From various plumbing repairs, I am in possession of a few tubes of silicone caulk. With how this material dries, I was wondering if it is possible to use this stuff as mold making or casting material for custom toy projects. And if so, what advice and or precautions do I need to proceed?
>>5589286
It's possible in the most basic fashion, but you'd be foolish to waste your time.
Silicone caulk and casting silicone are of different viscosities. The Silicone caulk would layer as you pile it in and trap bubbles, making for near worthless molds. Conversely, proper mold making silicone would instead come out as a thin poured stream that would build up gradually and in a controlled fashion, reducing bubbles almost entirely.
were you gonna make a dick out of it?
you could make decoden lol
http://matrixarmory.blogspot.com/2012/01/mold-making-cheap-and-easy.html?
I tried the above guide once. It basically involves applying a thin layer of caulk at a time. Trying to minimize the bubbles is a challenge.
Another method I saw on google was to thin the caulk in vinegar (acetic acid) and make it pourable. Remember reading it takes an extra long time to dry.
Generally what >>5589324 says but it's still good for that one-off mold if you don't maintain a set of molding/casting supplies.
>>5589286
Yes, it's possible and the results can produce some very decent one-off or short run molds.
An important addition is a few drops of liquid glycerin which you can pick up at any pharmacy. Silicone caulking cures by absorbing moisture so the silicone caulk will generally surface cure or "skin over" first due to the exposure to the moisture in the air, and this will inhibit thorough curing.
A characteristic of glycerin is that it's hygroscopic, so mixing in glyercin allows moisture to penetrate deeply into the silicone caulk allowing for a thorough and faster cure.
Add a little non-white acrylic paint. The acrylic paint gives you an indicator as to how well you've mixed your batch. Mix until you get a consistent color.
Corn starch can be used to thicken and strengthen the silicone mold--- particularly useful if you want to make a push mold.
Since we've got this topic - I was thinking of using silicon caulk mixed with talc powder to make casts of stuff like figma hair parts. I heard the final piece holds detail well and remains pliable. Anyone tried something similar before?
>>5590413
The actual part, I mean, not the mold.
>>5590416
>>5590413
Not sure about the part itself and I personally have not done this myself yet, but many diy sites mention how to use silicone caulk for making molds very cheaply. I seen three ways, first way is removing the retarder from the caulk using a lot of water, very very messy and unnecessary imo. Second way is a few drops of glycerine, not sure the exact reaction the glycerine is having to make this work but it seems to work.
Third way is equal parts caulk and corn starch. The corn starch distributes moisture evenly throughout the silicone speeding up the curing. Talc powder I seen mentioned once or twice as an alternative to people who don't like the idea of mixing silicone with a product like corn starch out of fear of any possible degrading. I have never heard of wether or not degrading is faste or slower using one over the other. All I know is the point of the talc is to cure the silicone faster without having uncared bits in the middle.
>>5589286
In the past, there were threads on /tg/ showing how to use various easily-acquired materials to make molds for wargaming miniatures. They might be able to help.
>>5590519
Second way is a few drops of glycerine, not sure the exact reaction the glycerine is having to make this work but it seems to work.
Already explained in >>>5590253
Glyercin is hygroscopic (absorbs moisture), so mixing glycerin thoroughly with the silicone caulk allows moisture to be distributed throughout the silicone for a faster, thorough cure. Basically, it performs the same role as corn starch but allows you to retain a higher viscosity if required.
>>5590413
>I was thinking of using silicon caulk mixed with talc powder to make casts of stuff like figma hair parts.
The issue with improvised silicone caulk molds or as an improvised casting medium is the variable shrinkage. Although silicone caulk products boast little to no shrinkage on the label, that's only in the context of original intended application. Some people who've made improved silicone caulk molds have posted that they observed no shrinkage, while others have seen small to substantial shrinkage.
It may also take a variable amount of time for any shrinkage to occur. The part may be fine for days or a few weeks after curing, but may end up shrinking after a few months.
But given how inexpensive the ingredients are, I think it's still worth a shot. Keep track of your ingredient proportions by weight or volume so you can develop a recipe.
>>5590592
>Some people who've made improved silicone caulk molds
I meant *improvised* silicone caulk molds...
I watched a lot of videos on the youtube where people simply soaked the silicon caulk in very soapy water to make it not adhere to things, then clump it up to use it like mold putty
>>5591828
Which recipe you use depends on your needs.
The glycerin and corn starch recipe allows you to adjust the consistency of the silicone caulk and you have a longer working time, which has advantages--- like having the time to really work it into high detail areas and minor undercuts. The soapy water and silicone caulk has a putty-like consistency and a fast set-up time so there are some limitations that go along with that.
Silicone caulk will adhere to itself, so you could combine the two methods. Work the glycerin/silicone mixture into high detail areas and minor undercuts, wait for it to cure, then use the soap/silicone putty to create the mother mold.
