Casting Four Individual VW Heads

[[email protected]]

To All:

It appears that personalities and other factors overwhelmed the
subject that I thought it best to start anew.

One of those other factors is my physical condition -- more
specifically, the amount of pain I have to deal with and the
limitations placed on me by the physicians, such as limiting the
amount I can lift to about 25 lbs. Cheating isn't wise since I'm
liable to crush another vertebrae. Increasing my pain medication is
also unwise, since it causes to pass out... only to have the pain wake
me up due to some crazy angle of my neck or back... which causes me to
reach for the pain pills AGAIN... round & round we go...

----------------------------------------------------------------------------------------------------

The objective is to produce TWO unique castings -- one forward, one
aft -- for the two barrels on each side of the VW engine.

Volkswagen presently uses ONE casting, flipping it end-for-end when
used on the opposite bank of cylinders. By splitting the single head
into two individual castings, we can move the exhaust stack to a new
position that is lower than the outlet on the present head, thus
allowing MORE FIN AREA to be cast onto the ends of the individual
heads.

Since these heads are not for vehicles, there is no limitation on the
height of the fins. If the heads WERE for bugs or buses they would
have to fit UNDER the stock tin-ware, reducing the maximum fin height
to about one inch.

Based on the parting-line flash of new, stock heads, they are cast
using two molds. To cast INDIVIDUAL heads it will take at least THREE
molds of FOUR different types. Anyone having actual experience with
finned aluminum castings is encouraged to offer their opinion.

I have drawings & photos of VW heads that I'll be happy to post to
some address where they might be available to all -- and would
appreciate comments as to where such a place might be. But no
Bluesky, please. I'm trying to solve a problem; I've no interest in
creating another Chat Room.

-Bob Hoover

[Copperhead]

On Jan 16, 5:08*pm, " > wrote:
> To All:
>
> It appears that personalities and other factors overwhelmed the
> subject that I thought it best to start anew.
>
> One of those other factors is my physical condition -- more
> specifically, the amount of pain I have to deal with and the
> limitations placed on me by the physicians, such as limiting the
> amount I can lift to about 25 lbs. *Cheating isn't wise since I'm
> liable to crush another vertebrae. *Increasing my pain medication is
> also unwise, since it causes to pass out... only to have the pain wake
> me up due to some crazy angle of my neck or back... which causes me to
> reach for the pain pills AGAIN... round & round we go...
>
> ---------------------------------------------------------------------------*-------------------------
>
> The objective is to produce TWO unique castings -- one forward, one
> aft -- for the two barrels on each side of the VW engine.
>
> Volkswagen presently uses ONE casting, flipping it end-for-end when
> used on the opposite bank of cylinders. *By splitting the single head
> into two individual castings, we can move the exhaust stack to a new
> position that is lower than the outlet on the present head, thus
> allowing MORE FIN AREA to be cast onto the ends of the individual
> heads.
>
> Since these heads are not for vehicles, there is no limitation on the
> height of the fins. *If the heads WERE for bugs or buses they would
> have to fit UNDER the stock tin-ware, reducing the maximum fin height
> to about one inch.
>
> Based on the parting-line flash of new, stock heads, they are cast
> using two molds. *To cast INDIVIDUAL heads it will take at least THREE
> molds of FOUR different types. *Anyone having actual experience with
> finned aluminum castings is encouraged to offer their opinion.
>
> I have drawings & photos of VW heads that I'll be happy to post to
> some address where they might be available to all -- and would
> appreciate comments as to where such a place might be. *But no
> Bluesky, please. *I'm trying to solve a problem; I've no interest in
> creating another Chat Room.
>
> -Bob Hoover

Bob,
I have done some experimental metal casting work, but nothing to the
extent you’re proposing; however, such a concept is within reason.
Quite rightly the mold design and preparation are the most significant
aspect of this project, once made though and good foundry can produce
the castings. The end user can than do their own clean up milling work
or if desired such work may be done by the seller. Beyond this I’ll
honor your request for no blue sky flights of fancy, but I hope you
consider posting your drawings on your blog.
Regards
Joe S.

[[email protected]]

On Jan 17, 8:15*am, Copperhead > wrote:
> Beyond this I’ll
> honor your request for no blue sky flights of fancy, but I hope you
> consider posting your drawings on your blog.
--------------------------------------------------------------------------------------

Yo, Joe.

Thank you. But there's Blue Sky... then there's bluesky, in which a
nine-page article is based on a 'minor detail' such as steel which
happens to float. Or a Gasoline Pill. Or... you know what I mean. I
am MORE than willing to go Blue Sky when it involves nothing more than
nudging Mother Nature in the right direction... such as finding the
fellow who is casting those Aluminum Crankcases, and finding the
Chinese shop which is casting those remarkable crankshafts, and buying
them lunch, with the object being a crank that's about five inches
longer and the crankcase to house it. Because we simply don't have
enough bearing area to pull more than about fifty ponys out of the VW
crank for a MINIMUM of 1000 hours. But there IS enough bearing area
on... what? I know they're out there -- I've seen their shells in the
trash out behind the DeSoto dealer's shop. (Yeah, it's been a
while... But the point is that the BEARING means there's a ROD that
will fit it. And I'm all for THAT brand of Blue Sky.)

If all goes well, this afternoon -- Saturday the 17th of January,
2009, Steve Bennett and I will sit ourselves down across the table
from each other and come up with the Master Plan for the Invasion of
Homebuilt Land.

I will be wearing my Lucky Shirt.

There are New Batteries in my camera.

There will be at least one Calculator on the table.

If you can think of anything I've forgotten, include it now.

-Bob

[Fred the Red Shirt]

On Jan 16, 6:08*pm, " > wrote:
>
> ...
>
> The objective is to produce TWO unique castings -- one forward, one
> aft -- for the two barrels on each side of the VW engine.
>
> ...
>
> Since these heads are not for vehicles, there is no limitation on the
> height of the fins. *If the heads WERE for bugs or buses they would
> have to fit UNDER the stock tin-ware, reducing the maximum fin height
> to about one inch.
>
> Based on the parting-line flash of new, stock heads, they are cast
> using two molds. *To cast INDIVIDUAL heads it will take at least THREE
> molds of FOUR different types. *Anyone having actual experience with
> finned aluminum castings is encouraged to offer their opinion.
> ...
>

My experience is not with casting but with fin design. Fins that
are longer than necessary will reduce the cooling.

Think of it this way: As you move along from root to tip the
temperature in the fin drops. If it drops to the same as
the air temperature before you reach the tip, all of the fin
between that point and the tip is wasted. Actually worse
than wasted as cooling air passing over that outer part of
the fin doesn't cool anything, as you're wasting air too.

That's an extreme situation, but the point is that there is an
optimum length for cooling fins given a fixed massflow of
cooling air.

And as mentioned before, tapering the fins in thickness from
root to tip helps to maximize the cooling and minimize the
weight too.

--

FF

[Copperhead]

On Jan 17, 5:17*pm, Fred the Red Shirt >
wrote:
> On Jan 16, 6:08*pm, " > wrote:
>
>
>
>
>
>
>
> > ...
>
> > The objective is to produce TWO unique castings -- one forward, one
> > aft -- for the two barrels on each side of the VW engine.
>
> > ...
>
> > Since these heads are not for vehicles, there is no limitation on the
> > height of the fins. *If the heads WERE for bugs or buses they would
> > have to fit UNDER the stock tin-ware, reducing the maximum fin height
> > to about one inch.
>
> > Based on the parting-line flash of new, stock heads, they are cast
> > using two molds. *To cast INDIVIDUAL heads it will take at least THREE
> > molds of FOUR different types. *Anyone having actual experience with
> > finned aluminum castings is encouraged to offer their opinion.
> > ...
>
> My experience is not with casting but with fin design. *Fins that
> are longer than necessary will reduce the cooling.
>
> Think of it this way: *As you move along from root to tip the
> temperature in the fin drops. *If it drops to the same as
> the air temperature before you reach the tip, all of the fin
> between that point and the tip is wasted. *Actually worse
> than wasted as cooling air passing over that outer part of
> the fin doesn't cool *anything, as you're wasting air too.
>
> That's an extreme situation, but the point is that there is an
> optimum length for cooling fins given a fixed massflow of
> cooling air.
>
> And as mentioned before, tapering the fins in thickness from
> root to tip helps to maximize the cooling and minimize the
> weight too.
>
> --
>
> FF- Hide quoted text -
>
> - Show quoted text -

Without a doubt the concept of a longer case and crank shaft for
increased bearing surface coupled with an improved head casting with
relocated exhaust valves and increased fin space is long past due. The
Corvair aircraft engine has now seen the introduction of a fifth
bearing surface as well as forged crankshafts becoming available, but
still in question as to long term reliability. Me, I’d be more than
willing to purchase improved VW “aircraft” engine parts for a build
project. Without a doubt others would to as such an engine would be
fantastic.

Joe S.

[[email protected]]

> And as mentioned before, tapering the fins in thickness from
> root to tip helps to maximize the cooling and minimize the
> weight too.
--------------------------------------------------------------------------------------------------

It's not just a 'nice-to-have' feature, the draft or taper is an
absolute necessity, first for successful casting, then for EFFICIENT
cooling. Transfer of heat to the atmosphere causes the air to
expand. If the air channels are not tapered the 'fatter' air quickly
REDUCES air-flow through the fins and the engine begins to overheat.

-Bob

[Stealth Pilot[_2_]]

On Sat, 17 Jan 2009 10:18:42 -0800 (PST), "
> wrote:


>
>If all goes well, this afternoon -- Saturday the 17th of January,
>2009, Steve Bennett and I will sit ourselves down across the table
>from each other and come up with the Master Plan for the Invasion of
>Homebuilt Land.
>

why does steve bennett's name ring a bell? is he 'great planes'?

[Copperhead]

On Jan 18, 4:00*am, Stealth Pilot >
wrote:
> On Sat, 17 Jan 2009 10:18:42 -0800 (PST), "
>
> > wrote:
>
> >If all goes well, this afternoon -- Saturday the 17th of January,
> >2009, Steve Bennett and I will sit ourselves down across the table
> >from each other and come up with the Master Plan for the Invasion of
> >Homebuilt Land.
>
> why does steve bennett's name ring a bell? is he 'great planes'?

Yes, that's the man, he's already marketing a great deal of VW engine
kit option's for aircraft. If we're really lucky enough perhap's he'll
be willing to do a test marketing run on improved VW head's and such.

[[email protected]]

On Jan 18, 2:00*am, Stealth Pilot >
wrote:

> why does steve bennett's name ring a bell? is he 'great planes'?
-----------------------------------------------------------------------------------------------

Yes, unfortunately we failed to connect -- I was waiting for him to
call, while he had already gone to the restaurant I'd suggested and
was waiting for me there. After a couple of hours he called to say
he'd run out of time. And there I was, thinking he was still in San
Diego.

-Bob

[Maxwell[_2_]]

"Fred the Red Shirt" > wrote in message
...
On Jan 16, 6:08 pm, " > wrote:
>
> ...
>
> The objective is to produce TWO unique castings -- one forward, one
> aft -- for the two barrels on each side of the VW engine.
>
> ...
>
> Since these heads are not for vehicles, there is no limitation on the
> height of the fins. If the heads WERE for bugs or buses they would
> have to fit UNDER the stock tin-ware, reducing the maximum fin height
> to about one inch.
>
> Based on the parting-line flash of new, stock heads, they are cast
> using two molds. To cast INDIVIDUAL heads it will take at least THREE
> molds of FOUR different types. Anyone having actual experience with
> finned aluminum castings is encouraged to offer their opinion.
> ...
>

My experience is not with casting but with fin design. Fins that
are longer than necessary will reduce the cooling.

Think of it this way: As you move along from root to tip the
temperature in the fin drops. If it drops to the same as
the air temperature before you reach the tip, all of the fin
between that point and the tip is wasted. Actually worse
than wasted as cooling air passing over that outer part of
the fin doesn't cool anything, as you're wasting air too.

That's an extreme situation, but the point is that there is an
optimum length for cooling fins given a fixed massflow of
cooling air.

And as mentioned before, tapering the fins in thickness from
root to tip helps to maximize the cooling and minimize the
weight too.

--

FF

------------------------------------------------------------------------------------------------

Agreed. So considering the thermal properties of something like 356
aluminum, what would be the most efficient geometry for cooling a cylinder
head? Length, pitch, taper, etc.

[[email protected]]

Once you cast the heads unfinned with the ports laid out in the desired
configuration, what would prevent you from using an electroplating
method to grow the fins out, with the air gap pattern between the fins
blocked out to prevent metal deposition? Then grow them out to the
extent desired, or larger and grind them down based on testing.

A.L.
Phoenix

[[email protected]]

On Jan 18, 9:41*am, " > wrote:
> On Jan 18, 2:00*am, Stealth Pilot >
> wrote:
>
> > why does steve bennett's name ring a bell? is he 'great planes'?
>
> -----------------------------------------------------------------------------------------------
>
> Yes, unfortunately we failed to connect
-------------------------------------------------------------------------------------------------

We connected today. Had a very nice visit, including a tour of the
shop, varmint gunnery program, engine building and hummingbird
offensives. Given a bit more time we might have touched on
airplanes :-)

-Bob

[[email protected]]

On Jan 16, 4:08*pm, " > wrote:

> Based on the parting-line flash of new, stock heads, they are cast
> using two molds. *To cast INDIVIDUAL heads it will take at least THREE
> molds of FOUR different types. *Anyone having actual experience with
> finned aluminum castings is encouraged to offer their opinion.
>
> -Bob Hoover

I'm still of the opinion that lost foam is the way to go. To this end
I have been trying to get my hands on some more UN-expanded styrene
beads. (Bean bag foam doesn't have any puffy stuff left in it) Seems
that EPS beads are no longer available in small retail quantities as
they have been deemed hazardous by some alphabet bureaucrat somewhere
and the result is the hazmat fee is more than the beads. That and I
read some duck hunter blew up his kitchen.

If someone knows of a source I'm interested. I'd prefer to not have
to buy a whole pallet load, but if that is what it takes to get it
here.............................
========================
Leon McAtee

[Anthony W]

wrote:

> I'm still of the opinion that lost foam is the way to go. To this end
> I have been trying to get my hands on some more UN-expanded styrene
> beads. (Bean bag foam doesn't have any puffy stuff left in it) Seems
> that EPS beads are no longer available in small retail quantities as
> they have been deemed hazardous by some alphabet bureaucrat somewhere
> and the result is the hazmat fee is more than the beads. That and I
> read some duck hunter blew up his kitchen.
>
> If someone knows of a source I'm interested. I'd prefer to not have
> to buy a whole pallet load, but if that is what it takes to get it
> here.............................
> ========================
> Leon McAtee

Where's the company that sells the stuff? Maybe one of us are near them
and would be wiling to pick them up for you and ship them to you in a
plain brown wrapper...

Tony

[[email protected]]

On Jan 19, 10:59*pm, Anthony W > wrote:

> Where's the company that sells the stuff?

That's the trick. I don't know, other than Dow and some other primary
manufacturers. So far the e-mails have either bounced or come back
"sorry can't help"

*>Maybe one of us are near them
> and would be wiling to pick them up for you and ship them to you in a
> plain brown wrapper...
>
> Tony
==========================
Leon McAtee

[Tim Ward[_1_]]

> wrote in message
...
On Jan 16, 4:08 pm, " > wrote:

> Based on the parting-line flash of new, stock heads, they are cast
> using two molds. To cast INDIVIDUAL heads it will take at least THREE
> molds of FOUR different types. Anyone having actual experience with
> finned aluminum castings is encouraged to offer their opinion.
>
> -Bob Hoover

I'm still of the opinion that lost foam is the way to go. To this end
I have been trying to get my hands on some more UN-expanded styrene
beads. (Bean bag foam doesn't have any puffy stuff left in it) Seems
that EPS beads are no longer available in small retail quantities as
they have been deemed hazardous by some alphabet bureaucrat somewhere
and the result is the hazmat fee is more than the beads. That and I
read some duck hunter blew up his kitchen.

If someone knows of a source I'm interested. I'd prefer to not have
to buy a whole pallet load, but if that is what it takes to get it
here.............................
========================
Leon McAtee


Perhaps I'm missing something, but why not just CNC machine an existing foam
block?
I realize CNC time is expensive, but I would expect the tool speed to be
much, much higher cutting foam than cutting billet aluminum, and the cost of
the discarded material would be less.

As I understand it (and it's a fairly tenuous understanding), the idea of
the lost foam is that you pack the sand around the foam, and when the molten
aluminum pours in, the foam goes away because of the heat, leaving the sand
form in place, but maintaining the sand's geometry until the metal get
there.

I understand the car manufacturers do it as a two-step process, making a
mold for the foam pieces, then using the molded foam to make the part.

But for low quantity production, carving the foam from CAD files seems like
it might be practical.

Tim Ward

[[email protected]]

On Jan 20, 9:10*pm, "Tim Ward" > wrote:

> Perhaps I'm missing something, but why not just CNC machine an existing foam
> block?

If you have ever tried to mill 2 pound foam you would understand :-)
It tends to tear and the "chips" cling to everything with static
electricity.

> I realize CNC time is expensive, but I would expect the tool speed to be
> much, much higher cutting foam than cutting billet aluminum, and the cost of
> the discarded material would be less.

Actually for the project that is being hashed out CNC just might be
the best way to do it for the average home builder. No one would have
to have anything cast, just down load some G code from a file and have
any old CNC shop make a head............... But casting is the cheap
way for those of us that have the tools to do it. If I had a 5 axis
mill in my shop I'd already be working on the G code. Who knows,
maybe once we get a proven set of head castings someone with a
digitizer might just make the required files available as freeware???

> As I understand it (and it's a fairly tenuous understanding), the idea of
> the lost foam is that you pack the sand around the foam, and when the molten
> aluminum pours in, the foam goes away because of the heat, leaving the sand
> form in place, but maintaining the sand's geometry until the metal get
> there.

You have a pretty good grasp of the essentials. One Advantage of lost
foam is that once you make up the tooling to make the foam castings
you can make things pretty quickly - and with fantastic detail. Time
wise it can be quicker than CNC and you can do some things that just
can't be done with CNC, like water jackets in a head.
========================
Leon McAtee

[Drew Dalgleish]

On Tue, 20 Jan 2009 21:03:36 -0800 (PST), "
> wrote:

>On Jan 20, 9:10=A0pm, "Tim Ward" > wrote:
>
>> Perhaps I'm missing something, but why not just CNC machine an existing f=
>oam
>> block?
>
>If you have ever tried to mill 2 pound foam you would understand :-)
>It tends to tear and the "chips" cling to everything with static
>electricity.
>
>> I realize CNC time is expensive, but I would expect the tool speed to be
>> much, much higher cutting foam than cutting billet aluminum, and the cost=
> of
>> the discarded material would be less.
>
>Actually for the project that is being hashed out CNC just might be
>the best way to do it for the average home builder. No one would have
>to have anything cast, just down load some G code from a file and have
>any old CNC shop make a head............... But casting is the cheap
>way for those of us that have the tools to do it. If I had a 5 axis
>mill in my shop I'd already be working on the G code. Who knows,
>maybe once we get a proven set of head castings someone with a
>digitizer might just make the required files available as freeware???
>
>> As I understand it (and it's a fairly tenuous understanding), the idea of
>> the lost foam is that you pack the sand around the foam, and when the mol=
>ten
>> aluminum pours in, the foam goes away because of the heat, leaving the sa=
>nd
>> form in place, but maintaining the sand's geometry until the metal get
>> there.
>
>You have a pretty good grasp of the essentials. One Advantage of lost
>foam is that once you make up the tooling to make the foam castings
>you can make things pretty quickly - and with fantastic detail. Time
>wise it can be quicker than CNC and you can do some things that just
>can't be done with CNC, like water jackets in a head.
>=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D
>Leon McAtee

Fascinating reading. You guys have metal working skills way beyond my
experience. So maybe this is a stupid question but might it be easier
to add a water jacket to an existing head

[Maxwell[_2_]]

"Tim Ward" > wrote in message
...
>

The biggest obstacle to CNC machining is down inside the ports. While it is
done every day, it requires more tooling than most economical CNC shops
possess, and would probably add greatly to a job as small as four heads.

[[email protected]]

On Jan 21, 7:13*am, (Drew Dalgleish)
wrote:
So maybe this is a stupid question but might it be easier
> to add a water jacket to an existing head

Not a stupid question at all. In fact it has been done to the air-
cooled VW head and isn't all that hard. Far less work than making a
casting. IMHO water cooled aircraft engines have some real
advantages.

BUT..............

There are lots of individuals that prefer the simplicity and
reliability of an air-cooled noise maker.
===========================
Leon McAtee

[Anthony W]

wrote:

> Not a stupid question at all. In fact it has been done to the air-
> cooled VW head and isn't all that hard. Far less work than making a
> casting. IMHO water cooled aircraft engines have some real
> advantages.
>
> BUT..............
>
> There are lots of individuals that prefer the simplicity and
> reliability of an air-cooled noise maker.
> ===========================
> Leon McAtee

If this is that simple, perhaps it's worth doing. There is a small
electric water pump used in Mercedes-Benz heaters that could be used
with a motorcycle aluminum radiator that just might to the job... It's
worth thinking about anyway.

Many sport bike radiators can be had used cheap off eBay because they're
so well tucked in that they don't get smashed when the bikes crash. I
recently bought a Kawasaki 500 radiator for $12...

Tony

[Maxwell[_2_]]

"Anthony W" > wrote in message
...
> wrote:
>
>> Not a stupid question at all. In fact it has been done to the air-
>> cooled VW head and isn't all that hard. Far less work than making a
>> casting. IMHO water cooled aircraft engines have some real
>> advantages.
>>
>> BUT..............
>>
>> There are lots of individuals that prefer the simplicity and
>> reliability of an air-cooled noise maker.
>> ===========================
>> Leon McAtee
>
> If this is that simple, perhaps it's worth doing. There is a small
> electric water pump used in Mercedes-Benz heaters that could be used with
> a motorcycle aluminum radiator that just might to the job... It's worth
> thinking about anyway.
>
> Many sport bike radiators can be had used cheap off eBay because they're
> so well tucked in that they don't get smashed when the bikes crash. I
> recently bought a Kawasaki 500 radiator for $12...
>
> Tony

While this might be a good solution for some builders and designs, I would
test the radiator at 75% power for an hour or so before wrapping an aircraft
around it. Motorcycles seldom run at 75% power long enough to over heat. You
might need a good bit more radiator.

[[email protected]]

On Jan 20, 10:03*pm, "
> wrote:
> On Jan 20, 9:10*pm, "Tim Ward" > wrote:
>
> > Perhaps I'm missing something, but why not just CNC machine an existing foam
> > block?
>
> If you have ever tried to mill 2 pound foam you would understand :-)
> It tends to tear and the "chips" cling to everything with static
> electricity.

It looks like milling foam is not as much of a problem as I thought.
Just goes to show you that just because I/we haven't been able to do
something that it isn't possible :-)

http://www.theworkshop.ca/machining/FoamMill/Foammill16/FoamMill16.htm

Using this guys existing setup and milling foam from something like
1/4" sheets and then stacking them all together just might work!

And the thought occurred to me that one could substitute a hot point,
like a soldering iron tip, to do the "milling"
===================
Leon McAtee

[Anthony W]

Maxwell wrote:

>>> Not a stupid question at all. In fact it has been done to the air-
>>> cooled VW head and isn't all that hard. Far less work than making a
>>> casting. IMHO water cooled aircraft engines have some real
>>> advantages.

>> If this is that simple, perhaps it's worth doing. There is a small
>> electric water pump used in Mercedes-Benz heaters that could be used with
>> a motorcycle aluminum radiator that just might to the job... It's worth
>> thinking about anyway.
>>
>> Many sport bike radiators can be had used cheap off eBay because they're
>> so well tucked in that they don't get smashed when the bikes crash. I
>> recently bought a Kawasaki 500 radiator for $12...
>>
>> Tony
>
> While this might be a good solution for some builders and designs, I would
> test the radiator at 75% power for an hour or so before wrapping an aircraft
> around it. Motorcycles seldom run at 75% power long enough to over heat. You
> might need a good bit more radiator.

Actually I was thinking about using 2 of them but there are other bike
radiators that are larger. I'm more worried about welded in water
jackets cracking than not being about to get enough radiator surface area.

Tony