More New Heads

To All:

Having received an up-check from my latest visit to the Doctor Shop, I
went for a hike today. I hiked all the way from the shop to the
office, then from the office to the shed and then back again, this
time carrying a pair of defunct Volkswagen heads, selected from a pile
of such heads that has been allowed to accumulate in said shed.

This particular pair of heads is going into the smelter, to become
bright, shiny ingots of VW Head Alloy, whatever that happens to be.
Later on in this story, the ingots will be re-melted and cast into
FINS, and into Exhaust Ports.

Why? Well, follow me through on this because it gets sorta wacky.

In the Saga of the Fat Finned Heads I mentioned that the best stuff,
with regard to welding new fins onto existing heads, proved to be
stock fins, cut from damaged heads. The only flaw with this method
( that is, increasing the fin-area of existing heads by TIG'ging on
additional fin-area ) was the horrible lack of experience on the part
of the weldor, which was me. So what if my skills have improved
slightly during the passed forty-odd years? Ah ha! (you sez) Ah
ha! indeed.

So I'm going to try it again. But with a slight variation. I'm going
to first CAST fins of the required shape, giving them a nice little
Christmas Tree base like a turbine-blade, so I'll have a fin with a
more suitable SHAPE at the point of attachment. (Actually, it's not
an exact copy of a turbine-blade, but I think I'll keep the exact
shape under my hat for the moment.)

And there's another little trick or two, too. As in, also.

See that exhaust stack? On the VW heads the stacks are on the ENDS.
This makes it impossible to use that area for fins, as was done with
the Porsche engines. So there I am with a crucible of molten head-
stuff in my massively-gloved hands, casting flasks littering the area
in back of the shop...

There's at least two ways to MOVE the exhaust stacks on VW heads. I
am going to try grinding away the existing exhaust stack. I'm then
going to try CASTING a new exhaust stack. But not the whole think,
only the ROOF of the exhaust stack. I'm then going to WELD the newly
cast room onto the head in such a manner as to leave virtually the
entire area at the ends of the VW heads available for NEW FINS.

This method is far from being a slam-dunk. The method involves a lot
of tricky little procedures. But none of them are especially
DIFFICULT. While it involves some casting, the pieces to be cast are
all 'single-sided;' there are no cores to worry about. That means
virtually ANY METHOD of casting should yield acceptable results.

The main road-block is the need to be able to TIG weld. TIG is not
difficult to learn, the 'road-block' is fiscal -- even the cheapest
TIG'er is going to set you back about $1500. Which means you've got
to start going to Chapter meetings again, standing up and waving your
needs in the air.

-R.S.Hoover

PS -- I'll post some drawings on my blog so you can get some idea as
to what I'm talking about.

Okay, okay... belay '..grinding..' with my reference to aluminum; I
meant cutting, as with a 3" dia. circular saw-blade driven by a die-
grinder, and using a suitable tool to smooth the resulting surface,
which will become the inner-lower part of the exhaust duct. This is
WELDED so as to present a SOLID SURFACE to the exhaust gases. This
surface is shaped with appropriate tools so as to form a channel that
in all respects equal to the inside of the exhaust stack.

Then you weld a roof over the channel. But not all at one time The
diameter of the resulting tube, duct or whatever you want to call it
-- the pipe that is down-stream from the exhaust valves -- limits the
size of the tools you can use, forcing you to weld-on the 'roof' no
more than about an inch at a time. You are welding from the outside.
WHAT you are welding are pieces of the 'roof' that have been CAST to
the required shape & thickness. Once welded in place, you go at the
INNER SURFACE with your die-grinder and what-not, removing any
evidence of welding.

Then you do it again; welding on ANOTHER section of the exhaust
stack's 'roof.'

The goal here is to create a NEW exhaust stack, moving its OUTLET to
the lower side of the cylinder head. The final weldment is the FLANGE
for the exhaust pipe, which has now been moved so that it points
DOWN. The inner surface of this section is perfectly smooth since you
have dressed the welds as the work progressed.

NOW you go back and attach FINS to the outer surface of the exhaust
stack, whilst adding approximately 1.5" of fin to the four outer-most
fins on the stock cylinder head. You have only THREE new fins and
they are spaced slightly WIDER APART than the four outer-most fins.

The net effect is to move the exhaust stack outlets AND to increase
the surface-area of the existing fins.

The ADVANTAGE of doing it in this fashion is that it is a procedure
that virtually ANYONE can do. You need some junk heads as your source
of metal but since a stock head weighs about eleven pounds, there is
plenty of material out there -- it just needs to be discovered and
melted-down.

Since the largest pieces to be cast are the FINS, you can get by with
small flasks, a small crucible and a small furnace, which can be
fueled with charcoal if you've nothing better at hand. The PATTERNS
can be of wood. Since you have the head right in front of you, you
need only carve the pattern to fit. To allow easy handling of the
patterns (it will take about a dozen of them) you can put a flange on
one end.

Yeah, it's a cock-eyed method. But the probability of SUCCESS
approaches 100%. And yes, it is labor-intensive -- you need to make
about a dozen little molds for the 'roof.' You can do the 'floor' by
building up strips of cast metal, welding them to the underlying head
at all points until you have a SOLID base for the exhaust stack.

The resulting product of this procedure is a cylinder head having more
than twice the fin area of a stock head, and one in which the exhaust
ports are facing downward. I've already had one fellow ask about the
PRICE of such a head. I'll let someone else answer that question.
The first one of course, will probably be too expensive for most
people but once you've made the patterns the amount of labor will
fall, bringing the price down to something most people can afford.
And of course, the procedure CAN be followed by literally ANYONE,
assuming they have the necessary casting equipment & experience.
Personally, I don't plan to build such heads for SALE but it would
appear that a lot of people are heading that direction.

-R. S. Hoover

On Jan 23, 9:37*am, " wrote:

Then you weld a roof over the channel.
-R. S. Hoover

If all you want to do is move the port down to give more room for fins
why not just bore a 35/37mm hole straight to the valve and sleeve with
a steel tube insert - similar to the "tube port" intake modification
one of the VW tuners developed years ago?

The steel tube keeps the exhaust heat in and you might even be able to
use the steel to puddle your welding upon.
===============================
Leon McAtee

Clay and valves in hand.....................

On Jan 23, 9:29*am, "
wrote:

If all you want to do is move the port down to give more room for fins
why not just bore a 35/37mm hole straight to the valve and sleeve with
a steel tube insert - similar to the "tube port" intake modification
one of the VW tuners developed years ago?
-----------------------------------------------------------------------------------------------

1. I'm building an aircraft engine, not a dragster.

2. I don't know how to weld cast aluminum to mild steel. (yean,
okay...3-axis xray welding in a vacuum tank... but I don't have any of
that stuff.
----------------------------------------------------------------------------------------------

Welding cast aluminum to cast aluminum, okay. And doing it just 3/4"
at a time, okay (because that leaves room to get my tools onto the new
weld and smooth it out). Then I get to weld FINS all over the place:
cast al. to cast al., which SHOULD allow me to increase the maximum
SUSTAINABLE output to about 50bhp or thereabouts.

In theory then, nothing stands in the way of producing a pair of Fat
Fin Heads (Modified), having their exhaust ports on the underside of
the engine WITHOUT turning the thing into a mare's nest of exhaust-
pipe plumbing. With one exception: At the moment, I'm unable to LIFT
my home-made foundry.

Since being diagnosed with cancer I have lost a considerable amount of
weight, not all of which was fat. Hauling a pair of VW heads (about
11 lbs each) from a storage shed up to the house left me unable to
mount the two steps when I got there. I had to put the heads down on
the top step then hoist MYSELF first to the one, then to the other,
and from there into a chair in the kitchen.

I know what you're thinking: Being unable to lift a total of 22
pounds sounds like the punch line of a bad joke but there it is. Even
worse is the fact I can not presently move my 'foundry' (a steel drum
lined with refractory material and fitted with a vented lid of the
same stuff. In use, chunks of aluminum are stuffed into a home-made
crucible that is placed atop a bed of charcoal in the heart of the
furnace. More charcoal is stacked around the sides of the crucible
and the whole thing set afire. Draft is provided by a 2" dia pipe. I
can plug the business-end of a propane burner into the 2" pipe and
have everything glowing cherry red in a matter of minutes. Or I can
depend entirely on the charcoal to do the same, albeit in a longer
period of time. Once the contents of the crucible are melted, the lid
is removed and the crucible lifted out using tongs of a suitable
design. If the flasks are near at hand,, as they are supposed to be,
tipping the contents of the crucible down the filler of the flask,
with lots of hissing & steam.

The only problem with all of that is that I can't LIFT the damn
thing! Seriously! Twenty pounds feels like a hundred and the Doc has
warned me I'm liable to give myself another compression fracture.

So what's the cure? Time. And exercise (!!)

Their version of 'exercise' is a pair of 5 pound cast-iron bar-bells,
pumped overhead for 25 reps... once a day. So I do that. And they
gauge my progress by the strength of my grip. Indeed, I am now
allowed to do the exercise TWICE a day.

As silly as it sounds, despite the small amount of stress (ie, #5),
the exercise appears to be working... I've noticed I can get a gallon
of milk from the refrigerator with much less effort. But hauling a
pair of VW heads up from the shed felt like climbing Mt. Whitney.(*)
I can't imagine what it would feel like to try moving the furnace.

I'll post a picture of it on the blog.

-Bob

(*) -- Despite being a 'Fourteener" (ie, over 14,000' elevation
[indeed, it's the highest peak in the lower 48] ) Mt. Whitney is a
'walk-up.' No real 'mountain climbing' required. Climbing it is an
interesting way to spend a week-end.

On Jan 24, 12:48*pm, " wrote:
On Jan 23, 9:29*am, "

1. *I'm building an aircraft engine, not a dragster.

The "vair has a similar tube port. Some even FLY behind them :-)

2. *I don't know how to weld cast aluminum to mild steel.


Neither do I know how to weld aluminum to steel, but I have used a
steel or copper plate to flow melted aluminum from a MIG onto as sort
of a "cast as you go" way of building up aluminum for further
welding. It might work with a TIG as well?

As for the weakness, with a constitution such as yours I'm sure it
will return ............... or you will find an ingenious away around
the problem.
========================
Leon McAtee

On Jan 24, 9:05*pm, "
wrote:

Neither do I know how to weld aluminum to steel, but I have used a
steel or copper plate to flow melted aluminum from a MIG onto as sort
of a "cast as you go" way of building up aluminum for further
welding. *It might work with a TIG as well?
--------------------------------------------------------------------------

Yes, it does. But I don't know how I could maintain the required
clearance as the 'tunnel' advanced.

There's a strong possibility we are looking at the job from entirely
different points of view. My lack of skill with TIG reflects my lack
of experience. 'Coppering' is fairly common with TIG for automotive
sheet metal repairs but I've never seen a copper with that amount of
curvature. It will take virtually a solid bar to handle the amount of
heat needed with aluminum.

This will sound a little crazy but in my head I've linked the Chugger
project with the cancer, in that success with one means success with
the other.

On Jan 24, 9:05*pm, "
wrote:
On Jan 24, 12:48*pm, " wrote:

The "vair has a similar tube port. *Some even FLY behind them :-)
------------------------------------------------------------------------

The Corvair exhaust port already points straight down. Plenty of room
on the ends of the heads for fins. On the VW the exhaust port is
horizontal off the end of the head. Converting to a tube-type port
would provide no benefit with regard to added fins. Indeed, the
existing port may be defined as a tube-type, plus having the advantage
(over the Corvair) of two bolts vs one.

While comments are always welcome it helps if both parties have some
experience with the engine(s) in question... Or at least looked at
them. Or whatever. A recent post took me to task for "wasting time"
on the early VW engines when the later model was such an obvious
improvement... failing to take into account the economic factors
involved when dealing with an engine, the parts for which remain in
production. For those who might be interested, converting a Type IV
for flight typically costs about the same (or even more) as
overhauling an A65-O200, since the Porsche-types are willing to pay a
premium for the T4... and do not have the option of installing a
Continental.

-R.S.Hoover