The Home-made Home-builders Engine

[Veeduber[_2_]]

To All:

For those of us who own a lathe and milling machine, somewhere in our
past there is probably a tiny steam engine. Indeed, there's probably
more than than one. A company in England provides the basic castings
as a kit. As the machinist, you are expected to provide all else,
from the machine to do the work to the KNOWLEDGE needed to operate the
machine.

Producing such an engine, from the basic one-cylinder model to larger
engines of remarkable complexity, serves as silent testimony as to our
abilities.

It strikes me as little more than a step along the way to produce a
FULL SIZE engine such as the Pobjoy. The crankshaft calls for a
professional piece of goods, probably obtainable from a Chinese
manufacturer, but the cylinders, being identical, call for much less
in the way of skills and tooling. With cast-iron cylinder barrels and
cast aluminum heads, the bulk of the engine can be produced on the
tooling found in the shops of literally thousands of amateur
machinists found in every country around the world.

While the copyright to the engine is presently held by the same
company that produces the Rotax, there are enough example of the
Pobjoy in aviation museums that it would be a relatively minor chore
to produce a set of drawings. Indeed, knowing the engine's bore &
stroke even a good PHOTOGRAPH gives a wealth of data leading to a
usable drawing. So long as those drawings contained significant
differences from the original there should be no question as to
violation of those rights. Such differences could be calling out
parts and bearings NOT used in the original Pobjoy.

With suitable drawings in hand we could produce the required molds
needed to produce the required castings. The drawings will also tell
us what gears and bearings are required, allowing us to order them
from suppliers who deal in such components. The drawings will also
show what type of valve guides are needed and even the valves, springs
and rocker-arms. With a bore of 75mm and a stroke of 87, we can
determine what EXISTING pistons my be used as well as the size of the
carburetor that is required.

The 'Experiment- Amateur-built' licensing category exists to promote
aeronautical education in America. Learning how radial engines work
and even building one yourself is no more difficult, in my opinion,
than building your own airframe.

-Robert S. Hoover

[Bob Murray]

"Veeduber" > wrote in message
...
> To All:
>
> For those of us who own a lathe and milling machine, somewhere in our
> past there is probably a tiny steam engine. Indeed, there's probably
> more than than one. A company in England provides the basic castings
> as a kit. As the machinist, you are expected to provide all else,
> from the machine to do the work to the KNOWLEDGE needed to operate the
> machine.
>
> Producing such an engine, from the basic one-cylinder model to larger
> engines of remarkable complexity, serves as silent testimony as to our
> abilities.
>
> It strikes me as little more than a step along the way to produce a
> FULL SIZE engine such as the Pobjoy. The crankshaft calls for a
> professional piece of goods, probably obtainable from a Chinese
> manufacturer, but the cylinders, being identical, call for much less
> in the way of skills and tooling. With cast-iron cylinder barrels and
> cast aluminum heads, the bulk of the engine can be produced on the
> tooling found in the shops of literally thousands of amateur
> machinists found in every country around the world.
>
> While the copyright to the engine is presently held by the same
> company that produces the Rotax, there are enough example of the
> Pobjoy in aviation museums that it would be a relatively minor chore
> to produce a set of drawings. Indeed, knowing the engine's bore &
> stroke even a good PHOTOGRAPH gives a wealth of data leading to a
> usable drawing. So long as those drawings contained significant
> differences from the original there should be no question as to
> violation of those rights. Such differences could be calling out
> parts and bearings NOT used in the original Pobjoy.
>
> With suitable drawings in hand we could produce the required molds
> needed to produce the required castings. The drawings will also tell
> us what gears and bearings are required, allowing us to order them
> from suppliers who deal in such components. The drawings will also
> show what type of valve guides are needed and even the valves, springs
> and rocker-arms. With a bore of 75mm and a stroke of 87, we can
> determine what EXISTING pistons my be used as well as the size of the
> carburetor that is required.
>
> The 'Experiment- Amateur-built' licensing category exists to promote
> aeronautical education in America. Learning how radial engines work
> and even building one yourself is no more difficult, in my opinion,
> than building your own airframe.
>
> -Robert S. Hoover
>

There is also the Lawrance 5-cyl. radial, about 35 HP from 75 cubic inches,
and a crankcase just under 9" in diameter.

As far as crankshafts, most radials used built-up cranks which can be
machined fairly easily. In the size of engine under discussion, the parts
that need to be ground can be finished on any commercial tool & cutter
grinder, and then assembled.

BTW, 75 cubic inches works out to 250cc per cylinder - how many 250 singles,
500 twins, and 1000-1200 fours are out there that could donate pistons,
pins, & rings; valves, springs & keepers, etc.?

Another Bob

[Veeduber[_2_]]

On May 29, 3:12*pm, Charles Vincent > wrote:

> They do have an OHV version I believe. * At the RPM's these engines run
> at i.e. direct drive prop, I am not sure the L head is that much of a
> compromise.
> ----------------------------------------------------------------------------------------

All of the Pobjoy's were geared, OHV engines. They produced 80hp @
3300 rpm (prop speed of 1400rpm). Weight was 130 lbs.

-R.S.Hoover

[Charles Vincent]

Veeduber wrote:
> On May 29, 3:12 pm, Charles Vincent > wrote:
>
>> They do have an OHV version I believe. At the RPM's these engines run
>> at i.e. direct drive prop, I am not sure the L head is that much of a
>> compromise.
>> ----------------------------------------------------------------------------------------
>
> All of the Pobjoy's were geared, OHV engines. They produced 80hp @
> 3300 rpm (prop speed of 1400rpm). Weight was 130 lbs.
>
> -R.S.Hoover
>

I was referring to the HCI Radials which are ungeared. I have seen the
Pobjoy. I have collected everything I can get my hands on with regard
to small radial engines. I have even managed to find factory blueprints
for parts of the Kinner and a Leblonde. No prints sadly for the Pobjoy,
just some contemporaneous technical reviews that do have three views of
the engine. There was a Pobjoy on display in a museum outside San Jose,
but that is a trek from your 20.

Charles

[bildan]

On May 29, 12:50*pm, "Bob Murray" > wrote:
> "Veeduber" > wrote in message
>
> ...
>
>
>
> > To All:
>
> > For those of us who own a lathe and milling machine, somewhere in our
> > past there is probably a tiny steam engine. *Indeed, there's probably
> > more than than one. *A company in England provides the basic castings
> > as a kit. *As the machinist, you are expected to provide all else,
> > from the machine to do the work to the KNOWLEDGE needed to operate the
> > machine.
>
> > Producing such an engine, from the basic one-cylinder model to larger
> > engines of remarkable complexity, serves as silent testimony as to our
> > abilities.
>
> > It strikes me as little more than a step along the way to produce a
> > FULL SIZE engine such as the Pobjoy. *The crankshaft calls for a
> > professional piece of goods, probably obtainable from a Chinese
> > manufacturer, but the cylinders, being identical, call for much less
> > in the way of skills and tooling. *With cast-iron cylinder barrels and
> > cast aluminum heads, the bulk of the engine can be produced on the
> > tooling found in the shops of literally thousands of amateur
> > machinists found in every country around the world.
>
> > While the copyright to the engine is presently held by the same
> > company that produces the Rotax, there are enough example of the
> > Pobjoy in aviation museums that it would be a relatively minor chore
> > to produce a set of drawings. Indeed, knowing the engine's bore &
> > stroke even a good PHOTOGRAPH gives a wealth of data leading to a
> > usable drawing. *So long as those drawings contained significant
> > differences from the original there should be no question as to
> > violation of those rights. *Such differences could be calling out
> > parts and bearings NOT used in the original Pobjoy.
>
> > With suitable drawings in hand we could produce the required molds
> > needed to produce the required castings. *The drawings will also tell
> > us what gears and bearings are required, allowing us to order them
> > from suppliers who deal in such components. *The drawings will also
> > show what type of valve guides are needed and even the valves, springs
> > and rocker-arms. *With a bore of 75mm and a stroke of 87, we can
> > determine what EXISTING pistons my be used as well as the size of the
> > carburetor that is required.
>
> > The 'Experiment- Amateur-built' licensing category exists to promote
> > aeronautical education in America. *Learning how radial engines work
> > and even building one yourself is no more difficult, in my opinion,
> > than building your own airframe.
>
> > -Robert S. Hoover
> >
>
> There is also the Lawrance 5-cyl. radial, about 35 HP from 75 cubic inches,
> and a crankcase just under 9" in diameter.
>
> As far as crankshafts, most radials used built-up cranks which can be
> machined fairly easily. *In the size of engine under discussion, the parts
> that need to be ground can be finished on any commercial tool & cutter
> grinder, and then assembled.
>
> BTW, 75 cubic inches works out to 250cc per cylinder - how many 250 singles,
> 500 twins, and 1000-1200 fours are out there that could donate pistons,
> pins, & rings; valves, springs & keepers, etc.?
>
> Another Bob

Seem to me that the most modern motorcycle cylinders would be the
best. Metallurgy is still advancing rapidly and there are a lot of
innovations in recent bikes. Some even use "diamond-like coatings" on
high wear parts like cams and followers.

Recall that the Merlin and Allison V-12's of WWII used dual overhead
cams and 4 valves per cylinder which is the norm for motorcycles
today.

I worked up a CAD drawing of a radial using 5 banks of 4-cylinder
500cc motorcycle cylinder blocks. (7 banks didn't leave enough room
for intake and exhaust plumbing between the blocks.) The result is an
amazingly small 20 cylinder liquid cooled radial engine.

20 cylinders is enough that you could stop worrying about 2-plugs per
cylinder. If you fouled a couple, you probably wouldn't notice.

Looking through race parts catalogs turned up automatic transmission
planetary gear sets that are rated for 1500hp but are only 6" in
diameter and weigh about 15 pounds. The gear ratios are just right
for a PSRU. If they stand up to the hammering from a drag racer,
handling a couple of hundred HP should be a breeze.

To build this engine would require making a case, crank and rods with
the planetary in a nose case with thrust bearings. (Of course a lot
of other fiddly bits would need to be made as well.) However, the
heads, cylinders and pistons are the hard part and they are available
cheap.

[Veeduber[_2_]]

On May 30, 9:21*am, bildan > wrote:

> To build this engine would require making a case, crank and rods with
> the planetary in a nose case with thrust bearings. *(Of course a lot
> of other fiddly bits would need to be made as well.) *However, the
> heads, cylinders and pistons are the hard part and they are available
> cheap.
--------------------------------------------------------------------------------------------------------

I disagree with regard to the heads and cylinders. But you are
correct when it comes to the gear reduction unit.

As several others have pointed out, publicly and in private messages,
there has been significant advances in metallurgy since the Pobjoy
first ran in 1926.

The Pobjoy had its share of problems, from its inception until its
production was finally dropped in 1946. But those problems would
probably not apply if the engine were produced today. For example,
the use of a planetary gear reduction system would eliminate the wear
problems encountered with the original herringbone gear, while a
modern, fully sealed valve train would improve the engine's mean time
before failure.

As for the question of using existing cylinders and heads, an aircraft
engine uses a different design philosophy than is used when producing
any other type of engine, although a stationary industrial engine
comes very close.

Ideally, the heads should follow standard aircraft engine practice in
the use of forgings rather than castings, although if the engine were
kitted, even partially so -- perhaps a pre-assembled lower end plus a
kit of parts for the cylinders and heads -- the price may be low
enough to satisfy the home-builder's budget limitations. For example,
if the heads were already machined, it does not take a great deal of
skill to swage the valve seats into place nor to stone them.
Volkswagen parts could be used for almost the entire valve train.

As a point of interest, while the basic idea is to produce an engine
sufficiently low in cost as to fulfill the needs of home-builders
around the world, should we be able to tap into a manufacturer at this
level, it is most likely they might be convinced to use their
facilities to produce the Fat-fin head needed to make the Volkswagen
engine more suitable than the existing engines by producing heads
having an honest sixty-five horsepower's-worth of fin area. Indeed,
this could be a method of subsidizing the cost of a 'replica' radial
-- OR OTHER ENGINE -- in that home-builders in those parts of the
world where Volkswagen components are still in good supply would
probably buy enough Fat-fin heads that their sale would provide the
start-up funds needed to get a more appropriate engine into
production.

Toward this end, while I mentioned the Pobjoy because of its excellent
ratio of power-to-weight, I also mentioned that an in-line engine such
as the de Havilland would be the least expensive.

This is another case where modern-day metallurgy may prove beneficial,
in that Lost Foam Casting might be used to produce the head and lower
end, using aftermarket air-cooled cylinders. The key to success in
this case would be the existence of a suitable crankshaft. That is,
one in which the throws are spaced sufficiently far apart to allow the
use of finned barrels.

-R.S.Hoover

[[email protected][_2_]]

On May 31, 12:35*am, Veeduber > wrote:

> , I also mentioned that an in-line engine such
> as the de Havilland would be the least expensive.
>
The key to success in
> this case would be the existence of a suitable crankshaft. *That is,
> one in which the throws are spaced sufficiently far apart to allow the
> use of finned barrels.

If I'm looking at this properly a standard VW water-cooled inline
crank (or most any similar 5 main bearing inline 4 crank) can be used
in a 90 deg. "V" 4. This would give plenty of room for fins. I think
all of the water-cooled VW cranks have 86mm or longer strokes and the
matching stock rods are between 7mm and 30mm longer than air-cooled
units, which should give good low speed torque. If it were a push rod
motor parts count would not be much greater than an inline?

A stub attached to the flywheel end of the crank and ground with the
mains to match a stock Continental front bearing, IMHO, would take
care of prop loads.
======================
Leon McAtee

[bildan]

On May 31, 12:35*am, Veeduber > wrote:
> On May 30, 9:21*am, bildan > wrote:
>
> > To build this engine would require making a case, crank and rods with
> > the planetary in a nose case with thrust bearings. *(Of course a lot
> > of other fiddly bits would need to be made as well.) *However, the
> > heads, cylinders and pistons are the hard part and they are available
> > cheap.
>
> --------------------------------------------------------------------------------------------------------
>
> I disagree with regard to the heads and cylinders. *But you are
> correct when it comes to the gear reduction unit.
>
> As several others have pointed out, publicly and in private messages,
> there has been significant advances in metallurgy since the Pobjoy
> first ran in 1926.
>
> The Pobjoy had its share of problems, from its inception until its
> production was finally dropped in 1946. *But those problems would
> probably not apply if the engine were produced today. *For example,
> the use of a planetary gear reduction system would eliminate the wear
> problems encountered with the original herringbone gear, while a
> modern, fully sealed valve train would improve the engine's mean time
> before failure.
>
> As for the question of using existing cylinders and heads, an aircraft
> engine uses a different design philosophy than is used when producing
> any other type of engine, although a stationary industrial engine
> comes very close.
>
> Ideally, the heads should follow standard aircraft engine practice in
> the use of forgings rather than castings, although if the engine were
> kitted, even partially so -- perhaps a pre-assembled lower end plus a
> kit of parts for the cylinders and heads -- *the price may be low
> enough to satisfy the home-builder's budget limitations. *For example,
> if the heads were already machined, it does not take a great deal of
> skill to swage the valve seats into place nor to stone them.
> Volkswagen parts could be used for almost the entire valve train.
>
> As a point of interest, while the basic idea is to produce an engine
> sufficiently low in cost as to fulfill the needs of home-builders
> around the world, should we be able to tap into a manufacturer at this
> level, it is most likely they might be convinced to use their
> facilities to produce *the Fat-fin head needed to make the Volkswagen
> engine more suitable than the existing engines by producing heads
> having an honest sixty-five horsepower's-worth of fin area. *Indeed,
> this could be a method of subsidizing the cost of a 'replica' radial
> -- OR OTHER ENGINE -- *in that home-builders in those parts of the
> world where Volkswagen components are still in good supply would
> probably buy enough Fat-fin heads that their sale would provide the
> start-up funds needed to get a more appropriate engine into
> production.
>
> Toward this end, while I mentioned the Pobjoy because of its excellent
> ratio of power-to-weight, I also mentioned that an in-line engine such
> as the de Havilland would be the least expensive.
>
> This is another case where modern-day metallurgy may prove beneficial,
> in that Lost Foam Casting might be used to produce the head and lower
> end, using aftermarket air-cooled cylinders. *The key to success in
> this case would be the existence of a suitable crankshaft. *That is,
> one in which the throws are spaced sufficiently far apart to allow the
> use of finned barrels.
>
> -R.S.Hoover

With respect, motorcycle heads are CNC machined from high strength
forged alloy billet. To my knowledge, no such head has ever failed
even under severe racing conditions.

The only 'top end' failures I'm aware of resulted from revving way
over red line RPM which caused valve failure. I know of a few which
suffered bent rods when the owner tried to start a hydraulically
locked engine after fuel had drained into a cylinder.

I would SWAG that top end motorcycle heads and cylinder blocks are
over designed for aircraft use by around 5X. The motorcycle news
group I belongs to recently asked if anyone had EVER overhauled their
engine due to simple wear. No one reported they had even though some
reported over 300,000 miles on their bikes. One reported tearing down
a high-mileage engine after the bike was wrecked just to find out what
the tolerances were - and to possibly re-use the parts. He reported
no measurable wear.

These are enormously strong engines and I think homebuilders should
take a serious look at them.

[Anthony W]

wrote:

> If I'm looking at this properly a standard VW water-cooled inline
> crank (or most any similar 5 main bearing inline 4 crank) can be used
> in a 90 deg. "V" 4. This would give plenty of room for fins. I think
> all of the water-cooled VW cranks have 86mm or longer strokes and the
> matching stock rods are between 7mm and 30mm longer than air-cooled
> units, which should give good low speed torque. If it were a push rod
> motor parts count would not be much greater than an inline?
>
> A stub attached to the flywheel end of the crank and ground with the
> mains to match a stock Continental front bearing, IMHO, would take
> care of prop loads.
> ======================
> Leon McAtee

What about using an American V8 crank to build a straight air cooled
four? All the ones I've seen apart had 2 rods per throw and that would
space things out more. Machining down the counter weights would be
required but it would still leave you with a very strong crank. A light
weight aluminum clamp that looked like a big end of a rod could be easy
to make to block off the extra oil ports.

Another option would be to take a lesson from the so called V6 VW that
is little more than a staggered in-line six. Staggering the cylinders
to make a shallow V4 would also improve cooling. The problems of uneven
firing order could be solve by using a distributorless ignition or a
pare of 2 cylinder distributors. This way you could choose any in-line
4 crank that is both cheap and common as dirt (like the Toyota 20R for
example...)

Tony

[jerry wass]

Anthony W wrote:
> wrote:
>
>> If I'm looking at this properly a standard VW water-cooled inline
>> crank (or most any similar 5 main bearing inline 4 crank) can be used
>> in a 90 deg. "V" 4. This would give plenty of room for fins. I think
>> all of the water-cooled VW cranks have 86mm or longer strokes and the
>> matching stock rods are between 7mm and 30mm longer than air-cooled
>> units, which should give good low speed torque. If it were a push rod
>> motor parts count would not be much greater than an inline?
>>
>> A stub attached to the flywheel end of the crank and ground with the
>> mains to match a stock Continental front bearing, IMHO, would take
>> care of prop loads.
>> ======================
>> Leon McAtee
>
> What about using an American V8 crank to build a straight air cooled
> four? All the ones I've seen apart had 2 rods per throw and that would
> space things out more. Machining down the counter weights would be
> required but it would still leave you with a very strong crank. A light
> weight aluminum clamp that looked like a big end of a rod could be easy
> to make to block off the extra oil ports.
>
> Another option would be to take a lesson from the so called V6 VW that
> is little more than a staggered in-line six. Staggering the cylinders
> to make a shallow V4 would also improve cooling. The problems of uneven
> firing order could be solve by using a distributorless ignition or a
> pare of 2 cylinder distributors. This way you could choose any in-line
> 4 crank that is both cheap and common as dirt (like the Toyota 20R for
> example...)
>
> Tony
Using a V-8 crankshaft would result in a weird firing order..(A 4 cyl
crank has 4 throws 180ºapart===-The V-8 has 4 throws spaced 90º apart.)
Jerry

[Anthony W]

Jerry Wass wrote:

> Using a V-8 crankshaft would result in a weird firing order..(A 4 cyl
> crank has 4 throws 180ºapart===-The V-8 has 4 throws spaced 90º apart.)
> Jerry

I guess that brings us back to the shallow V4 on a in-line 4 crank.
While it would have a slightly odd firing order too, it's nothing that
can't be worked around.

A 20 to 40 degree offset would be enough to allow for a little cooling
air to pass up the middle without making the firing order to weird.

Tony

[Veeduber[_2_]]

Lots of interesting ideas coming out. I've been doodling with them
using DeltaCAD. Trying to do an isometric of a V6 crankshaft is
enough to make you wanna go back to steam. Ditto for air-cooling.
Another ditto for valve trains.

Backing off, looking at the project from a different perspective, it
seems I'm more into details than basic concepts.

An exchange of messages with a fellow who actually works with the Lost
Foam process: when asked how fine I could go with details, he said to
go as fine as I like -- that producing the part was HIS task. Which
is kinda like money from home when you're trying to work out valve
train details. Some oil channels may have to be cleaned up with a
drill but the hole would still be there. Ditto for the fins. I spend
two hours on the thing before realizing I've got to do a lefty and a
righty.

[cavelamb[_2_]]

Veeduber wrote:
> Lots of interesting ideas coming out. I've been doodling with them
> using DeltaCAD. Trying to do an isometric of a V6 crankshaft is
> enough to make you wanna go back to steam. Ditto for air-cooling.
> Another ditto for valve trains.
>
> Backing off, looking at the project from a different perspective, it
> seems I'm more into details than basic concepts.
>

Big picture stuff?

Start with a way to hold the cylinders in place without pulling the case apart.

Second to the fin heat limits, that's the biggest problem with VWs.
The cylinder (and head) hold downs just thread into the case.

[Anthony W]

cavelamb wrote:

> Second to the fin heat limits, that's the biggest problem with VWs.
> The cylinder (and head) hold downs just thread into the case.

That problem is solved with over sized case savers. They bite into a
much larger amount of the case and spread the torque around to more of
the case. It's amazingly rare for one of these to pull out.

Tony

[cavelamb[_2_]]

Anthony W wrote:
> cavelamb wrote:
>
>> Second to the fin heat limits, that's the biggest problem with VWs.
>> The cylinder (and head) hold downs just thread into the case.
>
> That problem is solved with over sized case savers. They bite into a
> much larger amount of the case and spread the torque around to more of
> the case. It's amazingly rare for one of these to pull out.
>
> Tony

I've used those - just makes sense.
But if one is designing an engine rated at over 80 hp, it would be a
good thing to address...

[Anthony W]

cavelamb wrote:
> Anthony W wrote:
>> cavelamb wrote:
>>
>>> Second to the fin heat limits, that's the biggest problem with VWs.
>>> The cylinder (and head) hold downs just thread into the case.
>>
>> That problem is solved with over sized case savers. They bite into a
>> much larger amount of the case and spread the torque around to more of
>> the case. It's amazingly rare for one of these to pull out.
>>
>> Tony
>
> I've used those - just makes sense.
> But if one is designing an engine rated at over 80 hp, it would be a
> good thing to address...

An aluminum rather than a magnesium case and studs with a longer
threaded section would solve the problem. There are thousands if not
millions air cooled motorcycles and pulling a stud only happens when
some idiot over torques the stud. Even then, it's more common for the
stud to snap.

Tony

[jan olieslagers[_2_]]

Veeduber schreef:
> Lots of interesting ideas coming out.

Indeed, certainly to the eyes of this non-mechanic.
But few seem to answer your original search for an alternative for the
VW: a light engine of 40-60 HP, typical for a single seater.

Or what did I miss?
For that application, the Citroen 2-cylinder aircooled boxer seems one
of the rare alternatives; though it is smaller than the VW.

[Veeduber[_2_]]

On Jun 2, 9:20*am, jan olieslagers >
wrote:
> Veeduber schreef:
>
> > Lots of interesting ideas coming out.
>
> Indeed, certainly to the eyes of this non-mechanic.
> But few seem to answer your original search for an alternative for the
> VW: a light engine of 40-60 HP, typical for a single seater.
>
> Or what did I miss?
> For that application, the Citroen 2-cylinder aircooled boxer seems one
> of the rare alternatives; though it is smaller than the VW.
>----------------------------------------------------------------------------
"Or what did I miss?"

The Atlantic Ocean :-) The 2CV is an excellent engine, suitable for
single-seaters having low drag and a generous wing. But so few of
them were exported it is virtually unknown in the United States.

The engine received excellent coverage in auto magazines some years
ago when two engines were fitted to a vehicle which was then used as a
4WD for crossing the Sahara Desert.

Overhauling this engine is not for the inexperienced. It uses
specially shaped pistons which must be installed properly or the valve
will contact the piston, which usually results in a trashed engine.

-Bob

[jan olieslagers[_2_]]

Veeduber schreef:
> On Jun 2, 9:20 am, jan olieslagers >
> wrote:
>> Veeduber schreef:
>>
>>> Lots of interesting ideas coming out.
>> Indeed, certainly to the eyes of this non-mechanic.
>> But few seem to answer your original search for an alternative for the
>> VW: a light engine of 40-60 HP, typical for a single seater.
>>
>> Or what did I miss?
>> For that application, the Citroen 2-cylinder aircooled boxer seems one
>> of the rare alternatives; though it is smaller than the VW.
>> ----------------------------------------------------------------------------
> "Or what did I miss?"
>
> The Atlantic Ocean :-)

OK Bob, thanks for the reminder...
Still, you asked for a 40-60 HP engine
and all and sundry came up with 80-100 hp ideas,
that's my concern now.

Seems the US market has a hole, indeed, between
the 30-40 HP range and 80HP upwards.
Europe has _some_ offer there,
but not too much and indeed each with its limitations.
And we badly want information about Asian offerings,
as you already pointed out before.

[cavelamb[_2_]]

jan olieslagers wrote:
> Veeduber schreef:
>> On Jun 2, 9:20 am, jan olieslagers >
>> wrote:
>>> Veeduber schreef:
>>>
>>>> Lots of interesting ideas coming out.
>>> Indeed, certainly to the eyes of this non-mechanic.
>>> But few seem to answer your original search for an alternative for the
>>> VW: a light engine of 40-60 HP, typical for a single seater.
>>>
>>> Or what did I miss?
>>> For that application, the Citroen 2-cylinder aircooled boxer seems one
>>> of the rare alternatives; though it is smaller than the VW.
>>> ----------------------------------------------------------------------------
>>>
>> "Or what did I miss?"
>>
>> The Atlantic Ocean :-)
>
> OK Bob, thanks for the reminder...
> Still, you asked for a 40-60 HP engine
> and all and sundry came up with 80-100 hp ideas,
> that's my concern now.
>
> Seems the US market has a hole, indeed, between
> the 30-40 HP range and 80HP upwards.
> Europe has _some_ offer there,
> but not too much and indeed each with its limitations.
> And we badly want information about Asian offerings,
> as you already pointed out before.



Rotax - 503 or 582 (618).

Yes, they are two stroke engines.

When installed and operated correctly they are very reliable.


They run turbine smooth, and the power to weight ratio is tops.

[Veeduber[_2_]]

On Jun 2, 11:41*am, jan olieslagers >
wrote:

> Still, you asked for a 40-60 HP engine
> and all and sundry came up with 80-100 hp ideas,
> that's my concern now.
> --------------------------------------------------------------------------------------------------------------

Dear Jan,

Yes. That is always the case on the internet, where the reader must
sort the wheat from the chaff.

The thread originated with Stealth Pilot (an Australian) pointing out
the dearth of Volkswagen engines in his country or locale, leaving a
hole for LOW COST engines suitable for conversion to power-plants
suitable for use in home-built airplanes. He implied that a 40
horsepower engine would fill the needs of the home-builder, probably
because that is about all a converted VW is good for if you want an
acceptable mean-time before overhaul. I then jumped in and said this
problem was not unique to Australia but would soon be felt world-wide,
especially as more home-builders in S.E. Asia and China begin to
stretch their home-built wings, suggesting we should try to come up
with a solution in the form of an affordable engine in that power-
range.

>-----------------------------------------------------------------------------------------------------
>
> Seems the US market has a hole, indeed, between
> the 30-40 HP range and 80HP upwards.
> Europe has _some_ offer there,
> but not too much and indeed each with its limitations.
> And we badly want information about Asian offerings,
> as you already pointed out before.
>
> ----------------------------------------------------------------------------------------------------

Home-builders ere in the States are unlikely to feel there is a gap so
long as the Corvair remains in good supply. Nor is their a shortage
world-wide if we are willing to consider heavier, liquid-cooled
engines. Unfortunately such engines are best suited for larger
airframes or fairly complex biplanes, typically beyond the means of
most first-time home-builders, which lead to my wondering about what
engines might be available from TATA, the GM of India, or from the
sleeping tiger of Chinese industrial might. I feel it is important
for us to identify engines suitable for conversion and to do whatever
we can to facilitate grass-roots aviation in those countries.

-R.S.Hoover

[Morgans[_2_]]

"cavelamb" > wrote
>
> Rotax - 503 or 582 (618).

> When installed and operated correctly they are very reliable.

When installed and operated correctly they are very reliable.

Say that again.
When installed and operated correctly they are very reliable.

Again.
When installed and operated correctly they are very reliable. When
installed and operated correctly they are very reliable. When installed and
operated correctly they are very reliable.

Therein lies the problem. When.
When, When, When.

Too often they are not operated correctly, partially because they are too
many different ways to screw up. When goes all to hell, then.

Logically then, the sentence becomes: When _NOT_ installed and operated
correctly they are _NOT_ very reliable.

In my opinion, no two strokes belong in any plane that does not fly so
slowly that crashes into any object are not survivable.
--
Jim in NC

[Brian Whatcott]

Morgans wrote:
> "cavelamb" > wrote
>> Rotax - 503 or 582 (618).
>
>> When installed and operated correctly they are very reliable.
>
> When installed and operated correctly they are very reliable.
>
> Say that again.
> When installed and operated correctly they are very reliable.
>
> Again.
> When installed and operated correctly they are very reliable. When
> installed and operated correctly they are very reliable. When installed and
> operated correctly they are very reliable.
>
> Therein lies the problem. When.
> When, When, When.
>
> Too often they are not operated correctly, partially because they are too
> many different ways to screw up. When goes all to hell, then.
>
> Logically then, the sentence becomes: When _NOT_ installed and operated
> correctly they are _NOT_ very reliable.
>
> In my opinion, no two strokes belong in any plane that does not fly so
> slowly that crashes into any object are not survivable.


Now HERE'S an interesting thread.
I have seen ultralights go quiet, crash and the tales of resulting dire
injury. But I have no insight into correctly handling the aero 2-stroke.
What constitutes "install and operate correctly."
You could save somebody a whole spoiled day if you will tell.

Thanks

Brian W

[cavelamb[_2_]]

Brian Whatcott wrote:
> Morgans wrote:
>> "cavelamb" > wrote
>>> Rotax - 503 or 582 (618).
>>
>>> When installed and operated correctly they are very reliable.
>>
>> When installed and operated correctly they are very reliable.
>>
>> Say that again.
>> When installed and operated correctly they are very reliable.
>>
>> Again.
>> When installed and operated correctly they are very reliable. When
>> installed and operated correctly they are very reliable. When
>> installed and operated correctly they are very reliable.
>>
>> Therein lies the problem. When.
>> When, When, When.
>>
>> Too often they are not operated correctly, partially because they are
>> too many different ways to screw up. When goes all to hell, then.
>>
>> Logically then, the sentence becomes: When _NOT_ installed and
>> operated correctly they are _NOT_ very reliable.
>>
>> In my opinion, no two strokes belong in any plane that does not fly so
>> slowly that crashes into any object are not survivable.
>
>
> Now HERE'S an interesting thread.
> I have seen ultralights go quiet, crash and the tales of resulting dire
> injury. But I have no insight into correctly handling the aero 2-stroke.
> What constitutes "install and operate correctly."
> You could save somebody a whole spoiled day if you will tell.
>
> Thanks
>
> Brian W

Installation and operation:
http://www.ultralightnews.ca/rotax503/rotax2strokepdf/503installationmanual.pdf

Maintenance Schedule:
http://www.ultralightnews.ca/rotax503/rotax2strokepdf/503maintenancemanual.pdf

As you said...
While not installed or operated correctly ANY engine will fail.

Do you think a home made engine will be any better?

[Veeduber[_2_]]

On Jun 3, 5:51*am, cavelamb > wrote:
While not installed or operated correctly ANY engine will fail.
>
> Do you think a home made engine will be any better?
>-----------------------------------------------------------------------

It is only 'home-made' in the same sense that the Aero-Vee is home-
made. And you don't have to be a rocket-scientist to do better than
that.

-R.S.Hoover

[cavelamb[_2_]]

Veeduber wrote:
> On Jun 3, 5:51 am, cavelamb > wrote:
> While not installed or operated correctly ANY engine will fail.
>> Do you think a home made engine will be any better?
>> -----------------------------------------------------------------------
>
> It is only 'home-made' in the same sense that the Aero-Vee is home-
> made. And you don't have to be a rocket-scientist to do better than
> that.
>
> -R.S.Hoover

I dunno, Robert.
I mean I understand your position.

But the only fatality we ever had was due to a home brew VW.

[Gerry van Dyk]

Forgive me for butting in, I have no experience or credibility on the
subject, but doesn't the HKS-700E fit right in this category? A
currently-in-production, honest-to-goodness, no-kidding, real airplane
engine; 60 HP, 100-odd pound 4-stoke twin cylinder, dual ignition,
integral gearbox with torsional shock apsorber and optional gear
ratios. I realize many will hack and wheeze at $10K price tag, but in
the world of airplane engines isn't this dirt cheap?

What are the fundamental problems with the HKS that it isn't one of
the options being discussed?

Gerry

[Brian Whatcott]

Gerry van Dyk wrote:
> Forgive me for butting in, I have no experience or credibility on the
> subject, but doesn't the HKS-700E fit right in this category? A
> currently-in-production, honest-to-goodness, no-kidding, real airplane
> engine; 60 HP, 100-odd pound 4-stoke twin cylinder, dual ignition,
> integral gearbox with torsional shock apsorber and optional gear
> ratios. I realize many will hack and wheeze at $10K price tag, but in
> the world of airplane engines isn't this dirt cheap?
>
> What are the fundamental problems with the HKS that it isn't one of
> the options being discussed?
>
> Gerry

Briefly, the homebuilder would be overjoyed to find a device that's
dirt-cheap, rock-solid, as reliable as taxes, and oh: pretty would be nice.
That's a hard prescription to fill, but the faithful keep thinking
and looking. $2K would be nice - $10K isn't.

Brian W

[cavelamb[_2_]]

Gerry van Dyk wrote:
> Forgive me for butting in, I have no experience or credibility on the
> subject, but doesn't the HKS-700E fit right in this category? A
> currently-in-production, honest-to-goodness, no-kidding, real airplane
> engine; 60 HP, 100-odd pound 4-stoke twin cylinder, dual ignition,
> integral gearbox with torsional shock apsorber and optional gear
> ratios. I realize many will hack and wheeze at $10K price tag, but in
> the world of airplane engines isn't this dirt cheap?
>
> What are the fundamental problems with the HKS that it isn't one of
> the options being discussed?
>
> Gerry


I can't answer you on that, Gerry, because I've never even seen one
much less actually flown it.

But the numbers sure look good.

The Rotax 912 isn't much more than that, and it's rated at 80 hp.

Then there is the little Jabaru (60?)

The last VW I built was a fully equipped 2180.
(208 pounds with starter, alternator, single mag, mount, etc)
It cost about $5k, when all was said and done.
It was still a 40 horse motor.

[Stealth Pilot[_2_]]

On Tue, 2 Jun 2009 19:59:09 -0700 (PDT), Veeduber
> wrote:

>On Jun 2, 11:41*am, jan olieslagers >
>wrote:
>
>> Still, you asked for a 40-60 HP engine
>> and all and sundry came up with 80-100 hp ideas,
>> that's my concern now.
>> --------------------------------------------------------------------------------------------------------------
>
>Dear Jan,
>
>Yes. That is always the case on the internet, where the reader must
>sort the wheat from the chaff.
>
>The thread originated with Stealth Pilot (an Australian) pointing out
>the dearth of Volkswagen engines in his country or locale, leaving a
>hole for LOW COST engines suitable for conversion to power-plants
>suitable for use in home-built airplanes. He implied that a 40
>horsepower engine would fill the needs of the home-builder, probably
>because that is about all a converted VW is good for if you want an
>acceptable mean-time before overhaul. I then jumped in and said this
>problem was not unique to Australia but would soon be felt world-wide,
>especially as more home-builders in S.E. Asia and China begin to
>stretch their home-built wings, suggesting we should try to come up
>with a solution in the form of an affordable engine in that power-
>range.
>
>>-----------------------------------------------------------------------------------------------------
>>
>> Seems the US market has a hole, indeed, between
>> the 30-40 HP range and 80HP upwards.
>> Europe has _some_ offer there,
>> but not too much and indeed each with its limitations.
>> And we badly want information about Asian offerings,
>> as you already pointed out before.
>>
>> ----------------------------------------------------------------------------------------------------
>
>Home-builders ere in the States are unlikely to feel there is a gap so
>long as the Corvair remains in good supply. Nor is their a shortage
>world-wide if we are willing to consider heavier, liquid-cooled
>engines. Unfortunately such engines are best suited for larger
>airframes or fairly complex biplanes, typically beyond the means of
>most first-time home-builders, which lead to my wondering about what
>engines might be available from TATA, the GM of India, or from the
>sleeping tiger of Chinese industrial might. I feel it is important
>for us to identify engines suitable for conversion and to do whatever
>we can to facilitate grass-roots aviation in those countries.
>
>-R.S.Hoover

bang on the money Bob.
Stealth Pilot

[Stealth Pilot[_2_]]

On Sat, 30 May 2009 10:11:39 -0500, Charles Vincent
> wrote:

>Veeduber wrote:
>> On May 29, 3:12 pm, Charles Vincent > wrote:
>>
>>> They do have an OHV version I believe. At the RPM's these engines run
>>> at i.e. direct drive prop, I am not sure the L head is that much of a
>>> compromise.
>>> ----------------------------------------------------------------------------------------
>>
>> All of the Pobjoy's were geared, OHV engines. They produced 80hp @
>> 3300 rpm (prop speed of 1400rpm). Weight was 130 lbs.
>>
>> -R.S.Hoover
>>
>
>I was referring to the HCI Radials which are ungeared. I have seen the
> Pobjoy. I have collected everything I can get my hands on with regard
>to small radial engines. I have even managed to find factory blueprints
>for parts of the Kinner and a Leblonde. No prints sadly for the Pobjoy,
>just some contemporaneous technical reviews that do have three views of
>the engine. There was a Pobjoy on display in a museum outside San Jose,
>but that is a trek from your 20.
>
>Charles

I will post some scanned photos of a sectioned pobjoy on
alt.binaries.pictures.aviation in the near future.

I thought I had cracked the problem when I discovered that the Pobjoy
R was made under licence by Walter as the Walter Mira.
an email to Walter caused some searching among the old retired
employees and one was able to confirm that the tooling and all the
drawings were destroyed in WW2 when the factory was the target of an
allied bombing raid.

bugger the war!
Stealth Pilot

[Gerry van Dyk]

Yes indeed, striving for the (all but) impossible is always a noble
task.
I'm in a completely different frame of mind, I'm concentrating on
building my first airplane and working out a powerplant isn't one of
the new experiences I want to tackle, and getting a pilot's license
will probably be hand along the way as well. (Yep, I'm doing it
backwards. ;^)

Just to be a devil's advocate for a moment, if one were to add $1 per
hour for all the time used thinking about it, plus all the actual
money spent testing out ideas, that $2000 engine might be a lot closer
to $10K than anyone is willing to admit. Nonetheless "Because I want
to" is a phrase that has no intrinsic value, and yet is worth a
million bucks to whoever says it.

I'll continue to follow this thread with interest, please return to
your regularly scheduled brainstorming.

Cheers
Gerry

>
> Briefly, the homebuilder would be overjoyed to find a device that's
> dirt-cheap, rock-solid, as reliable as taxes, and oh: pretty would be nice.
> * * * That's a hard prescription to fill, but the faithful keep thinking
> and looking. $2K would be nice - $10K isn't.
>
> Brian W

[Peter Dohm]

Gerry,

I agree with you about the amount of time being wasted.

Especially, I suspect that the series of threads have worked their way
around to a search for a "traditional" direct drive "real" airplane
engine--with an implied resolution to build one if it can not be purchased
new at an unrealistic discount.

Actually, there have been any number of successfull installations of higher
reving engines with multiple v-belt reduction systems. They are probably
not especially energy efficient, and the belts are quickly destroyed if the
propeller windmills in flight with the engine stopped; but they are a cheap
and light weight way to get the job done and are easily inspected.

Personally, I really don't "like" that solution; but it is well proven for
relatively low power; but cheap and easy to inspect can save you a lot more
than a little lower friction for personal use of a small sport aircraft.
So, I would have to seriously consider that as my solution for less than 80
horsepower if I needed an engine at the present time.

As you say, it has become a nearly complete waste of time, and I expect my
own contributions to be few and far between for the forseeable future.

Peter


"Gerry van Dyk" > wrote in message
...
Yes indeed, striving for the (all but) impossible is always a noble
task.
I'm in a completely different frame of mind, I'm concentrating on
building my first airplane and working out a powerplant isn't one of
the new experiences I want to tackle, and getting a pilot's license
will probably be hand along the way as well. (Yep, I'm doing it
backwards. ;^)

Just to be a devil's advocate for a moment, if one were to add $1 per
hour for all the time used thinking about it, plus all the actual
money spent testing out ideas, that $2000 engine might be a lot closer
to $10K than anyone is willing to admit. Nonetheless "Because I want
to" is a phrase that has no intrinsic value, and yet is worth a
million bucks to whoever says it.

I'll continue to follow this thread with interest, please return to
your regularly scheduled brainstorming.

Cheers
Gerry

>
> Briefly, the homebuilder would be overjoyed to find a device that's
> dirt-cheap, rock-solid, as reliable as taxes, and oh: pretty would be
> nice.
> That's a hard prescription to fill, but the faithful keep thinking
> and looking. $2K would be nice - $10K isn't.
>
> Brian W

[Morgans[_2_]]

"Peter Dohm" > wrote in message
...
> Gerry,
>
> I agree with you about the amount of time being wasted.
>
> Especially, I suspect that the series of threads have worked their way around
> to a search for a "traditional" direct drive "real" airplane engine--with an
> implied resolution to build one if it can not be purchased new at an
> unrealistic discount.
>
> Actually, there have been any number of successfull installations of higher
> reving engines with multiple v-belt reduction systems. They are probably not
> especially energy efficient, and the belts are quickly destroyed if the
> propeller windmills in flight with the engine stopped; but they are a cheap
> and light weight way to get the job done and are easily inspected.
>
> Personally, I really don't "like" that solution; but it is well proven for
> relatively low power; but cheap and easy to inspect can save you a lot more
> than a little lower friction for personal use of a small sport aircraft. So, I
> would have to seriously consider that as my solution for less than 80
> horsepower if I needed an engine at the present time.
>
> As you say, it has become a nearly complete waste of time, and I expect my own
> contributions to be few and far between for the forseeable future.

The more I think about it, I think the Harley is the perfect choice. High HP,
air cooled, available from crashed bikes, built with a separate crankcase,
designed with a belt drive to be used, many sizes available.
--
Jim in NC

[vaughn]

"Morgans" > wrote in message
...
>
> The more I think about it, I think the Harley is the perfect choice. High
> HP, air cooled, available from crashed bikes, built with a separate
> crankcase, designed with a belt drive to be used, many sizes available.

I am not sure if the Harley engine is perfect or not, but to your list I
would add that virtually every part and even brand new whole "clone" Harley
engines are available from several sources in addition to Harley Davidson
itself.

Not cheap, not so available, but what about the various BMW motorcycle
engines?

Vaughn

[Stealth Pilot[_2_]]

On Fri, 05 Jun 2009 01:08:03 GMT, "vaughn"
> wrote:

>
>"Morgans" > wrote in message
...
>>
>> The more I think about it, I think the Harley is the perfect choice. High
>> HP, air cooled, available from crashed bikes, built with a separate
>> crankcase, designed with a belt drive to be used, many sizes available.
>
>I am not sure if the Harley engine is perfect or not, but to your list I
>would add that virtually every part and even brand new whole "clone" Harley
>engines are available from several sources in addition to Harley Davidson
>itself.
>
>Not cheap, not so available, but what about the various BMW motorcycle
>engines?
>
>Vaughn
>

bmw engines need only a modified rotax gear head fitted to them to be
usable.

[Gerry van Dyk]

On Jun 4, 10:30*am, "Peter Dohm" > wrote:
> Gerry,
>
> I agree with you about the amount of time being wasted.
>
> Especially, I suspect that the series of threads have worked their way
> around to a search for a "traditional" direct drive "real" airplane
> engine--with an implied resolution to build one if it can not be purchased
> new at an unrealistic discount.

Peter, I certainly want to be more careful about calling it "wasted
time". If one succeeds the time is certainly not wasted is it? My
only real point is to caution everyone about how much that "Cheap /
Inexpensive" engine actually cost in real life. I'm sure that there's
been more than one occasion where that engine proved to cost more than
an off-the-shelf airplane engine. All the Eggenfellners, Vestas,
Aerovees, Real World Solutions and other conversion engines of the
world started with a guy and an idea. No-one who gives such a
conversion a swing need justify to us on the sideline why they're
doing it.

Cheers
Gerry

[Peter Dohm]

"Gerry van Dyk" > wrote in message
...
>On Jun 4, 10:30 am, "Peter Dohm" > wrote:
>> Gerry,
>>
>> I agree with you about the amount of time being wasted.
>>
>> Especially, I suspect that the series of threads have worked their way
> > around to a search for a "traditional" direct drive "real" airplane
> > engine--with an implied resolution to build one if it can not be
> > purchased
>> new at an unrealistic discount.
>
> Peter, I certainly want to be more careful about calling it "wasted
> time". If one succeeds the time is certainly not wasted is it? My
> only real point is to caution everyone about how much that "Cheap /
> Inexpensive" engine actually cost in real life. I'm sure that there's
> been more than one occasion where that engine proved to cost more than
> an off-the-shelf airplane engine. All the Eggenfellners, Vestas,
> Aerovees, Real World Solutions and other conversion engines of the
> world started with a guy and an idea. No-one who gives such a
> conversion a swing need justify to us on the sideline why they're
> doing it.
>
> Cheers
> Gerry
>
Exactly right. The "fun factor" of making your own design, or adaptation,
work well has to be part of the equation.

By the way, I must admit that I was at least partially wrong in my advocacy
of a multiple v-belt reduction drive. The darned things can loose a lot of
traction when wet, so that will require a lot more thought.

Peter