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Cliff
08-02-2012, 04:27 PM
i have cast my first few mask and im noticing on my 2nd pull they are more difficult to pull then my first, is there something that will work as a mold release on the self at walmart. i dont really want to have to buy it online but if i do who has it cheap!! thanks for the help guys!!

Infoamtek
08-02-2012, 10:08 PM
What is the mold made of and what are you casting with?

Cliff
08-02-2012, 11:19 PM
mold is made of Ultra cal 30 and pulling mask latex

Allen H
08-02-2012, 11:22 PM
You should not need a release at all for that. Make sure the cast id completely dry and you should be fine.

Cliff
08-02-2012, 11:30 PM
thanks! i think maybe the 2nd time i had the latex to thin!! Hey Allen should have you new DVD showing up here in the next day or two. really looking forward to it. thanks again!

Infoamtek
08-04-2012, 03:20 PM
Any mold release will inhibit the absorption of the liquid and keep the latex from getting any thicker than a very thin skin. Because any plaster is absorbent, there will always be a little pullback when demolding, especially if there is a lot of texture. It's normal.

Cliff
08-04-2012, 10:28 PM
thank you guys

DarkShado
08-15-2012, 07:33 AM
ALL molds need release agents, except for some silicone applications. Especially if they are not sealed.

Use steric acid. It is normally used as a release agent for GM foam latex. It is available from Alcone. It is cheap and works well for absorption casting.
www.alconeco.com

Derek B.

Allen H
08-15-2012, 08:56 AM
No, they do not. Unless the thousand or so masks I have pulled from my plaster molds have been a fluke.

DarkShado
08-15-2012, 09:26 AM
If you use a release agent, the molds and the pieces pulled from those molds will be a better quality and last longer, that is why they make it.
Does your piece have a white dust on the surface when you pull it? That white color is the surface of you mold.

Slush latex it more forgiving. It is great for first timers.

Try your technique in ANY with any other medium and your pieces will not look as good as the sculpture, if you can get them out. Also your molds life will be GREATLY decreased. Who wants to re-sculpt?

I rather pull a thousand pieces from one mold then one piece from a thousands molds.

Allen H
08-15-2012, 10:37 AM
Dark Shado-
I work very hard to answer the question as it was asked, unless it completely makes no sense.
"If you use a release agent, the molds and the pieces pulled from those molds will be a better quality and last longer, that is why they make it. "
Untrue. Most companies make products in order to make money, in many cases a drastically cheaper mold release is already available but they lead people to believe that mold releases are proprietary and you need to use their product. Some things needs a release agent, the question was for a latex mask from a plaster mold and the answer in that case is no.

"Does your piece have a white dust on the surface when you pull it? "
Mine do not, as the latex cures it pulls itself away from the mold so there is little contact with the molds surface by the time I pull it. The pull away is a result of the latex shrinking as it dries.


"Slush latex it more forgiving. It is great for first timers."
I actually think a 50/50 silicone mold with resin pours are easier for first timers- less time for making the mold and they can get the concept of pull with a flexible mold material. It helps them understand how undercuts could be a problem if the mold were not flexible. Gel-10 as the mold makes an easy mix and easy pours and release.
Slush Latex is fairly forgiving, but this is not a first timer issue, it is a need issue. If you need a latex mask, then a plaster mold is the way to go. I always recommend a dwell time as opposed to a slush cast because of the even thickness you will achieve.

"Try your technique in ANY with any other medium and your pieces will not look as good as the sculpture, if you can get them out."
I have silicone molds that I have had hundreds of pulls from with no release those were all resin pulls. There is of course a time and a place for mold release but this time, this question the answer is no. The answer is really no when you consider the second part of the question which was available at Walmart.

"Also your molds life will be GREATLY decreased. Who wants to re-sculpt?"
there are no absolutes in anything- as soon as you speak in absolutes you become slightly wrong. You can decrease the life of your mold, but in some cases it is fine to use no release. The wrong advice on release and the mold is ruined so with no release there is no risk. Example- plaster mold wanting a latex pull. If someone uses johnsons paste wax as a release then the mold will not pull a latex mask effectively because the wick-ing action is slowed/stopped. Dish soap could do the same thing to your mold- So to advise no release mitigates the risk.
Once you are working with silicones many materials will inhibit the cure of platinum silicone, so even release agents need care.

"I rather pull a thousand pieces from one mold then one piece from a thousands molds."
On this we agree.

Allen H

DarkShado
08-15-2012, 12:15 PM
I am here to help. If I need to defend what I know then……

Untrue. Most companies make products in order to make money, in many cases a drastically cheaper mold release is already available but they lead people to believe that mold releases are proprietary and you need to use their product. Some things needs a release agent, the question was for a latex mask from a plaster mold and the answer in that case is no.


All companies make products to make money. Steric acid is extremely cheap. It is meant for foam latex but you can use it for slush latex. It is the same thought as using PAM cooking spray in your buckets before mixing the plaster in order to release it. It is meant for cooking but can be used in mold making. Try brushing in latex in a mold and try to remove it without a release. Is you piece all distorted now?



"Does your piece have a white dust on the surface when you pull it? "
Mine do not, as the latex cures it pulls itself away from the mold so there is little contact with the molds surface by the time I pull it. The pull away is a result of the latex shrinking as it dries.


The latex you are using has a HIGH amount of water in it that is why it shrinks. I wouldn’t count that as a plus. The final piece is not what was sculpted which means a poor fit for the actors.



"Slush latex it more forgiving. It is great for first timers."


For make a positive casting, masks.



I actually think a 50/50 silicone mold with resin pours are easier for first timers- less time for making the mold and they can get the concept of pull with a flexible mold material. It helps them understand how undercuts could be a problem if the mold were not flexible. Gel-10 as the mold makes an easy mix and easy pours and release.


Silicone leaches it own release agent, acetic acid. That is the KEY aspect in silicone rather than urethanes. Urethanes are also flexible and cheaper than silicone. Not to mention much higher tear strength. You also need a triple beam balance to mix the parts correctly, ANYONE can pour into a box.



Slush Latex is fairly forgiving, but this is not a first timer issue, it is a need issue. If you need a latex mask, then a plaster mold is the way to go. I always recommend a dwell time as opposed to a slush cast because of the even thickness you will achieve.



Dwell time = The time cargo remains in a terminal's in-transit storage area while awaiting shipment by clearance transportation. I have no idea what you are talking about. I think you mean, leaving the latex in the mold in order for it to be absorbed. The longer the latex in kept in the mold the more water is absorbed in to the plaster. The more porous mold will do a better job but will not last as long. Hence why it is called absorption casting. The choice of plaster affects the casting also. Pottery plaster work best, but limited castings, White Hydrocal is better, stronger but needs more absorption time. They there is Ultrcal 30, more dense, not worth doing absorption casting.



"Try your technique in ANY with any other medium and your pieces will not look as good as the sculpture, if you can get them out."
I have silicone molds that I have had hundreds of pulls from with no release those were all resin pulls. There is of course a time and a place for mold release but this time, this question the answer is no. The answer is really no when you consider the second part of the question which was available at Walmart.


Silicone leaches its own release agent, acetic acid.



"Also your molds life will be GREATLY decreased. Who wants to re-sculpt?"
there are no absolutes in anything- as soon as you speak in absolutes you become slightly wrong. You can decrease the life of your mold, but in some cases it is fine to use no release. The wrong advice on release and the mold is ruined so with no release there is no risk.


No risk – how about having to do it all again because you wanted to save cents. Beginner mistake.



Example- plaster mold wanting latex pull. If someone uses johnsons paste wax as a release then the mold will not pull a latex mask effectively because the wick-ing action is slowed/stopped. Dish soap could do the same thing to your mold- So to advise no release mitigates the risk.


Paste wax SEALS it along with releasing. Dish soap is used to keep the latex out of brushes and should NEVER be used as a release agent. Why would you want to introduce a foaming agent to the mix???





I have thought mold making/ make-up and special effect for over 20 years at numerous schools, universities, and conventions. My work has been in over 100 magazines, behind the scenes at Saturday Night Live and the Metropolitan Opera, and The Conan O'Brien Show to name a few. Also the 2 Emmy and Oscar nominations for my work. I also mass produced prosthesis for Graftobian and have been a consultant for Marty at Meheron, and Dana at Ben Nye, on mass production of their prosthetic pieces. I work for the Human Response Performance Labs for prosthesis for the University of Hartford. I know what I am talking about. If every statement needs to be defended, mine will be VERY few. I was tiring to help.

Keep a bucket of plaster near by to catch the tears for not listening, you can make a mold with the paste.

Derek Becker

Allen H
08-15-2012, 09:32 PM
Derek,
Lets try to get off on a better footing. I am also very experienced in mold and mask making. I am more of the quick and dirty when it comes to mask making/ everything. I have never used a release when pulling a latex mask from a plaster mold- so you can effectively pull latex masks from plaster molds without a release.
There is always more than one way to do things, I'm willing to bet we do them very differently- But I bet we both get them done. You went to fairly great lengths to be a dick in your last post- from that I can tell you are not afraid of hard work. We just work differently. I have no doubt that many of my techniques you will find appalling, and many of yours I will find a waste of time and effort. That is life and the way of things. Some readers will value your advice more and others will value my advice more.
I think we should make an effort to not be dicks to each other. There is no way for me to state my experience and not sound like I'm throwing my thing down so I wont. Im not back pedaling in the least- I have pulled a few thousand masks without a release- But I am very into trying new things so I will order some steric acid and check it out.
Allen H

P.S. You have really never heard of it referred to as dwell casting or dwell time? What part of the country are you in? I was first taught that term in FL but have heard it all over the mask industry.

Allen H
08-15-2012, 09:41 PM
~Im only posting this cause its funny- this was a good one~
"Keep a bucket of plaster near by to catch the tears for not listening, you can make a mold with the paste."

Actually you should always add plaster to the water not water to the plaster ;)

Greg Chrise
08-15-2012, 10:24 PM
The whole purpose of using plaster as a mold is something porous that can take the moisture content out of the latex and provide a high density end product that cures for sure. If you us any mold release you have blocked that way of curing. You then have no ability to tell how long it should sit to develop a certain thickness.

If something is popping off the surface as it cures, it is distorted as it sets. Maybe minor but it could just fall off if the mold is at a strange angle or you are doing slush casting and letting it cure out further once most of the latex has been removed.

Foam latex is using an oven to bake out the moisture and mold release is technically used so the foam does not bake onto the mold. Silicones and urethane castings as they chemically cure reach temperatures of 115 to 140 degrees and similar to baking so mold release is used there too.

Casting with latex has been done for more than 100 years now and you can use fish oil as a mold release or wale blubber if you wanted to. Neither one comes with a little instruction paragraph. Maybe a help me note from Captain Ahab.

The other reason to not use mold release is what ever was used is going to have to be nutralized or cleaned in order to paint over them. Or at least having something that will last and not nick easily. If you did a proper latex casting and the moisture went into the mold, you clean the mold and the end casting is very close to being ready to paint as it is bare and uncontaminated. This also applies for adding anything to the casting besides paint.

Getting only 15 or 25 pulls from a mold is what gives it some exclusive higher value. You can't be buying one of a couple thousand. Some detail might begin to become complicated with cleaning and demolding and so the every all design should be where detail is something added to the casting with each one being unique as an opportunity. Each unit becomes precious and numbered and if there are to be thousands, there is a master plug to remake more molds rather than rescultping over and over different versions.

This difference in quality is judging that something will be used on TV once for 2 minutes and you make 5 of them as back up or you have one mask that will be worn a couple years and see real mechanical fatique and scuffing or be on display for years. Mass produced 1000s of masks are $18, good quality are selling for $100 to $200. Mass produced ones with the wrong density start to dry out in 2 years. Old school masks have lasted 50 years and gone through restorations if they were important designs.

It actually doesn't take more time or care to provide better quality. Lots of people do things with a drill rather than get their hands in the plaster and such and end up with problems. Quick and dirty isn't necessarily bad. It is having the proper knowledge of with why products have been used in such a fashion and the history of why it is done in such a fashion. Anything that has the word acid in it is no longer archival, in other words it isn't going to last, something has been sacrificed. It might be fine for short term there it is, captured on video or film and throw it away, apply 3 a day shops.

For haunt applications, you are going to end up with some money invested, time invested and giving those pieces some history of being used in this or that haunt. They have an intrinsic value or the reputation of the artist at stake. So it is all more an application of how and where the end item is being used, or how significant the attachment to an item can be.

Greg Chrise
08-15-2012, 10:42 PM
It may seem quick and cheap to add a release agent but you really added untold labor in cleaning molds and preparing surfaces.

If you are not allowing the latex moisture cure to be drawn into the plaster mold, you are having to depend on humidity and forced drying with air and possibly thinner and several coats rather than one time with a dwell time being observed and you get a product out that is predictable in durometer and thickness.

DarkShado
08-16-2012, 05:23 AM
I'm sorry we did get off on the wrong foot.

The main question was about release agents to use or not. The down-n-cheap way is to not to use them. Of course it will work, just the life of the mold is decreased greatly. I think it is worth 1 dollar per mask. There is a recipe to make your own release agent for even a cheaper price. The word acid is used because of it PH balance. The main ingredient is animal fat, also used to make soap and candles.

A real down and dirty way would to just spray latex over the sculpture. Skip the mold. Alcones latex can be sprayed right out of the bottle. Here is the airbrush.
http://www.paascheairbrush.com/CatalogueRetrieve.aspx?ProductID=6107903&A=SearchResult&SearchID=2423872&ObjectID=6107903&ObjectType=27

I'll take your word on "dwell Time" the best meaning I found was " time delay during which an indenter is held against a material under load". I guess we can count atmospheric. Mainly used in the thermoplastics industry. When I get back to work I will have to ask to engineers this question. I also can also be wrong but also still love to learn. And I can also be a dick. Sorry to all offended.


p.s. Allen you got me in the plaster quote, touché

D

Greg Chrise
08-16-2012, 10:31 AM
Even animal fats with citric acid, ph balanced with sodium citrate compounds for even dispersal, is their task. That being said, you are into modified compounds as well to clean things. Then it gets weird and you are having to condition things with Naptha solvents, wax and grease remover thinners and exposing yourself to unhealthy smells regularly. Things that remove even soap scum are phosphates. In the modern world these things are used every day and no one questions them.

Dwell time refers to a substrate requiring time to absorb to it's utmost capacity. It takes time to observe that effect has occured and curing has begun. The curing with out moisture and how it has been accomplished lines up ions and molecule binders to some degree of efficiency. In Latex this translates to how much elasticity it will have and how many cycles it can be stretched before it becomes brittle. There is also a time clock where over years the molecular structure is continuing to modify, to continue to cure and binder parts and number of molecules becomes larger clumps until it is no longer just a grain and the chunky mass will crack when bent.


I have talked to engineers, they call me.

Marr Branch
08-16-2012, 11:51 AM
I think the longer Darkshadow follows the forums, He will figure out that Allen is a haunt genius.

DarkShado
08-17-2012, 04:53 AM
I know Allen knows his stuff. Does he know it all, no, but pretty damn close. I still feel I know more in mold making, so what......Not a bad thing.....

Dwell time refers to a substrate requiring time to absorb to it's utmost capacity. - Saturation time.

The curing with out moisture and how it has been accomplished lines up ions and molecule binders to some degree of efficiency. - called curing time

In Latex this translates to how much elasticity it will have and how many cycles it can be stretched before it becomes brittle. - called a fatigue cycle


I have yet to find any of these words used in conjunction or as a synonym with the word dwelling. Just having a hard time believing this one.

Side note:
Molecules mate by charge, not binders. = That is compounds.
In the curing of latex it is the PH that contributes to the curing not the charges of molecules (ions). Hint Ammonia base.
Why are we looking at latex at a molecular level. In the mold....dehydration synthesis is the process of curing in latex. Loss of water which is being absorbed by the mold.


This is now officially off topic. Done with this thread.

DK

Darksidestew
08-17-2012, 08:11 AM
I have been making molds for 30 years. when it comes to a ultra cal mold or plaster mold "ZERO" release agent is needed. Infact....if you use mold release with latex and ultra cal, the mask will take longer to dry and will not be as thick as it should be. As far as higher quality with a realease ....false....

Heres a good one- I use release on my latex mold that makes latex masks....
Did I just say that? Thats right...do it all the time...

darksidestew

Infoamtek
08-17-2012, 09:00 AM
Also Cliff, the earlier you pull a latex piece from the mold after it has been cured, the easier it is to pull.

Greg Chrise
08-17-2012, 06:30 PM
I was really hoping I could get a circle of 20 cats to focus on the ions of a mold and levitate the mask in the air with no release agent, just with mind control. Dissapointment.

Allen H
08-17-2012, 07:40 PM
"Heres a good one- I use release on my latex mold that makes latex masks....
Did I just say that? Thats right...do it all the time..."
What? you must elaborate if you are going to break the laws of mask making psychics. Even a pic of a finished mask using this method?

Darksidestew
08-17-2012, 08:19 PM
Here is a photo of a plaster bust of the hunchback .

13564135651356413565

Darksidestew
08-17-2012, 08:24 PM
5 or 6 coats of latex was applied to the plaster bust .

When the latex dried, polyfoam was poured over entire bust.

Now you have a nice durable flexible mold.

1356613567

Darksidestew
08-17-2012, 08:31 PM
I first sprayed the latex mold with flat clear, then a light ccoat of vaseline. It takes 3 to 4 days for latex to dry - be patient .
Unpainted Peg Leg Pyrat on the left, finished product on the right.


1356813569










thanks
Darksidestew

Allen H
08-17-2012, 09:04 PM
Okay, so a 3-4 day dry time. And it does not have super deep areas (long nose etc.) How thick are you going with the latex pull?

Darksidestew
08-17-2012, 09:10 PM
Its as thick as a high quality mask. I do have others Ive done with alot of detail. Did this because its all I had on hand at the time.

Thanks