what every boy needs - yeah seriously

Charles Vincent wrote:
jan olieslagers wrote:
schreef:
Indeed, comparing the American & British efforts makes a damn good
adventure novel -- one in which the British should have won (ie,
because of their slide-valve engines).

[[off-topic, only of interest to historians:]]

Bob, you are writing history here as a US'an crediting a US patent to
a non-US'an! Indeed Mr. Charles Yale Knight, first holder of
sleeve-valved engine patents, was born in Indiana, USA, in 1868, at
least that's what I learn from http://en.wikipedia.org/wiki/Knight_Engine

Then again, his idea was based upon early concoctions by German Mr.
Otto, and then again his ideas were most succesfully implemented in
Europe, in some British aero-engines (Bristol Centaurus and its
predecessors) but also in the notorious luxury Minerva cars from
Belgium - that factory was close to my home, indeed the allies only
nearly missed killing my mother when trying to bomb the factory in May
1943.


KA

Yeah an American invented it, but it took Harry Ricardo and crew to make
it really sing.

Charles

From what I remember from the vintage car meets is that the
sleeve-valve Willies-Knight, is that even in good running condition
would smoke like a two stroke. It's one of those screwy inventions best
left to the history books.

Tony

"Anthony W" wrote in message
...
Charles Vincent wrote:
jan olieslagers wrote:
schreef:
Indeed, comparing the American & British efforts makes a damn good
adventure novel -- one in which the British should have won (ie,
because of their slide-valve engines).

[[off-topic, only of interest to historians:]]

Bob, you are writing history here as a US'an crediting a US patent to a
non-US'an! Indeed Mr. Charles Yale Knight, first holder of sleeve-valved
engine patents, was born in Indiana, USA, in 1868, at least that's what
I learn from http://en.wikipedia.org/wiki/Knight_Engine

Then again, his idea was based upon early concoctions by German Mr.
Otto, and then again his ideas were most succesfully implemented in
Europe, in some British aero-engines (Bristol Centaurus and its
predecessors) but also in the notorious luxury Minerva cars from
Belgium - that factory was close to my home, indeed the allies only
nearly missed killing my mother when trying to bomb the factory in May
1943.


KA

Yeah an American invented it, but it took Harry Ricardo and crew to make
it really sing.

Charles

From what I remember from the vintage car meets is that the sleeve-valve
Willies-Knight, is that even in good running condition would smoke like a
two stroke. It's one of those screwy inventions best left to the history
books.

Tony

IIRC, a lot of two stroke diesels, especially GM, used it successfully.
However, I don't know if they smoked any more than other diesels.

Peter

First off, we can forget about lost-foam or anything more exotic than
green-sand, simply because there aren't enough of us.

Lost foam isn't all that "high tech" and is actually well within the
ability of anyone that can build their own foundry and ram up some
sand. Classic lost wax is still a viable option and if one uses oil
based sand rather than bentonite green sand you can get much better
detail and steeper angles - but you do need a muller for oil sand.

Here again, borrow a page from the Corvair (or from GM) and we end up
with a 'rocker arm' that actually works. *The tricky bit is that it
does NOT need to be aligned on a shaft... we can literally put a valve
anywhere there is room. *And that means at any angle as well.

My conclusion as well - but if the angles aren't chosen very carefully
we end up with greater than stock side loads on the lifters - thus my
conclusion that we need a new cam at some point or run the risk of
accelerated lifter bore wear. Trying to put a second plug in the mix
and I'm not smart enough to come up with angles that I'm comfortable
with.

Personally I see no need for 2 plugs per cylinder. When was the last
time anyone heard of a spark plug failing with out warning? As for
flame front prorogation, the only real justification for dual plugs
other than unreliable magnetos, we just don't need them on a VW based
engine unless you start thinking high rpm's and a PSRU. But that's
getting too far away from the cheap and simple.


So we make a L-head and an R-head; mirror images. *We do the best we
can with the fins but recognize our limitations and leave the most
difficult of them as CUT fins

If we do the split heads (still need 2 cores, front and rear) the fins
can be rough cast and then finished up on a lathe. The mention of
sawing gives me the idea of using a saw mounted on the lathe for
quicker cutting than a standard tool and maybe even thinner fins. Band
saw off the fins next to the other head and your done. No CNC
needed. My next set of 1/2 VW heads will be done this
way................if I ever get around to a next set.
=======================
Leon McAtee

wrote in message
...
*
* First off, we can forget about lost-foam or anything more exotic than
* green-sand, simply because there aren't enough of us.
*
*Lost foam isn't all that "high tech" and is actually well within the
*ability of anyone that can build their own foundry and ram up some
*sand. Classic lost wax is still a viable option and if one uses oil
*based sand rather than bentonite green sand you can get much better
*detail and steeper angles - but you do need a muller for oil sand.
*
*Leon McAtee

How can you mold or sculpt invest foam articles with a simple hobby process,
and then get something as detailed as air cooled fins on a foam or wax
investment to withstand even the most careful ramming process for green
sand, oil sand or air set casting?

Also, if you use oil sand and wax investments, how can you possibly remove
enough wax from the mold to allow the introduction of molten aluminum and
yeild a useable casting, when you have detail as fine as a cooling fin?

On Jan 10, 9:27*am, "Maxwell" #$$9#@%%%.^^^ wrote:

How can you mold or sculpt invest foam articles with a simple hobby process,
and then get something as detailed as air cooled fins on a foam or wax
investment to withstand even the most careful ramming process for green
sand, oil sand or air set casting?
------------------------------------------------------------------------------------------

Dear Maxwell,

While there are some pretty sturdy plastic-like waxes that can
withstand ramming-up in a core box, most of the methods using lost wax
begin by DIPPING the wax model in a slurry of high-temperature CLAY,
after all of the sprues, vents gates and supports have been attached
manually. After the clay dries it is BAKED, first at a fairly low
temperature ( ie 200F ), during which it is rotated several times to
get rid of the casting wax, and finally at a higher temperatures, such
as 500F for about two hours. The resulting product is then stiff
enough to withstand ramming.

There are variations to this theme. Some call for several dipping &
baking episodes using different recipes of clay. Dentists are the
best source of information on this procedure. The main down-side is
the HIGH COST of the refractory clay dips.

-Bob

wrote in message
...
On Jan 10, 9:27 am, "Maxwell" #$$9#@%%%.^^^ wrote:

How can you mold or sculpt invest foam articles with a simple hobby
process,
and then get something as detailed as air cooled fins on a foam or wax
investment to withstand even the most careful ramming process for green
sand, oil sand or air set casting?
------------------------------------------------------------------------------------------

Dear Maxwell,

While there are some pretty sturdy plastic-like waxes that can
withstand ramming-up in a core box, most of the methods using lost wax
begin by DIPPING the wax model in a slurry of high-temperature CLAY,
after all of the sprues, vents gates and supports have been attached
manually. After the clay dries it is BAKED, first at a fairly low
temperature ( ie 200F ), during which it is rotated several times to
get rid of the casting wax, and finally at a higher temperatures, such
as 500F for about two hours. The resulting product is then stiff
enough to withstand ramming.

There are variations to this theme. Some call for several dipping &
baking episodes using different recipes of clay. Dentists are the
best source of information on this procedure. The main down-side is
the HIGH COST of the refractory clay dips.

-Bob

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

I'm well aware of the variations in the investment casting process, but you
hand already limited the discussion to a sand casting, and for economic
reasons I would have to agree. But there is no way to use a wax investment
in a sand casting. Subsequent melting of the wax will contaminate the sand
mold, regardless of green sand, oil sand or air set.

Considering the use of foam, first we have to mold or sculpt a foam cylinder
head in full detail for each head we have to produce. Then adequately pack
sand between the fins of a foam pattern, when the fins are as detailed as
this project would require. Doesn't sound possible, much less practical to
me.

On Jan 10, 10:27*am, "Maxwell" #$$9#@%%%.^^^ wrote:
wrote in message


How can you mold or sculpt invest foam articles with a simple hobby process,
and then get something as detailed as air cooled fins on a foam or wax
investment to withstand even the most careful ramming process for green
sand, oil sand or air set casting?

Your're thinking WAY too much inside the box. Making the molds for
the wax/foam cores is simple and there are many references to the
process(s) on the internet.

Ramming up sand directly on a foam or wax mold - isn't - practical.
Maybe if you resorted to vibration to pack core sand and then gas the
whole thing with CO2 ? But there is a way around that limitation as
well. Again, a search on the net should turn up some clues. I'd find
a link or 2 for you to start but I have to head out for the weekend
shopping with the Wife .............. maybe this evening.


Also, if you use oil sand and wax investments, how can you possibly remove
enough wax from the mold to allow the introduction of molten aluminum and
yield a usable casting, when you have detail as fine as a cooling fin?

I may have been unclear in my earlier post. I did not intend to imply
using oil based sands with investment casting. Sounds kind of messy!
I meant that oil based sand allows one to make better detail and
thinner parts than you can get with bentonite based sands. Should
have been a separate paragraph...............

Investment casting of the quality needed is very doable by the hobby
caster.
=====================
Leon McAtee

wrote in message
...
On Jan 10, 10:27 am, "Maxwell" #$$9#@%%%.^^^ wrote:
wrote in message


How can you mold or sculpt invest foam articles with a simple hobby
process,
and then get something as detailed as air cooled fins on a foam or wax
investment to withstand even the most careful ramming process for green
sand, oil sand or air set casting?

Your're thinking WAY too much inside the box. Making the molds for
the wax/foam cores is simple and there are many references to the
process(s) on the internet.
-------------------------------------------------------

Care to provid a link of something as complex as VW head, "hobby" molded in
foam?





Ramming up sand directly on a foam or wax mold - isn't - practical.
Maybe if you resorted to vibration to pack core sand and then gas the
whole thing with CO2 ? But there is a way around that limitation as
well. Again, a search on the net should turn up some clues. I'd find
a link or 2 for you to start but I have to head out for the weekend
shopping with the Wife .............. maybe this evening.
-------------------------------------------------------------

Doesn't matter what other process there are, you still have to have the
"hobby" molded foam or wax investment.




Also, if you use oil sand and wax investments, how can you possibly remove
enough wax from the mold to allow the introduction of molten aluminum and
yield a usable casting, when you have detail as fine as a cooling fin?

I may have been unclear in my earlier post. I did not intend to imply
using oil based sands with investment casting. Sounds kind of messy!
I meant that oil based sand allows one to make better detail and
thinner parts than you can get with bentonite based sands. Should
have been a separate paragraph...............

Investment casting of the quality needed is very doable by the hobby
caster.
---------------------------------------------------------------

If you can reference any hobby process that will made it "simple" to cast
custom air cooled VW heads at home. I can assure you, I'm not the only
person on this group that would like to see a link.

On Jan 10, 1:44*pm, "Maxwell" #$$9#@%%%.^^^ wrote:
wrote in message

If you can reference any hobby process that will made it "simple" to cast
custom air cooled VW heads at home. I can assure you, I'm not the only
person on this group that would like to see a link.

I'd never have thought this technology was that obscure :-) 'course
it depends on your definition of "simple". You have to make or buy a
whole bunch of new tools and learn a few new skills if you have never
done it before. Kind of like making an airplane from a pile of raw
materials (the token aviation reference)

To me it's pretty straight forward use of patterns and molds, but then
again I had the good fortune of my grandfather showing me how to make
molds and fire porcelain things just shy of 50 years ago. We could
have made VW head molds back then using nothing more sophisticated
than some clay, plaster and green soap. The materials available
today make the process MUCH easier.

Fire up Google and see what others are doing.

My first exposure to hobby foam casting came from such an adventure
and was found of all places on a site run by a den mother describing
how to make foam trinkets for the kids to paint. If some 8 year old
kids can do it.......................

http://www.foundry101.com/racert2.htm

Not the site I had in mind but this is using green sand - with enough
detail and complexity for a VW head.

I've also been keeping my eye on a couple of interesting projects
being pursued by "Why Not!" types trying to build inexpensive 3D
printers. Think what we could cast up with one of those out in the
garage.
=========================
Leon McAtee

On Jan 10, 1:44*pm, "Maxwell" #$$9#@%%%.^^^ wrote:
wrote in message

If you can reference any hobby process that will made it "simple" to cast
custom air cooled VW heads at home. I can assure you, I'm not the only
person on this group that would like to see a link.

Couldn't find the site I discovered a few years ago - even had some
pictures - but I did find these this afternoon after a quick google.

http://www.plansandprojects.com/My%2...am_casting.htm
https://duckdeco.dkgnet.com/Molds.htm
http://www.tempo-foam.com/engineerin...ands_index.htm
http://www.wowessays.com/dbase/af2/skx196.shtml
http://www.mate.tue.nl/mate/showabstract.php/3871
http://www.answers.com/topic/expande...yrene-foam-epf

Combine this info with the fact that we can buy silicone casting
compound that lets us directly cast low melt metals like zinc and
pewter and I'll leave it up to the reader to connect the dots.

My only problem now is finding a source of the EPS beads again. One
of the local hobby-n-craft stores had them, but they went the way of
the missing web site.
=====================
Leon McAtee