In this video I'll show you how to thin silicone down to any viscosity. Pourable silicone is expensive so thinning down silicone will make it pourable for mold making. I'm using mineral spirits to thin silicone.
A mixing tip: you can stir forever and get frustrated, or you can put the silicone and the spirits into a plastic bag and squish it into submission. And have fun doing it too. The thicker parts are easier to target and squish into the spirits. And there is no doubt if it is fully mixed.
@@vdavis1959 Because I make a couple tablespoon worth at a time, my first reaction was a laugh. But for large quantities, that is an excellent suggestion! I wouldn't have thought of buckets and drill mixers.
How much does it shrink while curing? The mineral spirits evaporate off I presume. Most silicone caulk I've used contains acetic acid and cures by air drying.
There is a difference between the 2 commonly available silicones.. type 1 is perhaps less durable when exposed to UV/ sunlight.. that is why old silicone caulking often shrinks and peels.Type 1 however can be thinned easily with Naptha to about a 1 part Naptha to 5 parts type 1 (more Naptha if you are making it brushable for waterproofing) you can add cornstarch to the silicone and Naptha to add surface area .. it makes it firmer once it hardens.. this goes off in an hour or so and within 4 or five it is as hard as it will be ever.. Great for hobbies or things that will be indoors.. or for waterproofing textiles like tarps and tents.. Type 2 is almost the same thing but can have any number of things added to it like mold inhibitors, UV protection elements, adhesion promoters, etc. These things CAN make it harder to thin or make homogenous enough to cure properly. Mineral spirits may seem like a good choice over Naptha since it is less noxious and toxic.. however.. it often doesn’t cure as consistently.. especially if thinning enough to be pourable. The higher volatility of Naptha works better.. But you must always have a well ventilated or open air space to work with Naptha. Naptha does not change the hardness, adhesion or durability of the silicone.. some other things will.
Whqt are.type 1 and 2 marked for as use typically? Where I live I basically only see 2 typee advertised - hygienic silicone (ie. bathroom/kitchen use) and marine silicone. Data sheets for both show only a few percent of solvents though.
Why did You not show us what happened to the mixture? You did not pour it into a mould? You did not take an item out of a mould? We don’t even know how this acts when it dries? Or if it dries? Very poor video!😡
If you didn’t get what you want out of a video then ask questions, he doesn’t owe you anything it’s free information and I found it extremely useful. Great video.
For the people who gonna try this methods as a mold making, trust me it will not work. I've tried this several times it didn't work. 1. It doesn't self level it. You can thin it out with mineral spirits, but not LIQUID-ish. Yes, you can pour it but the consistency is still thick to be level it. 2. It doesn't cure . When I tried this method first time, I was expected to work as normal silicone mold makers, but it wasn't. The surface dries way faster than inside, mineral spirit gas is trapped and stays liquid type almost forever. I've waited 2 weeks to demold, it was absolute fail. So I tired thinner layer, 5 mm thickness. the result was same. The surface, like 1~2mm is dried out, and rest of liquid silicone is trapped and never dries. Unless you apply very thin layers like 1 mm thickness, it's not gonna work as a normal silicone mold. Never. If you still want to try this, apply it 1 mm thickness every 1 hour. Consistently build up the layer and make it thicker. It might works, but it would be better to buy proper mold making kits for saving time and keep project safe....
Have you tried adding cornstarch to the mixture? Cornstarch improves dry times in the whole solution. Even in the middle thicker parts where air is normally needed to have it dry out. (not taking into account the shrinkage that will occur.)
@@rikdol Starch work as a Putty type molds. I was aiming to perfect pourable silicone because of self leveling also important to my project. When I added starch in it, it wasn't able to 'pour' the silicone. It dries okay but couldn't make a perfect leveled surface. If someone need a Putty types of molds, starch works great. However for someone who looking for pouring type starch doesn't help to pour. That's what I found so far :D
yes, it will. this vid is bad advice. mineral or silicone oil to work, but the product will be very soft after curing. better to just get proper 2k silicone, if you want it to be pourable
I tried thinning silicone to make a mold. Went fine but then over the course of a few days as it dried it shrank a whole bunch. I guess the thinner eventually evaporates and so the total volume reduces. I've read that this has been the case in other comments
@@BamiAndCheese not the way I did it I'm afraid. I have a video on my page where I recorded the whole process, I think it's called "DIY cheap silicone mold' or something like that
i just tried using paint thinner and it never mix with silicone. i put it in a plastic bottle with marbles and shake for minutes nothing happens. lesson learned just use mineral spirit
If you mix silicone with mineral spirits it will shrink. If you want pourable silicone might as well spend the extra money on 2 compound silicone such as Smooth On or other that has an activator agent. It does cost a bit more, but you save on time and wasted material that you try to make it work. Trust me, been there, done that.
Thank you. I plan on mixing clear silicone with mineral spirits ans soaking flower blossoms in it. I will then set the flower out to dry. After the flowers 💐 🌸 are dry, I will glue the flowers onto a piece of wood to make a painting.
The mineral spirits have long evaporated by the time its been cured so fire will definitely not be a problem ;) aside from this, the heat from resin isn’t enough to reach ignition point of mineral spirits so you’re pretty safe
Hey guys, does any one know how to thin 2-part silicone? I have addition cure Silicone and I wish to reduce the viscosity to make it pourable. Any help is highly appreciated. Thanks
I use Naptha, but I don't think you can find it anymore. When I am out of what I have I will have to find an alternative. That is why I am hoping that the minerals spirits works. But I haven't tried it yet. Good luck
if anything, use mineral or silicone oil. mineral spirits are volatile and WILL evaporate, resulting in the piece shriveling up over time. and even then the result will be very soft and fragile. so this vid isnt the greatest advice. pro tip: to use caulking silicone for moldmaking, mix in a few drops of 75% glycerine. it will cause the silicone to cure all the way through in a few hours. add silicone oil to get a softer end product
it is possible to create a cheap mold of silicone acetic cure and to thin the silicone use acetone 100% nail polish remover in a 4 acetone to 1 silicone ratio, it would not have bubbles, but beware the silicone will not be pourable as the water, it will be more like flowable gel.
I have read that nail polish remover contains oils to prevent drying your (skin?? Nails??). I'd buy my acetone at a hardware store. Probably a lot cheaper too; have you ever looked at the price of Nail Polish? It's astounding!
I have a puzzle... A few months ago, I took some silicone left over in a small tube and mixed it with nail polish remover. Made it thin enough to soak a crocheted removable cap for a tube. Made a nice hard cap that really keeps its shape and strength. So I decided to repeat that with a different item i wanted to cap. I used some silicone i purchased to waterproof a cat shelter I was making. There was plenty left over so I tried to mix that with the same nailpolish. It absolutely will not mix. I thought perhaps because that silicone can start curing even in water, that the small amount of water in the nail polish was resisting the mix. I got some 100% acetone and it still does the same thing. All I can think of is that there was something really different about the first tube of silicone. But haven't a clue what kind, or even brand it was. Any thoughts?
@@arpitagarwal82 Thank you thank you thank you for your reply!! 8 months later and it is still a problem i need to solve. I will get some acetic cure silicone this weekend and get my other projects finished. Love your help!!!
@@craftychrystal7913 You are welcome. I have done lots of research and experiments on mold making using caulk silicone. Feel free to ask any questions or doubts. If you find many available options for acetic cure caulk silicone and have any confusion, then simply go for acetic cure silicone for glass. It make cost couple of bucks more but will work 100%. If you can tell me which country you are from I can find cheaper online silicone for you. There was a youtube channel with very detailed instructions and experiments about caulk mold making. If you want I can search that channel name and share with you.
Unfortunately, mineral spirits, alcohol, lacquer thinner, and other solvents don't work well for this application. They don't really dissolve the silicone well. You can tell by the length of mixing required to get any results. Even if you mix the hell out of it... it comes out very lumpy... and much of the solvent never does get mixed in. I strongly suggest you invest in a can of Flex Seal instead. Flex Seal is silicone rubber that has been designed as a "self-leveling" low viscosity product. It's also available in a number of colors. I have used it many times... and it works perfect for jobs requiring a flowable silicone.
@Tycondaroga100 Flex Seal or any silicone rubber does not stick to polyethylene plastic. It also doesn't stick to Saran Wrap. Try lining your mold with very thin layer of Saran Wrap then pour in the Flex Seal let it set up and then just pull it right out pull the Saran Wrap off and you're good to go.
im planning to make mermaid tail using this silicon tube but the thing is its to hard whe it dry what else do you think i can ad on to silicon tube to make perfect mermaim tail?
You can buy silicone online that cures to a soft stretchy rubber. Like this stuff. www.brickintheyard.com/products/skin-cast-silicone-ultra-soft-silicone-gel
I would recommend something else. For example look into aquarium grade silicone, that is also skin-safe or nontoxic. Yes, you can use these things. But as others have said, this video's advice leaves a silicone that will shrivel and crack and not dry. If you mix in a few drops of 75% glycerine and a couple teaspoons of corn starch, it'll dry smoother and also more durable. Experiment on test patches first. Always use good silicone product, test patches first. When applying the silicone to the mold, your best bet is to put a thin layer on your scale sheet mold and then a piece of Lycra, so that when the silicone cures it cures to the fabric. This will help when you put it on, to give it more durability and also ease of use. Corn starch makes everything firmer, anything oily or that kind of thing makes it softer. Add both and you get something that dries/cures nice but remains flexible. Add mica pigments if you want to color the silicone or thin and add mica to make silicone paint to apply to the scales once fully cured. Remember to spray something for a mold release. Many use cooking spray or silicone lubricant on to make the silicone piece pop out of the mold easier and make the scale details cleaner. Have fun and let the world know the results!!
Acetone works much better and doesn't shrink, unless you mix it too thin. Problem is, thousands of very small bubbles form from a chemical reaction after it starts curing. Vacuuming wont work. This mix works for cold casting, but not for low temp metal or wax casting. The bubbles expand from the heat. I've been using straight silicone caulk for 40 years, as a bronze sculptor, with perfect results every time. One must, just, do it properly. Michael
Are you sure you're using silicone though? Not all caulk is silicone... And even when it is there is the type that wreaks of vinegar as it cures and RTV silicone.. which has its own distinctive smell. I just wouldn't have thought acetone would work because it's pretty polar compared to all the hydrocarbons I usually see people use. So does the acetone just prevent shrinking by acting as a blowing agent? That is, by causing the final product to be a sort of foam?
Camp fuel works for sure. At first it will turn the silicone chunky almost like busted up jello, keep mixing and it will smooth out. I thin it out and brush it into the detail eliminating the possibility of trapped air. After it has set up I apply a second layer but thicker consistancy and add cut strips of gauze bandage to strengthen the mold. After the gauze has been saturated I let that set up. (adding a loop of string on either side of where your separation cut will be made will also give you something to hang onto when you pull it apart). I then add the last layer of silicone over everything (creating a mold about 1/2 inch thick), then after it has fully cured i cut it open. After the plug has been removed, wash out the mold and dry it good. It's ready for use. (make sure that all layers are made from the same type of silicone, don't mix brands. They won't bond together properly). The mold can also be re-sealed by brushing on a thinned out layer of silicone between the cut lines to help eliminate flashing on your edges of the finished part. Plaster/ hyrdro-cal/ hydro-stone etc. can also be used against the silicone mold to back it for strength if needed. Hope this helps someone.
I have never had success thinning any silicone caulk to a pourable state. I mean to say, I have never seen it cure even after a week, with heat. I have used the cornstarch without thinning it, but never tried it on a pourable liquid caulk, so if that works then I have learned something. However, you cannot pour the liquid caulk once you have added the cornstarch. This really defeats the purpose…right?
@@humblehombre9904 I thinned mine with mineral spirits and added cornstarch. The mineral spirits still didn't make it pourable but it did thin it making for a smoother cast and the cornstarch allowed it to cure faster than if it were just mineral spirits and silicone alone. You don't add much but it does aid in the curing process. I put mine in a ziploc bag and squeezed out. Your humidity levels have a lot to do with it as well. Pending silicone caulk doesn't dry with air it cures with the moisture it takes out of the air. So I found that if I boil water and go into a small room where the pot can steam mine cures faster. That or I'll leave it next to the shower in the bathroom to cure.
seems to me that mineral spirits have oil in it and oil doesn’t really dry obviously if you want to make a mold for something you should leave the pushed object in until it cures of it cures. i am trying to work out a way.
To my knowledge, the best options are mineral spirits/mineral turpentine or naphtha. Other substances may work, but it may take a little trial & error to figure out which ones. :)
It's a mixture of many molecules; namely hydrocarbons with similar molecular weight to kerosene but with much more unsaturated cyclic and aromatic compounds than kero. That's why it burns with a sooty flame and smells quite strong.
Several comments indicate that the method in this vid does not work; the silicone will shrink. This will be a problem in your case as well. Best way to dilute silicone would be silicone oil, but it doesn't get close to liquid and the max. ratio I recommend 2:1 silicone to oil or else it will have a sticky surface.
Question- since using flammable mineral spirits.... in mixing for pourable mold - the mold can not be used for something that might need oven cured or heated - right? I use poly clay for intricate pieces and oven cure at 180 to 200 in oven or toaster oven.
@@DevilKitty3 There's virtually nothing you'll encounter in daily life with an auto-ignition temperature any where near 200 degrees F. The possible danger comes more from the (possible) emission of flammable fumes, and having those fumes encounter a spark from, say, the thermostat which controls the temperature, or a pilot flame in a gas appliance. I have NO idea whether this stuff poses any of those problems. I don't think mineral spirits could cause an actual explosion without very specific (and abnormal) conditions, but I could imagine it catching fire.
Is WHAT the same as lacquer thinner? If you mean acetone or acetic acid, no, neither one is the same, and I don't know of alternative names for any of them. Also, I believe lacquer thinner is more flammable than either.
Laquer thinner is a cocktail of solvents. Typically methanol (or ethanol), toluene (or xylene), and acetone (or MEK or both) in varying proportions. It could also contain isopropyl alcohol, organic carbonates, ethyl acetate, the list goes on... The stuff I have contains methanol, toluene, acetone and MEK. Mineral spirits are also technically a mixture of compounds but they are all closely related in that they are some fraction of petroleum distillate (hydrocarbons) having a boiling point between 140 and 200 degrees C.
@@Physco219 i want to make a never wet spray, with clear sylicon and orderlessness minaral spririts. And bring a cheaper version of never wet spray to the market. Putting it all to an aerosol can might do the trick!
@@Physco219 Newer wet spray could repeal water from any surface. Wood concrete, clothes, shoes, glows and keep it all dry, If you spray the compound on them. The repelling effect of dirt or any liquid is extremely satisfying to watch too! This spray is available on Amazon, and sells good. Its expensive, but this way we can bring down the price and it works!!🤓
@@jojualu1 you don't want it to never dry up but to spray on and dry up so it is hard to tell it is there due to how thin it is but being silicon it is VERY hydroPHOBIC and repels water so it can't wet what you have coated in the silicon, so I am guessing you want to thin this down enough so when it does dry it is hard to tell it was applied due to how thin the layer of water repellent layer you applied ? like having rubber galloshes on that are so thin you can't tell they are boots and just seems like you have nothing on, but it is there being a barrier to the water so that it cant "wet" or bond to your feet, so they look almost like they are turning into metallic or glass coating feet because of how water looks with that thin layer of diffraction that occurs since it is not all acting as one item, (*look into I believe it was Veritasium that coated himself with a hydrophobic nano powder aerogel and then stepped into water which he described it as being more resistant to him like it was thicker or something because the water was trying to force him to float up on it like a bubble lol)
@@ThomasAndersonbsf *My product idea is simple. I have noticed that, if we thin silicon with any paint thinners and apply it on a bag or a boot, it will dry on the surface quickly. Once dry, this helps the surface to be water repellent. So i want to use this idea and design a product that could solve the potential problem of liquid pollutants or the water itself from entering any surface that one would want to protect. For instance, from a rain or a ketchup spill etc. But to execute this product, we will have to find a way to keep the silicon and paint thinner(or oderless mineral spirits) in side a container for a very long time. So i was checking, if an aerosol spray caning method, like they would do to preserve and keep the liquidity of a paint spray can, to achieve this goal.* Thanks
I have been seeing videos on the subject of using silicone for molds. As to making or using a pourable version I was wondering if the Henry silicone roof sealer could be used. It says its 100% silicone and I see it spreads out like paint in the videos.
Possibly. You may want to look at the fine print on the label to see if it says something like "acetic acid is generated while curing" somewhere on it if you use it with mineral spirits. Someone told me that 100% silicone adhesives with that on the label are better for making those types of molds. Either way, be careful to use some sort of mold release agent on the object you're making a mold of or the silicone will just get stuck on it. Hope this helps!
I wasn't using any specific ratio. You can put some in and mix. Keep adding mineral spirits until it is to the consistency you want. I think I ended up doing half and half here.
@@theDiYwizard And the cure is even? Shrinkage? Length of cure? The reason I ask is, when you reduce the silicone, as the mineral spirits evaporate, the silicone will reduce by that amount as well, from a chemical standpoint. You can't lose any mass of the silicone, as it is the evaporation of the solvent that enables the cure.
You are correct on the shrinking, it does shrink while curing. Mineral spirits evaporate relatively quickly but I have not seen any difference in cure time for silicone.
Hey @Lancer525, i found like the ONLY other person whole usee this method on RU-vid, she seem to habe some success. If you attempt can you please let me know how things turned out and maybe post a Im really interested in this process Here go's the link: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Os6F4aTrGBY.html
my application is that I need to make custom silicone rubber straps for some of my scuba diving equipment. I need the straps to be around 1/16" thick, and I need to dye the silicone to custom colors. With this technique, I should be able to level a flat pan and then pour the thinned out, dyed silicone into the pan to the desired depth of 1/16" and then when it cures I will have suitable silicone rubber sheets that I can then slice down to my desired width and length! Thanks so much for this video. This was the part of the process I was missing!
