Rocket Man VW Heads... What alloy?

Okay, then YOU name the damn things!

Right now I got a couple questions: VW heads are nearly pure
aluminum. I've got a pile of the things but odds are, every single
one of them is worth a $25 bill... or will be. Point is, I don't much
care for the idea of cutting them and melting them down.

When I make something SERIOUS out of aluminum I usually use old
pistons, which is a pretty hard alloy with a MUCH lower heat-transfer
ability than VW heads.

So what's a good alloy? Ideally, something cheap & commonly available
(and doesn't say 'Coors'!)

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

Second question: Rocket Man heads needum' rockers. I wuz thinking of
using Chebby 1.3 break-in rockers. Any better ideas? (Or rather,
any ideas at all?)

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

-Bob

On Fri, 9 Jan 2009 19:34:01 -0800 (PST), "
wrote:

Okay, then YOU name the damn things!

Right now I got a couple questions: VW heads are nearly pure
aluminum. I've got a pile of the things but odds are, every single
one of them is worth a $25 bill... or will be. Point is, I don't much
care for the idea of cutting them and melting them down.

When I make something SERIOUS out of aluminum I usually use old
pistons, which is a pretty hard alloy with a MUCH lower heat-transfer
ability than VW heads.

So what's a good alloy? Ideally, something cheap & commonly available
(and doesn't say 'Coors'!)

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

Second question: Rocket Man heads needum' rockers. I wuz thinking of
using Chebby 1.3 break-in rockers. Any better ideas? (Or rather,
any ideas at all?)

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

-Bob

70 years ago there was an english inline 4 which has some surprisingly
state of the art aspects to the design.
it was called the gypsy major.
heads were cast out of "Y" metal. which is an aloominum alloy with
some exotic stuff in it.
those engines put out 140hp.

the use of auto engine rockers from an engine that could turn 9,000rpm
seems to have a lot going for it.
the use of auto pistons and rings has a lot going for it as well.
....and con rods.

incorporation of auto engine parts is a successfully trod path.
the jabiru engines have a number of similar included components.

Stealth Pilot

wrote in message
...
| Okay, then YOU name the damn things!
|
| Right now I got a couple questions: VW heads are nearly pure
| aluminum. I've got a pile of the things but odds are, every single
| one of them is worth a $25 bill... or will be. Point is, I don't much
| care for the idea of cutting them and melting them down.
|
| When I make something SERIOUS out of aluminum I usually use old
| pistons, which is a pretty hard alloy with a MUCH lower heat-transfer
| ability than VW heads.
|
| So what's a good alloy? Ideally, something cheap & commonly available
| (and doesn't say 'Coors'!)
|
| -------------------------------------------------------------------------------------------------------

The after market racing heads are usually made from 355 or 356, and heat
treated to T-6. Regardless of it's previous use, I wouldn't recommend
reclaiming anything. Every time you melt aluminum you gain and loose
elements, and usually reduce or at least changes it's physical properties.
It's too cheap and easy to just use an off the shelf alloy with known
physicals.

|
| Second question: Rocket Man heads needum' rockers. I wuz thinking of
| using Chebby 1.3 break-in rockers. Any better ideas? (Or rather,
| any ideas at all?)
|
| -------------------------------------------------------------------------------------------------------
|

Are you talking about 1.3 Chevy?

70 years ago there was an english inline 4 which has some surprisingly
state of the art aspects to the design.
it was called the gypsy major.
heads were cast out of "Y" metal. which is an aloominum alloy with
some exotic stuff in it.
those engines put out 140hp.
----------------------------------------------------------------------------------------------------------------

I've played with a few of them. Mechanics called it the Australian
Gypsy (because it ran upside down). With turbosupercharging and a few
other tricks, the Major labored on well into the 1950's (as a
helicopter powerplant). But I don't recall any exotic claims about
it's aluminum head. I know you could run the early models on tractor
gas. (Damn! I can't remember the name of the little bipe that first
used the Gypsy. The wings folded back.) Anyway, the CR was about
5:1; something like that.

After WWII my dad worked on several 'Miles' aircraft that had found
their way to southern California. He got the job mostly because they
were made of plywood, but also because they used the de Havilland
engine.

One reason the engine was dry-sumped (according to my dad) was because
the thing DRANK oil. Inside the cowling it was a real swamp, unlike
the Walther, which was tidy by comparison.

As a point of interest, you should be able to air-cool virtually ANY
in-line four by sawing off the cylinders, machining what remains, then
replacing the jugs with something having fins. The tricky bit would
be casting an aluminum head. (Why does that sound familiar?) We
tried doing that with the Vega engine, which was supposed to power a
whole line of 'air-show replicas' (about 1973)

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

the use of auto engine rockers from an engine that could turn 9,000rpm
seems to have a lot going for it.
the use of auto pistons and rings has a lot going for it as well.
...and con rods.
---------------------------------------------------------------------------------------------------------------------------------------------

Prolly not as much as you think. It's the PROPELLER that dictates the
'life-style' of an aircraft engine. The fact you've used rockers from
an engine that turns six grand doesn't mean a lot. Stock VW valve-
train components are good to above 5-grand... if you don't go crazy
with the valve-spring tension. But anything faster, you're going to
need push-rods like telephone poles... and valve springs that would be
right at home in a landing gear.
--------------------------------------------------------------------------------------------------------------------------------------------

incorporation of auto engine parts is a successfully trod path.
the jabiru engines have a number of similar included components.

-------------------------------------------------------------------------------------------------------------------------------------------
Sure. Any time you can utilize an off-the-shelf, mass-produced
component you'll be money ahead. The expensive bits are billet cranks
and custom cams.

Nowadays we've got filled-epoxy compounds that do as well as castings
for such things as sumps, rocker covers and so on.

-Bob

Stealth Pilot

On Jan 10, 9:18*am, "Maxwell" #$$9#@%%%.^^^ wrote:
|
| So what's a good alloy? *Ideally, something cheap & commonly available
| (and doesn't say 'Coors'!)
|
| -------------------------------------------------------------------------------------------------------

The after market racing heads are usually made from 355 or 356, and heat
treated to T-6.
---------------------------------------------------------------------------------

Are you talking air-cooled heads?

356-T6 is usually selected for its HIGH STRENGTH rather than its
ability to pass heat
--------------------------------------------------------------------------------

Regardless of it's previous use, I wouldn't recommend
reclaiming anything. Every time you melt aluminum you gain and loose
elements, and usually reduce or at least changes it's physical properties..
It's too cheap and easy to just use an off the shelf alloy with known
physicals.
------------------------------------------------------------------------------

I'm afraid you've confused me with some of those Double-Dipper Retired
Military types :-) Whatever I use for casting will have to come from
the junk yard.

I can get two engines-worth of 1.3:1 rockers for $200, which is about
the only thing I'd care to buy. I'll hit the junk yards over by the
airport to see if I can come up with the studs & hardware.

My casting ability is limited to about one quart of melted aluminum,
which should be enough for the type of heads I'm thinking about.

This puppy is going to need two cores. Pulling an accurate core is
where I've had trouble in the past. That is, using the Old Fashioned
method of baking cores. (Smells like a batch of cookies... until the
cores reach the carbonizing stage. In the past, I've scheduled Core
Production for those times when I'm home alone... then try to air-out
the kitchen before my wife returns :-)

It's unfortunate that, with almost a thousand 'subscribers,' grass-
roots ideas such as this, the primary glider and so forth, garner so
little attention. On the other hand, I continue to suffer what the
physicians refer to as 'mini-strokes' that leave me wanting when I try
to recall something like a pass-word or telephone number... with the
'chuggers' Group being a good case-in-point. I've no idea in the blue-
eyed world what 'chuggers' expects for my screen-name or password.
(Kinda reminds me of the two geezers who went for a local hop in the
one's freshly licensed home-built, which began with a neat diving turn
to pass UNDER a local powerline. But he finally climbed up to a sane
altitude and except for sneaking in a bit of input now & then, the
flight was a lot of fun. Unfortunately, as they began lining up for a
landing the pilot made no reduction in power until his friend shouted,
"Keee Rist! Jim! Are you trying to get us killed?" To which Jim gave
his friend a guilty look. "Actually, I thought YOU were flying
today.")

Still flying today.
-Bob

wrote in message
...
On Jan 10, 9:18 am, "Maxwell" #$$9#@%%%.^^^ wrote:
|
| So what's a good alloy? Ideally, something cheap & commonly available
| (and doesn't say 'Coors'!)
|
| -------------------------------------------------------------------------------------------------------

The after market racing heads are usually made from 355 or 356, and heat
treated to T-6.
---------------------------------------------------------------------------------

Are you talking air-cooled heads?

356-T6 is usually selected for its HIGH STRENGTH rather than its
ability to pass heat
--------------------------------------------------------------------------------

Which sand cast alloys do you thing will conduct heat significantly faster?







Regardless of it's previous use, I wouldn't recommend
reclaiming anything. Every time you melt aluminum you gain and loose
elements, and usually reduce or at least changes it's physical properties.
It's too cheap and easy to just use an off the shelf alloy with known
physicals.
------------------------------------------------------------------------------

I'm afraid you've confused me with some of those Double-Dipper Retired
Military types :-) Whatever I use for casting will have to come from
the junk yard.
--------------------------------------------------------------------------------

Why, you can buy certifed spec metal for $1.50 to $2.00 a pound.







I can get two engines-worth of 1.3:1 rockers for $200, which is about
the only thing I'd care to buy. I'll hit the junk yards over by the
airport to see if I can come up with the studs & hardware.
--------------------------------------------------------------------------------
Are you talking about Chevy rockers?




My casting ability is limited to about one quart of melted aluminum,
which should be enough for the type of heads I'm thinking about.

This puppy is going to need two cores. Pulling an accurate core is
where I've had trouble in the past. That is, using the Old Fashioned
method of baking cores. (Smells like a batch of cookies... until the
cores reach the carbonizing stage. In the past, I've scheduled Core
Production for those times when I'm home alone... then try to air-out
the kitchen before my wife returns :-)
--------------------------------------------------------------------------
What do you use for sand and binder? How do you mix?

On 10 Jan, 18:32, " wrote:
70 years ago there was an english inline 4 which has some

other tricks, the Major labored on well into the 1950's (as a
helicopter powerplant). *But I don't recall any exotic claims about
it's aluminum head. *I know you could run the early models on tractor
gas. *(Damn! *I can't remember the name of the little bipe that first
used the Gypsy. *The wings folded back.) *Anyway, the CR was about

Tiger moth used the Gypsy Major - no idea if it was the first.

I did about 15 hours (dual except for one solo) in
a Chipmunk in the early '70s behind a Gypsy Major
and only had one failure

One mag drive gear stripped leaving the mag going
round a bit, lots of popping and banging.
Oh, at 500ft on the way up.

Kept going enough to maintain level flight but it
was disapointing that we were not high enough to
jump out.

Try that without dual ignition! Would have
been in a load of **** in this case since the
shipyards and the river (fixed gear taildragger,
not recommended for ditching) were not inviting.
Don't suppose they would have been more inviting
under a parachute

On Jan 9, 8:34*pm, " wrote:
Okay, then YOU name the damn things!

Right now I got a couple questions: *VW heads are nearly pure
aluminum. *I've got a pile of the things but odds are, every single
one of them is worth a $25 bill... or will be. *Point is, I don't much
care for the idea of cutting them and melting them down.

VW head cores are worth that much!? I've melted away a fortune :-(

When I make something SERIOUS out of aluminum I usually use old
pistons, which is a pretty hard alloy with a MUCH lower heat-transfer
ability than VW heads.


So what's a good alloy? Ideally, something cheap & commonly available
(and doesn't say 'Coors'!)


IMHO anything that would fill the mold and not shrink too much would
be usable.
Late model automatic transmission cases work for me. Pours like water
and machines clean.


If I were doing it for sale or use by another I'd probably spend the
money on fresh ingots.

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

Second question: *Rocket Man heads needum' rockers. *I wuz thinking of
using Chebby *1.3 break-in rockers. *Any better ideas? *(Or rather,
any ideas at all?)

Chevy would be my choice as well, but given that they may not make the
year maybe we should be looking at Ford parts :-)
There will be a demand for after market small block Chevy parts until
we run out of oil so that is where we vultures should be looking.

However I've been trying to remember since this thread popped up where
I ran across some nice rockers that had built in hydraulic lifters not
much bigger than the adjusting screws in a TP IV..
=======================
Leon McAtee

On Sat, 10 Jan 2009 14:11:47 -0600, "Maxwell" #$$9#@%%%.^^^ wrote:



--------------------------------------------------------------------------
What do you use for sand and binder? How do you mix?


you can make your own greensand.

basically you get some buckets of sand. plonk a gently running hose
into the bucket and let it float off everything but the sand.
keep the hose running until the water coming off is clear. this gets
rid of crap and non bentonite clays.

find or buy some bentonite clay.
you can buy sodium modified bentonite in 25lb bags.
you need bentonite clay because of its peculiar charactersitics. it is
different from all the other clays and the difference is what makes it
useful in casting.

ok let your washed sand dry off a bit.
weigh the sand and mix in 5% thereabouts by weight of bentonite.
this is the important bit; you need to put a coating of bentonite
around each sand particle. you dig your clean hands into the sand and
bentonite and with a handfull between your hands you run them back and
forth to work a coating of clay around each sand particle.
(your hands end up really smooth from this)

ok now you let your mix dry right out. this can take a week.

when you want to use the greensand you mix in 5% of water by weight
and nead the greensand so that it is uniformly wet out.

if you pat up a sausage out of it about 2" dia and a foot long you
should be able to hold this by an end and wave it all over the place
and none of the sand will part company.

you then need to do some test pours to see if the porosity of your
greensand means it is too coarse.

if you can handle that intelligently I'll go on to tell you why most
people get their furnaces wrong and what you need to do to get it
right.
Stealth Pilot

On Fri, 9 Jan 2009 19:34:01 -0800 (PST), "
wrote:

Okay, then YOU name the damn things!

Right now I got a couple questions: VW heads are nearly pure
aluminum. I've got a pile of the things but odds are, every single
one of them is worth a $25 bill... or will be. Point is, I don't much
care for the idea of cutting them and melting them down.

When I make something SERIOUS out of aluminum I usually use old
pistons, which is a pretty hard alloy with a MUCH lower heat-transfer
ability than VW heads.

So what's a good alloy? Ideally, something cheap & commonly available
(and doesn't say 'Coors'!)


-Bob

according to some evening research there are two aloominum alloys used
in automotive(water cooled) heads. AA319 which has Aluminium plus 6%
Si and 3. 5% Cu and AA 380 Aluminium plus8.5% Si and3% Cu

another source shows an old piston alloy 242 as a popular aircooled
head alloy.

lyc and cont use a 2 series alloy.

one reference mentions 220.0 -T61 as the original widely used
aircooled head alloy though now supplanted by 242.0 and 243.0 which
supposedly have better elevated temperature heat strength.

242 alloy is Aluminium with Mg 3.0%, Si 0.5%, Fe 0.5%, Mn 0.2%, Zn
0.1%, Cu 0.05% (percentages by weight)

so as a wild guess your silicon containing piston alloy mixed with
some 2024 or 6061 might just be entirely satisfactory. experimentation
will tell.

Stealth Pilot