Is this a good/bad idea? I thought I remembered reading this was a cheap alternative... ?
Cooking spray for mold release?
- Thread starter Hecubus114
- Start date
I've also heard of people doing it too, I've tried it once when I ran outa release and the cast came out bad, weird surface with holes and whatnot
hmmm - anybody know of anything else? I want to make a mold tonight but dont have any spray... something I can run out and buy???
SUPERprops
Sr Member
cocoanut oil??? idk if it works, defiantly worth a try tho..
jedimaster
Sr Member
On ep2 and 3 margerine was also used when there was no wax or spray release. Worked fine.
I don't know what you’re moulding, but I've never used release agent with silicon and polyurethane resins, and I've never had anything stick together.
As a result I don't have any of the difficulty of having to get it of my mouldings either.
Occasionally on something tricky, a thin coat of Vaseline applied with a brush and evened out with a hairdryer has worked out okay!
As a result I don't have any of the difficulty of having to get it of my mouldings either.
Occasionally on something tricky, a thin coat of Vaseline applied with a brush and evened out with a hairdryer has worked out okay!
TheSt.LouisKid
Sr Member
What are you guys casting that needs mold release?
I'm not putting you down but in all my years I have never needed it.
In one shop I worked in back in the early '90's the person who did the casting used mold release and reapplied it for each new casting making each new casting look nastier than the next. Those of us prepping the parts wasted obscene amounts of time sanding castings to look normal getting rid of the eggshell suface and crisping/redefining the detail that the release had washed out. This all translated into wasted time. They never cleaned the release out of the mold and if they did it would mean more wasted time in getting every bit of release out for the next part. Seeing how much time was wasted they finally came to their senses and stopped using it.
But at that shop I mentioned and even my own projects I have always cast mechanical looking items for the most part. Even when I worked at McFarlane Toys the mold shop never used mold release and they were casting people with hair and other fine details, animals, and other items representing living things/non mechanical forms.
Mez7 mentioned baby powder. On another releated thread I mentioned this is effective by itself for less bubbles but use cornstarch based powder. The talc based powder will accumulate in your lungs and NEVER go away which is why hospital nursuries don't use it.
I'm not putting you down but in all my years I have never needed it.
In one shop I worked in back in the early '90's the person who did the casting used mold release and reapplied it for each new casting making each new casting look nastier than the next. Those of us prepping the parts wasted obscene amounts of time sanding castings to look normal getting rid of the eggshell suface and crisping/redefining the detail that the release had washed out. This all translated into wasted time. They never cleaned the release out of the mold and if they did it would mean more wasted time in getting every bit of release out for the next part. Seeing how much time was wasted they finally came to their senses and stopped using it.
But at that shop I mentioned and even my own projects I have always cast mechanical looking items for the most part. Even when I worked at McFarlane Toys the mold shop never used mold release and they were casting people with hair and other fine details, animals, and other items representing living things/non mechanical forms.
Mez7 mentioned baby powder. On another releated thread I mentioned this is effective by itself for less bubbles but use cornstarch based powder. The talc based powder will accumulate in your lungs and NEVER go away which is why hospital nursuries don't use it.
I have always used release on any mold I've don, even if it's tin based, all my cast have come out super clean, never any bubbles or coating even on a straight down pour, and especially when I pour something with a lot of small undercuts, I don't want to have it sticking and ripping the silicone, I've visited a lot of production companies up in Vancouver and LA and they always use release too, why not?
exoray
Master Member
If you use it religiously it will extend the life of a silicone mold as it prevents the permeation of the resin into the surface of the silicone that dries out the mold...
And I have found you can double the remaining pulls out of dying mold if you use release...
As for it messing with the surface, that depends on the release being used, using some of the fine misted spray paraffin and/or polymer based releases results in nil surface issues... A heavy or bush on coat, yeah it messes with things...
Three reasons I use it on a master before molding...
1. To simply aid when removing the master from the mold, a good Carnauba wax job or spray release really aides in removal...
2. It can also be used as a surface sealer for porous materials like plaster or wood that I have found silicone will sometimes seep into and bind...
3. To provide a barrier from possible cure inhibition, and surprisingly there are several things that will play havoc with curing, especially with the platinum cure silicones... I almost always use it on a piece I'm not familiar with and isn't mine... God knows what might be on the surface or what chemical substance might be present... Especially on an organic or natural piece that you don't know the composition of... Clear coating or painting isn't always an option, but you might be able to get by with a misting of paraffin...
Well I don't know what the secret is for all the guys who never use mold release - I've had polyurethane rubber stick to resin... Bad. My project lastnight was molding a resin piece which I had primed and sanded several times. The rubber mold was stuck so bad today that it was impossible to remove without destroying. It was very strange - it almost seemed like the smoothest parts were where it stuck the worst. In the end the whole project was ruined 
. From now on everything is getting a generous coat of release spray...
. From now on everything is getting a generous coat of release spray...What material are you casting? In most circumstances yes, plaster is very porous and will absorb liquids. Great for casting latex but with resins/silicone/urethane rubber etc you will need to at least properly seal it.
Risu
Master Member
I'll be using Onyx resin in the plaster mold.
exoray
Master Member
Why, are you using plaster?
Chances are you might get one or two pulls out of it if you are lucky before it crumbles when you attempt to dislodge the casting...
But, if you still want to move forward with the plaster, seal it with a good clear coat, and then multiple coats (4 plus) of Carnauba wax between castings, cross your fingers and hope for the best...
Another option is to flood the plaster with Vaseline, and run a hairdryer or heat gun over it to smooth it out, and then rub and buff a coat of fresh Vaseline into it before casting...
I have done this for quick and dirty one offs but it's really a **** pour choice for replication of a part in a hard cast, works for latex and the sorts though as it wicks out the water and allows for breathing... But for casting a solid part in resin, I wouldn't even waste my time, the aggravation will far out weigh the cost of the silicone...
