Silicone mold casting

silicone mold casting

 

Five tips for casting resin in silicone molds

by Tania of House of Molds

1. Wear gloves when handling molds and pouring resin.  Not only do they keep you safe from resin, but they also prevent fingerprints inside the molds.  Sometimes these fingerprints can show up on your resin castings.  Note:  The more glossy the mold surface, the easier it is to leave a visible fingerprint on the mold.

2.  Be sure your mold is clean before casting.  You do not want any dust or resin from a previous casting inside the cavity.  These will cast onto your piece.

3.  Take care when positioning your mold.  If your casting table has a rough surface or a non level top, your resin piece could be uneven, despite using a perfect mold and top quality resin.  You can best prepare a crafting surface for your molds by using a bubble level to check your table levelness.

4.  Do not overfill the mold, as to prevent a lot of excess sanding once your piece is finished.  In case of resin voids, you can make a second resin pouring anytime by following these rules

*make it when your resin is still at gel stage

*Use the same brand of resin

*pour the next layer before demolding

5.  For help when demolding, gently press the mold then add a drop of soapy water inside.  Press again and push the object out from the bottom of the mold.  This will make resin extraction from the mold easy and quick.

What other questions do you have about silicone mold casting?

Like this post? You may be interested in  How to make resin crystals

19 Comments

Jim Wilson

Hi, I would like a teardrop shaped mold to produce a pendant.
I wish to embed a piece of exotic wood in the teardrop.
How can I make or find a mold that will not have a seam as when 2 halves are joined?

Do you have such a mold I can buy?
Thanks
Jim

Reply
Jim Wilson

Hi Katherine;
A 3D teardrop would be first choice.

I see how a flat backed pendant could be a one piece mold, easier for pouring?

Will a wooden artifact float in the resin, or stay where it is placed?

Thanks
Jim

Reply
Jackie

Since it appears that no one here fully answered you Jim;
A 3D is possible – you will need to do some work to remove the sprue or funnel mark after curing for this option.
A flat back is always easier (really think about how you want the piece to sit…if it’s really a full teardrop, it will stand up off the chest a bit and tend to turn or roll to the side…do your inclusions or what have you that you plan to use in the pendant make that a thing that you actually want?) Flats are easier in almost every respect in my experience…
Any artifact (assuming proper sealing whatever it is) can either sit or float depending on your technique while casting) People tend to grossly underestimate the sheet amount of planning that resin takes IMO. I have a full set up for vacuum and have actually cast (including mold making) WAY less that I wanted to as well as way more than I wanted to. I believe the amount of research, trial and error and supplies for doing all of the above are the reason most non-industrial makers either hold onto some strategic info and other quality effecting ‘secrets’ – even on blogs such as this one.
Hope this info helps you plan your resin-making moves!

Reply
Ronald Ainaire

That depends on the weight of the wood. I find it best to weight the pc of wood down. use a toothpick with some weight on the outside of the mold.

Reply
Jackie

I disagree ‘mostly’ with the above statement. IF actual weight was an issue for any inclusion (attributing proper sealing of course) a caster would simply use a layered pouring method over weighing something down…I can understand the concept as a concept but can’t think of anything that would make that ‘technique’ preferable. When one says you ‘can’ do a thing it doesn’t technically mean that it is what you ‘should do’ in a particular situation for a particular effect.
Resin is one of the few mediums that I have worked in that I hesitate to just work with any info that isn’t at least a paragraph long with explanations such as this since so many factors affect the end results. At least that’s my experience and opinion – this isn’t my website tho…:) happy casting!

Reply
Fran Hayworth

Could you tell me where I can buy silicone molds for resin jewellery (bracelet in particular) in South Africa?

Reply
Galen

I had a very difficult time getting a pendant out of a silicon tubular mold. Is there an easy way to get the pice out? The mold was a half inch in diameter and 2 inches long. I embedded some Austrian crystals and its was beautiful but getting it out was incredibly tough and it broke leaving half inside. I ended up flipping the mold inside out but now have fingerprints inside. How do I get those out?

Reply
Katherine Swift

Sometimes it will work where you can introduce a drop of dish soap in between the casting and the mold to help you get it out. Try some denatured alcohol to remove the fingerprints.

Reply
Laska

Hello..i am searching forum those beautifull silver end with rings on it…to adjust to a necklace . Where van i buy those??

Reply
Ashley

What is the best way to insert a finding when using a mold? Particularly the screw in one? I would think it would be hard to get it to stay standing straight if you put it in before the resin cured

Reply
Katherine Swift

I’m not sure I understand your question. You want to insert a screw in a resin mold?

Reply
Jackie

The only sure way is to layer the area of inclusion so that the finding is either gravity held or holds on it’s own or with slight help in the first pour and then is partially cast in place for the second pour. I would think that the type of finding and the location in relation to the liquid resin (including if the resin will have any flat side or part-line) would dictate which method is best in your particular project. Of course this is not my site so I offer info simply a a fellow caster wanting to try to be helpful. Happy casting!

Reply
Tamara Morrissette

hi Katherine, I’m having an issue with the molds. I find the cured resin piece is beautiful and shiny on the top, but everywhere the resin touches the mold, it is cloudy and not smooth.

Reply
Katherine Swift

Hi Tamara, it sounds like the template that was used to make your model was not shiny. If it wasn’t shiny, the surface of subsequent castings won’t be either.

Reply
Jackie

OR…there is something impeding the shine. The surface tension of the original SHOULD provide the shine naturally as Katherine notes above…this is a huge part of why resin works for us…but everything from improper mold making to a release agent inappropriate to preserving contact shine CAN interfere. This is not my web site and I offer my opinion only as a fellow caster courtesy. Happy Casting!

Reply
Renee

Hi there,
I have 2 questions regarding the Italian clear silicone molds you sell on the site:
1) Are they made so that you’re resin casting come out crystal clear (provided you followed procedures properly)?
And 2) do you need a releasing agent, and if so they recommend one that has natural wax base. Do you carry a releasing agent fitting that description and if not do you know where we can find a good one and what it’s called?

Thanks!

Reply

Leave a Reply

Your email address will not be published. Required fields are marked *

*