not the others. Think
>about it - the pulleys on each shaft are all the same size and
>rotating at the same speed. You can only have slip if one pulley is
>rotating at a different speed to the other. If one slips they *must*
>all slip.

The longest one slips on both pulleys.

On Feb 26, 2:46*pm, (Drew Dalgleish)
wrote:
> On Tue, 26 Feb 2008 03:00:47 -0800 (PST), JohnO >
> wrote:
>
>
>
>
>
> >On Feb 26, 8:23=A0am, cavelamb himself > wrote:
> >> Beryl wrote:
> >> > wrote:
>
> >> >> On Feb 25, 10:58 pm, flybynightkarmarepair > wrote:
>
> >> >>> I've since heard from Veeduber (who knew Pazmany, and flew out of the
> >> >>> same airport as the prototype) that you could smell the first ship
> >> >>> before you could see it, as it burned, errr flew off the first 40
> >> >>> hours with the belts constantly slipping.
> >> >>> ------------------------------------------------------------------
>
> >> >> Well... mebbe it wasn't quite that bad... :-) =A0But with multiple vee
> >> >> belts it's impossible to keep ALL of them at the same tension. =A0The
> >> >> loosest of them would slip and there was a definite pong of hot rubber
> >> >> after every flight.
>
> >> > Eh? I can't visualize it. Either all, or none, slip.
>
> >> Nope. =A0That's not how it works, Beryl.
>
> >> Oh, maybe if all the belts really were teh exact same size.
> >> Or if the pulleys were really exactly parallel.
>
> >> In the real world neither of thoese little details ever work out - quite
> >> that exactly.
>
> >> The biggest one slips.
>
> >> How can you tell which is the biggest one?
> >> Easy.
> >> It's the one that slips!
>
> >> As tehy say, YMMV...
>
> >> Richard- Hide quoted text -
>
> >> - Show quoted text -
>
> >Caveman, you cannot have one belt slipping and not the others. Think
> >about it - the pulleys on each shaft are all the same size and
> >rotating at the same speed. You can only have slip if one pulley is
> >rotating at a different speed to the other. If one slips they *must*
> >all slip.
>
> The longest one slips on both pulleys.- Hide quoted text -
>
> - Show quoted text -

Are these belts zero stretch? If they are then I'd agree with you. The
only zero stretch belts I am familiar with are kevlar reinforced
toothed belts running on cogs.

As long as the belts in the original question are stretched so that
the longest one is now the same length as the shortest one there can
be no slip.

Peter,

It really doesn't matter WHERE in the lineup the longest belt is. You can
have two, or "very many", and absolutely none of them will be the exact same
length. One WILL be longer than all the others, and (by very keen
observation it will be also found) one of them will be shorter than all the
others. Always, one will carry more torque, horsepower, heat, friction, wear
(or your malady of choice) than others and share the rest of the
difficulties among its companions, and will lead to premature failure of one
belt or another.

Those difficulties, along with uneven stretch pattern among the individual
belts - thus making it hard to maintain proper tension on each and every
belt in the setup, is what gave rise to the new style of belts and pulleys.

Even pulleys that are quite carefully manufactured will still have the
grooves nearly exactly same angle and depth and diameter- but never exactly.
It is actually kind of like shooting fish in a barrel with a shotgun. You
have just got to wait and see what comes to view after all the smoke clears.

The plane and installation in question did not take advantage of the
"poly-V" single belt with multiple grooves - much like the serpentine
alternator belt on your 1980 F-150. And the "cog" type belt, as in timing
belts and synchronized drives was not an option then, either. Multiple
vee-belts were a compromise solution, and the difficulties associated with
that solution were what came along with the perceived benefits, like rpm,
power, weight, cost.

Flash




"Peter Dohm" > wrote in message
. ..
>
> "Beryl" > wrote in message
> ...
>> wrote:
>>> On Feb 25, 10:58 pm, flybynightkarmarepair > wrote:
>>>
>>>
>>>>I've since heard from Veeduber (who knew Pazmany, and flew out of the
>>>>same airport as the prototype) that you could smell the first ship
>>>>before you could see it, as it burned, errr flew off the first 40
>>>>hours with the belts constantly slipping.
>>>>------------------------------------------------------------------
>>>
>>>
>>> Well... mebbe it wasn't quite that bad... :-) But with multiple vee
>>> belts it's impossible to keep ALL of them at the same tension. The
>>> loosest of them would slip and there was a definite pong of hot rubber
>>> after every flight.
>>
>> Eh? I can't visualize it. Either all, or none, slip.
>
> I must admit that I am having a little trouble visualizing this one as
> well--unless that loosest belt was either the farthest from the engine or
> the farthest from the prop. In those cases, I have no trouble at all.
>
> Peter
>
>
>

"Drew Dalgleish" > wrote
>
> The longest one slips on both pulleys.

Think about it for a moment...

If one belt is a little longer, it would not be able to carry as much power,
because it is not as tight as the others.

The others tight belts will carry nearly all of the power, up until the
point where they can not carry all of the power. Then the tight ones will
start to slip.

If the long belt is not able to carry power, but the short tight ones can
carry all of the power being produced, then there will be no slippage.

It is counter intuitive, but that is the situation. If there are 4 belts,
and three can carry all of the HP, and the 4th one is loose, it will not
slip. It will not be carrying any power, though.

If all 4 belts have to be pulling equal load to be able to carry all the HP
being produced, and one belt is loose, then the tight 3 will slip, because
the 4th loose belt can not carry its share, and is slipping.

In my experience of multi V-belt farm type equipment, if you start with 4
new identical belts, and they are a well matched set of identical lengths,
they all will pull evenly. If one is loose, they will slip like I said
above, and will often times stretch to be more closely matched and start
pulling more evenly, if there is enough tension to pull them back tight, and
you do not completely glaze the belts from the initial slipping.

I bet the multiple V-belt reduction unit is running at a very high
percentage of maximum HP recommended by the belt manufacturer. It would be
more likely to smell like burned belts than most farm type applications,
where the loads are kept more conservative by just adding more belts.
--
Jim in NC

On Feb 26, 12:02 pm, "flash" > wrote:
.......
What he said. Plus the fact #4 ovaled out quick like a bunny as the
asymmetric load was increased (ie, trying to offset the belt
slippage) ... which also wore out the lower pulley.

The craziest part was that Walt Mooney had similar problems with the
Crosley (sp?) powered Mite... and he was standing right there :-)

-R.S.Hoover

"Morgans" > wrote in message
...
>
> "Drew Dalgleish" > wrote
>>
>> The longest one slips on both pulleys.
>
> Think about it for a moment...
>
> If one belt is a little longer, it would not be able to carry as much
> power, because it is not as tight as the others.
>
> The others tight belts will carry nearly all of the power, up until the
> point where they can not carry all of the power. Then the tight ones will
> start to slip.
>
> If the long belt is not able to carry power, but the short tight ones can
> carry all of the power being produced, then there will be no slippage.
>
> It is counter intuitive, but that is the situation. If there are 4 belts,
> and three can carry all of the HP, and the 4th one is loose, it will not
> slip. It will not be carrying any power, though.
>
> If all 4 belts have to be pulling equal load to be able to carry all the
> HP being produced, and one belt is loose, then the tight 3 will slip,
> because the 4th loose belt can not carry its share, and is slipping.
>
> In my experience of multi V-belt farm type equipment, if you start with 4
> new identical belts, and they are a well matched set of identical lengths,
> they all will pull evenly. If one is loose, they will slip like I said
> above, and will often times stretch to be more closely matched and start
> pulling more evenly, if there is enough tension to pull them back tight,
> and you do not completely glaze the belts from the initial slipping.
>
> I bet the multiple V-belt reduction unit is running at a very high
> percentage of maximum HP recommended by the belt manufacturer. It would
> be more likely to smell like burned belts than most farm type
> applications, where the loads are kept more conservative by just adding
> more belts.
> --
> Jim in NC
>
Thanks Jim,

That is all in keeping with what I had always understood, and also makes a
great point about conservative versus optomistic designs.

Peter