New high production casting equipment

Hi, I’m a mexican jeweller . I live in Guadalajara,Jalisco,Mexico

-I’m considering to buy a new " Neutec,Memco or Galloni" casting
equipment, IB4m actually using “vacuum 7cfm casting”, but I have some
troubles with the melting oxidation.

Any one have experience with Neutec,Memco,Galloni machines? Does any
one knows about other option…about…$14000…or
lessssss…

-One more question…about…hi production wax injector I need a
new one! Rio grande vacuum injector with autoclamp…or…Galloni
system with autoclamp, or intellijector with autoclamp?? other option?

My english is the worst!!!

Any help appreciated

Alberto
@pareja44

Just one word of advice that I cannot express strongly enough. Stay
away from the Memco machines. Service is terrible, you cannot get
parts especially where you are and the company in my opinion only
cares about the initial sale and when it comes to follow up service
they do not care. They have left me hanging in the wind so many
times. I took my unit to a compactor and crushed it into a 1.5 square
foot lump and mailed it back to them with a receipt showing the
purchase of my new Galloni machine. Thomas

Hi we are a New Mexican casting co. We have a Memco for sale used from
1996 with tons of extras. It’s an electro Vac. with less than 1000
heats if you are interested. It works great, but we are at 2200 meter
altitude an it is to difficult to Vacuum cast with it up here. You can
only pull 21" of vacuum. Tambein hablo pocos Espanol.

Quest Jewelry Inc.
1310 Siler Rd #2
Santa Fe Nm 87505
505-473-4456
fax 505-474-7021

Dear Dominion,

You have been using a MEMCO ElectroVac. This means, you are using
non-graphite, ceramic crucibles; and using Forming Gas (a kinda-sorta
substitute for cracked ammonia, the preferred atmosphere for
production jewelers). This means you are by now used to troublefree,
micro-porosity-free (or as near to that as dammit!) castings, which
you are NOT going to get out of equipment using graphite crucibles
with or without Argon, Nitrogen or whatever.

You are about to let go of these tremendous advantages, because at
your geographical elevation you are not getting “enough vacuum”.
Well, the vacuum pump that came fitted with your machine is DESIGNED
for a MAXIMUM of 25" !!! There are good reasons for this, but I leave
that for another time.

In my MANY years of experience, lack of vacuum (or perceived lack of
it) is the LEAST important. Even at 20" you should be getting a ,
well, reasonable fill.

Before you do anything else, check for OTHER reasons for a non-fill.

  1. Are you leaving AT LEAST 1 1/4 " of bare center sprue (near the
    rubber base) before you begin mounting your waxes?

  2. In your effort to get a fill are your raising the metal
    temperature too much? It is always better to SLIGHTLY overtemp. the
    investment (remember, it has already been at a higher temperature. It
    has now ramped DOWN to your casting temp.)than the metal, that is if
    you must.

  3. Are you using “standard” flasks, the ones without the holes in the
    sides? If you are using the perforated flasks, are the holes LARGE
    enough? Yes, I know about vacuum acting practically statically and
    all that, but with a lowered vacuum, you still need to get the gasses
    out fast! If the holes in your flasks are small, get them drilled out
    to dime-sized or even larger. This will do no harm. Except to the
    drill bits :slight_smile:

  4. Are you using the correct crucibles? MEMCO has separate hole sizes
    for silver, and for gold, to (rather simply!) control flow rates.

  5. Are you using good metals, alloys?

  6. MOST IMPORTANT!!! Is there sufficient forming gas supply,
    reaching the melt? If you are using broken gas straws, then this is
    definitely not happening. If there is no supplier of forming gas in
    your region, get a gas mixer from MEMCO, and mix your own from
    separate cylinders (tanks). Good flow of forming gas at the melt will
    improve your castings unbelievably. I cannot overemphasize the role
    of forming gas in the use of MEMCO machines. It is SIMPLE to get
    perfect castings every time.

  7. As a last resort, you could replace the internal 25" vacuum pump,
    with an external 29" pump. But this is really not necessary; do it if
    it makes you feel better :slight_smile:

If you replace your MEMCO with any machine using carbon crucibles and
’inert’ gas it will be a backward step. The MEMCO is a highly
underestimated machine. It is capable of the finest possible work,
bar none. The combination of bottom-pour (now being regularly
copied)crucibles, elimination of ANY carbon, graphite etc. coming in
contact with the melt, ceramic crucibles, ACTIVELY REDUCING forming
gas cover, and accurate temperature measurement from inside the melt
(also increasingly used - but with a huge blob of graphite between
the t/c and the gold), is unbeatable. I HAVE NEVER BEEN HAPPY WITH
ANYTHING ELSE.

The only thing better than an ElectroVac, is an InductoVac; and that
ONLY if you have IMMENSE casting needs/capacity. I know casters using
an ElectroVac for over thirty casts a day (in two shifts, with a
cooldown period).

The InductoVac can do 120+ flasks without it, or the caster, breaking
a sweat!

Stick with it.

Good luck.

Nariman.

Dear Dominion,

You have been using a MEMCO ElectroVac. This means, you are using
non-graphite, ceramic crucibles; and using Forming Gas (a kinda-sorta
substitute for cracked ammonia, the preferred atmosphere for
production jewelers). This means you are by now used to troublefree,
micro-porosity-free (or as near to that as dammit!) castings, which
you are NOT going to get out of equipment using graphite crucibles
with or without Argon, Nitrogen or whatever.

You are about to let go of these tremendous advantages, because at
your geographical elevation you are not getting “enough vacuum”.
Well, the vacuum pump that came fitted with your machine is DESIGNED
for a MAXIMUM of 25" !!! There are good reasons for this, but I leave
that for another time.

In my MANY years of experience, lack of vacuum (or perceived lack of
it) is the LEAST important. Even at 20" you should be getting a ,
well, reasonable fill.

Before you do anything else, check for OTHER reasons for a non-fill.

  1. Are you leaving AT LEAST 1 1/4 " of bare center sprue (near the
    rubber base) before you begin mounting your waxes?

  2. In your effort to get a fill are your raising the metal
    temperature too much? It is always better to SLIGHTLY overtemp. the
    investment (remember, it has already been at a higher temperature. It
    has now ramped DOWN to your casting temp.)than the metal, that is if
    you must.

  3. Are you using “standard” flasks, the ones without the holes in the
    sides? If you are using the perforated flasks, are the holes LARGE
    enough? Yes, I know about vacuum acting practically statically and
    all that, but with a lowered vacuum, you still need to get the gasses
    out fast! If the holes in your flasks are small, get them drilled out
    to dime-sized or even larger. This will do no harm. Except to the
    drill bits :slight_smile:

  4. Are you using the correct crucibles? MEMCO has separate hole sizes
    for silver, and for gold, to (rather simply!) control flow rates.

  5. Are you using good metals, alloys?

  6. MOST IMPORTANT!!! Is there sufficient forming gas supply,
    reaching the melt? If you are using broken gas straws, then this is
    definitely not happening. If there is no supplier of forming gas in
    your region, get a gas mixer from MEMCO, and mix your own from
    separate cylinders (tanks). Good flow of forming gas at the melt will
    improve your castings unbelievably. I cannot overemphasize the role
    of forming gas in the use of MEMCO machines. It is SIMPLE to get
    perfect castings every time.

  7. As a last resort, you could replace the internal 25" vacuum pump,
    with an external 29" pump. But this is really not necessary; do it if
    it makes you feel better :slight_smile:

If you replace your MEMCO with any machine using carbon crucibles and
’inert’ gas it will be a backward step. The MEMCO is a highly
underestimated machine. It is capable of the finest possible work,
bar none. The combination of bottom-pour (now being regularly
copied)crucibles, elimination of ANY carbon, graphite etc. coming in
contact with the melt, ceramic crucibles, ACTIVELY REDUCING forming
gas cover, and accurate temperature measurement from inside the melt
(also increasingly used - but with a huge blob of graphite between
the t/c and the gold), is unbeatable. I HAVE NEVER BEEN HAPPY WITH
ANYTHING ELSE.

The only thing better than an ElectroVac, is an InductoVac; and that
ONLY if you have IMMENSE casting needs/capacity. I know casters using
an ElectroVac for over thirty casts a day (in two shifts, with a
cooldown period).

The InductoVac can do 120+ flasks without it, or the caster, breaking
a sweat!

Stick with it.

Good luck.

Nariman.

Dear Mr. Wadia, I was skimming the ganoksin web site and found your
response regarding Memco verses other casting machines and I wanted to
write you for clarification on some of these issues. I find some of
your points very interesting starting with your opinion that ceramic
crucibles and forming gas are a better “system” than any other truly
closed system-casting machine using an inert gas for protection. As
the ceramic crucibles are four to five times the cost of the graphite,
yet do not have four to five times the life, I am uncertain how this
can be of any advantage. I constantly hear from uninformed people that
graphite inclusions are found on pieces from machines using graphite
crucibles, however this is highly unlikely, (unless you are using an
inferior material). As any graphite (or carbon) that might remain in
the melt “floats” on the surface and rises to the button, it is next
to impossible to have graphite inclusions on the pieces. Also due to
the extremely high melting temperature of graphite, it is also very
unlikely that the graphite would meld with the material you are
casting with. More on this subject can be found in the Santa Fe
Symposium available through Rio Grande. You may want to
go to this, as it is very informative and there are many industry
experts much more knowledgeable than I am. The last point I would like
to make about the graphite crucibles is that they actually do serve a
purpose. The graphite will scavenge any remaining or trapped oxygen
from the metal during the melting process and provides chemical
reduction of metal oxides. You do not get that with ceramic
crucibles. Bottom pour crucibles have been around much longer than
Memco has been producing machines. As a matter of fact, most of the
original machines manufactured long ago used this same principal, so I
did not understand the comment of Memco’s crucibles now being
regularly copied.(?) If I am not mistaken, the thermocouple on the
Memco does slide down into a tube that is placed in the crucible, very
similar to any other bottom read system. However, I do not understand
how the Memco measures the temperature so accurately when it uses an
archaic control unit. As a test on a Memco, or any machine for that
matter, use a quick read pyrometer and a direct dip thermocouple on
various melts and see how close the temperature is to the controller
on the machine. I have done this on various machines, (including
Memco) and have yet to find one that is as accurate as the Neutec/USA
machines.

You then discussed some points that I also find intriguing. 1. The
first was you recommend leaving 1 �" of bare center sprue toward the
button on your tree, as your current machine is not able to
completely fill to the button. I am assuming your point is that the
metal begins to freeze before it gets to that part of the tree, thus
you feel you must leave that space free of pieces. I understand that
Memco’s temperature control is as I said before, somewhat archaic
however this is a great “waste” of metal, as you must fill all the
bare area as well. When using the Neutec/USA machines, and the
NeuSprue treeing system, you can sprue nearly to the button, (which
contains less metal than the traditional main tree button) thus you
have more product with better fill and less “scrap” per cast. This
cuts the number of trees daily, which in turn saves in investment as
well as metal in process, and you don’t have as much “used” metal to
deal with. Because you use less flasks, there is less labor cost built
into each cast and the savings goes on and on, yet we can discuss that
later if you would like. 2. You suggested SLIGHTLY overheating the
investment to help with fill. There are arguments both ways with this
however I personally prefer to increase the metal temperature (if
either), as the flask retains the heat longer, which can create other
issues. 3. The size of the holes in the perforated flasks may not be
as critical as how well they are placed and the sheer number in each
flask, and there are other key points , which I am sure you are aware
of. Even with a “lowered” vacuum, a 30 second draw down time is more
than sufficient to completely evacuate the gases to allow for little
resistance in the metal flow into the flask. Keep in mind; investment
even under a vacuum takes at least a few minutes to cool in the area
around the pieces. 4. I find it interesting that Memco has different
crucible hole sizes for different alloys. You say the purpose is to
control the flow rates yet most other machine manufacturers recognize
that the metal will flow at a certain rate unless it is placed under
pressure and there is no need for different size holes for different
alloys. Neutec has two different crucibles with different hole sizes
however this is only for the different tree size one might use. 5. Your
point five is where I am in total agreement with you. There are so
many alloys to choose from and it is sometimes very difficult to find
a reliable material for all your patterns. It is a trial and error
situation however the right casting machine with accurate temperature
control can definitely take some of the guesswork out of it. 6. Forming
gas? Does it not make more sense to have the entire melt and pour
area completely oxygen free as most of the advanced technology
machines are doing these days? And pushing a forming gas over the
surface of the metal does not completely eliminate the oxygen that is
trying to attack your melt as well as, what exactly does the forming
gas do to help you get porosity free castings? I have yet to see a
better finished casting due to any type of gas or other influence in
that area. Also, using two different gases, storing two different
tanks and /or using a gas mixing unit seems like a lot of hassle for a
relatively un-leak proof system. Neutec’s closed system approach is
unsurpassed in reducing or eliminating oxides from the melt. 7. You
mentioned this earlier however I would like to ask that you explain to
me (as I truly do not know) what the advantage is to having a vacuum
pump achieve a maximum of only 25" of mercury. That seems to defy all
logic when casting jewelry on any type of machine. I look forward to
your response on this subject.

Now when we talk about speed, I know that Neutec machines have the
fastest flask-to-flask time cycles and are the most controlled
machines in the world today. I have spoken with customers that are
producing up to 30 flasks per hour without any down time and because
the Neutec J-Series machines auto-cast, one operator can run two
machines; imagine the savings that creates. Even the J-2R can cast a
flask every 6-8 minutes and can run all day without any "cool down"
period, and the new J-z is a manual cast unit that can out produce
many machines costing two and three times it’s cost.

I look forward to your response as there are a few very interesting
points that you brought up and I would love to get some feedback.
Please feel free to contact me at my mail address so that we can
discuss these points further.

Regards, Joe Lovato