Moulds

"Liam Striker" wrote in message
. ..
1/32 fiber source


http://www.mertons.com/Additives/milled.html

My goodness, I will sell direct for those prices too, and I will cover the
shipping!! My last 50 lb bag cost $70.00, and when I drive to Eastpointe,
(Detroit) I pay $105 for a 50 lb. That's name brand stuff, the cheap works
good too.

Let me know what you want and I will disperse as needed. $3.50 per lb is
nuts. Or if your selling it, good profit.

Typically a single use plaster mold is made by mixing equal parts of #1
pottery plaster and 325 mesh silica. Hydroperm seems to be a popular
substitute for the pottery plaster but I don't like it as much. Set up
your model in a retainment ring making sure it is anchored to the base
and seal all the edges along the ring with hot glue; clay may work but
you'll find out soon enough that hot glue is better. In a large
container put water to about 1/2 the anticipated volume. Now, using a
flower sifter, sift the pre-mixed plaster/silica into the water SLOWLY!
As you increase the mix the plaster will be absorbed more slowly. Keep
at it until the plaster stays on the surface with little lines running
through it. Try to get that surface as level as you can with your
sifting. Go away for three minutes, or go apply separator to your model.

The next step is controversial and that's the mixing part. Some books
say to use an electric drill with a special blade, and if you do you are
sure to whip the mix into a froth which will leave plenty of air
bubbles. There's another thread going about all this. I mix by hand.
Roll up my shirt sleeve and go to work. I like doing it this way
because it lets me feel the lumps and squeeze them out. I don't get
bubbles this way either; no lumps, no bubbles = better finished product.

Plaster needs to dry before you use it. Depending on the size of the
mold I may let one dry for several weeks. If it isn't too big, demold
after a couple of hours and set it on top of your kiln while you do
several firings. It will still need kiln drying and you do that by
putting it in the kiln at 50 degrees per hour to 225 and holding it
there until it's dry. How long is that? Well I program for about three
times longer than I think I need and then check it by using a mirror
over one of the peep holes. If you get condensation on the mirror, you
ain't done yet. After that, you need to go to 325 to get out all the
chemically bound water; hold there for 1/3 the time you spent at 225.
Finally, go up SLOWLY to 1200 for the final curing (100 dph works well)
and hold there for about the same time you held at 325. Beyond that,
the mold is cured and your only consideration is the glass.

This is a conservative schedule which others may say takes too much
time. Well, considering all the time you've got in making your model
and getting it into the plaster, doesn't it make sense to play it a
little safe?

Good luck,
Jerry

Elaine Coggins wrote:

Can any one in the group give me a recipe for making a high temperature
plaster mould, also firing temp, for a slump mould for glass?

-- Yours in Art Elaine.
E.M.Coggins





--
? Angel Antics Glass Crafters ?
Fine Art Glass, Kaleidoscopes and
Tiffany Lamp Reproductions
Jerry & Ann Maske
3 Garden Way
Sullivan, ME 04664
Phone (207) 422-2250
Email
Web site http://www.angelantics.net/

Nice words, Jerry,

You could write a book about your methodology.
Very well researched, tested and written. The
best and most complete information on making
a mold that I have read. Into the file you go!

Hal

"Jerry Maske" wrote in message
...
Typically a single use plaster mold is made by mixing equal parts of #1
pottery plaster and 325 mesh silica. Hydroperm seems to be a popular
substitute for the pottery plaster but I don't like it as much. Set up
your model in a retainment ring making sure it is anchored to the base
and seal all the edges along the ring with hot glue; clay may work but
you'll find out soon enough that hot glue is better. In a large
container put water to about 1/2 the anticipated volume. Now, using a
flower sifter, sift the pre-mixed plaster/silica into the water SLOWLY!
As you increase the mix the plaster will be absorbed more slowly. Keep
at it until the plaster stays on the surface with little lines running
through it. Try to get that surface as level as you can with your
sifting. Go away for three minutes, or go apply separator to your model.

The next step is controversial and that's the mixing part. Some books
say to use an electric drill with a special blade, and if you do you are
sure to whip the mix into a froth which will leave plenty of air
bubbles. There's another thread going about all this. I mix by hand.
Roll up my shirt sleeve and go to work. I like doing it this way
because it lets me feel the lumps and squeeze them out. I don't get
bubbles this way either; no lumps, no bubbles = better finished product.

Plaster needs to dry before you use it. Depending on the size of the
mold I may let one dry for several weeks. If it isn't too big, demold
after a couple of hours and set it on top of your kiln while you do
several firings. It will still need kiln drying and you do that by
putting it in the kiln at 50 degrees per hour to 225 and holding it
there until it's dry. How long is that? Well I program for about three
times longer than I think I need and then check it by using a mirror
over one of the peep holes. If you get condensation on the mirror, you
ain't done yet. After that, you need to go to 325 to get out all the
chemically bound water; hold there for 1/3 the time you spent at 225.
Finally, go up SLOWLY to 1200 for the final curing (100 dph works well)
and hold there for about the same time you held at 325. Beyond that,
the mold is cured and your only consideration is the glass.

This is a conservative schedule which others may say takes too much
time. Well, considering all the time you've got in making your model
and getting it into the plaster, doesn't it make sense to play it a
little safe?

Good luck,
Jerry

Elaine Coggins wrote:

Can any one in the group give me a recipe for making a high temperature
plaster mould, also firing temp, for a slump mould for glass?

-- Yours in Art Elaine.
E.M.Coggins





--
? Angel Antics Glass Crafters ?
Fine Art Glass, Kaleidoscopes and
Tiffany Lamp Reproductions
Jerry & Ann Maske
3 Garden Way
Sullivan, ME 04664
Phone (207) 422-2250
Email
Web site http://www.angelantics.net/

"Jerry Maske" wrote in message
...
Typically a single use plaster mold is made by mixing equal parts of #1
pottery plaster and 325 mesh silica. Hydroperm seems to be a popular
substitute for the pottery plaster but I don't like it as much. Set up
your model in a retainment ring making sure it is anchored to the base
and seal all the edges along the ring with hot glue; clay may work but
you'll find out soon enough that hot glue is better. In a large
container put water to about 1/2 the anticipated volume. Now, using a
flower sifter, sift the pre-mixed plaster/silica into the water SLOWLY!
As you increase the mix the plaster will be absorbed more slowly. Keep
at it until the plaster stays on the surface with little lines running
through it. Try to get that surface as level as you can with your
sifting. Go away for three minutes, or go apply separator to your model.

The next step is controversial and that's the mixing part. Some books
say to use an electric drill with a special blade, and if you do you are
sure to whip the mix into a froth which will leave plenty of air
bubbles. There's another thread going about all this. I mix by hand.
Roll up my shirt sleeve and go to work. I like doing it this way
because it lets me feel the lumps and squeeze them out. I don't get
bubbles this way either; no lumps, no bubbles = better finished product.

Plaster needs to dry before you use it. Depending on the size of the
mold I may let one dry for several weeks. If it isn't too big, demold
after a couple of hours and set it on top of your kiln while you do
several firings. It will still need kiln drying and you do that by
putting it in the kiln at 50 degrees per hour to 225 and holding it
there until it's dry. How long is that? Well I program for about three
times longer than I think I need and then check it by using a mirror
over one of the peep holes. If you get condensation on the mirror, you
ain't done yet. After that, you need to go to 325 to get out all the
chemically bound water; hold there for 1/3 the time you spent at 225.
Finally, go up SLOWLY to 1200 for the final curing (100 dph works well)
and hold there for about the same time you held at 325. Beyond that,
the mold is cured and your only consideration is the glass.

This is a conservative schedule which others may say takes too much
time. Well, considering all the time you've got in making your model
and getting it into the plaster, doesn't it make sense to play it a
little safe?

Good luck,
Jerry


Thanks Jerry but who has the time for all this, and still be able to make
a profit? I put paper tape around my piece, mixup Hydroperm with my wifes
old hand mixer, and pour it on about 1-2" deep. About 30 minutes later the
tape comes off and the glass separated from the mold. I either let it dry
overnight, in the sun, or about 200 degrees for a few hours and it's ready
to fire!

--
JK Sinrod NY
Sinrod Stained Glass
www.sinrodstudios.com
Coney Island Memories
www.sinrodstudios.com/coneymemories

jk wrote:

Thanks Jerry but who has the time for all this, and still be able to make
a profit? I put paper tape around my piece, mixup Hydroperm with my wifes
old hand mixer, and pour it on about 1-2" deep. About 30 minutes later the
tape comes off and the glass separated from the mold. I either let it dry
overnight, in the sun, or about 200 degrees for a few hours and it's ready
to fire!


On the link below is a picture of cast leaves. That went from concept to
clay model, to plaster/silica mold, to glass loading, to firing all in
about 3 hours. A couple hour hold in the 200-300 range after the glass
was in the mold worked just fine. Just make sure to vent the kiln.


--
Jack


http://photos.yahoo.com/bc/xmissionbobo/

On the link below is a picture of cast leaves. That went from concept to
clay model, to plaster/silica mold, to glass loading, to firing all in
about 3 hours. A couple hour hold in the 200-300 range after the glass
was in the mold worked just fine. Just make sure to vent the kiln.


Speaking of venting of the kiln, hoiw do you vent that big box of yours?
Got a hole and plug in the top?

Javahut wrote:


On the link below is a picture of cast leaves. That went from concept to
clay model, to plaster/silica mold, to glass loading, to firing all in
about 3 hours. A couple hour hold in the 200-300 range after the glass
was in the mold worked just fine. Just make sure to vent the kiln.


Speaking of venting of the kiln, hoiw do you vent that big box of yours?
Got a hole and plug in the top?

Right now I just leave the bell 1/2" off the bed. This was an oversight
on my part. I have work to do under the bell soon. I'm going to trim the
frax from 4" to 2" thick on the lower 4" of the rim. This will allow the
large fiber kiln shelf to fit inside. The shelf was given to me after I
built the bell. While under there I will install some sort of vent on
the side wall at the top. Probably one each end. Or maybe a SS tube with
holes that I can feed low pressure air. The only thing holding me back
is that I haven't welded my safety chains on yet and I'm not about to
get in that mouse trap without safety devices.

In another thread it said something about you being everywhere. A few
weeks back I saw Elvis, Jimmy Hoffa, and Javahut in the parking lot of a
7-11 in Boise Idaho. When I tell people about it they say "There's no
way you saw Javahut in Boise".
--
Jack


http://photos.yahoo.com/bc/xmissionbobo/

The only thing holding me back
is that I haven't welded my safety chains on yet and I'm not about to
get in that mouse trap without safety devices.

No guts, no glory, ( I wouldn't do it either!)

In another thread it said something about you being everywhere. A few
weeks back I saw Elvis, Jimmy Hoffa, and Javahut in the parking lot of a
7-11 in Boise Idaho. When I tell people about it they say "There's no
way you saw Javahut in Boise".

Only the shadow knows....... nad he knows the perch are starting in Lake
Erie, the fall Walleye are at Huron, Ohio, in Lake Erie, and the Lake Huron
Salmon are getting into the rivers. and the steelehead are fast
approaching. Michigan is a great place in the fall!

Javahut wrote:

The only thing holding me back
is that I haven't welded my safety chains on yet and I'm not about to
get in that mouse trap without safety devices.

No guts, no glory, ( I wouldn't do it either!)

In another thread it said something about you being everywhere. A few
weeks back I saw Elvis, Jimmy Hoffa, and Javahut in the parking lot of a
7-11 in Boise Idaho. When I tell people about it they say "There's no
way you saw Javahut in Boise".

Only the shadow knows....... nad he knows the perch are starting in Lake
Erie, the fall Walleye are at Huron, Ohio, in Lake Erie, and the Lake Huron
Salmon are getting into the rivers. and the steelehead are fast
approaching. Michigan is a great place in the fall!

Indeed it is. I haven't seen one cider mill here in Utah and perch are
considered trash fish. It's been almost 10 years since I was in Michigan
in October.
--
Jack


http://photos.yahoo.com/bc/xmissionbobo/

"nJb" wrote in message
...
jk wrote:

Thanks Jerry but who has the time for all this, and still be able to
make
a profit? I put paper tape around my piece, mixup Hydroperm with my
wifes
old hand mixer, and pour it on about 1-2" deep. About 30 minutes later
the
tape comes off and the glass separated from the mold. I either let it
dry
overnight, in the sun, or about 200 degrees for a few hours and it's
ready
to fire!


On the link below is a picture of cast leaves. That went from concept to
clay model, to plaster/silica mold, to glass loading, to firing all in
about 3 hours. A couple hour hold in the 200-300 range after the glass
was in the mold worked just fine. Just make sure to vent the kiln.


--
Jack


http://photos.yahoo.com/bc/xmissionbobo/

Looks like 3 fine looking dogs to me?

--
JK Sinrod NY
Sinrod Stained Glass
www.sinrodstudios.com
Coney Island Memories
www.sinrodstudios.com/coneymemories