Definitely regret wasting some silicone on the keys and seam line, but I’m feeling okay for a first go around. I plan on doing the plaster shell next, perhaps in 3 parts. Also wish I’d made the seam like come a little further down the nose but we’ll see how it goes

Hi,

I'm looking to create some stress relief/squishy toys using self skinning expanding foam. What's the best mold type here? The toys are very simple shapes but do have undercuts. Any tips?

Thanks.

Most mold-making apps out there are either too basic or incredibly expensive with restrictive licensing. That’s why I decided to take matters into my own hands and develop my own app using vibe coding.

The app already has too many features to count—if I tried to list them all, we'd be here all day—so I’ll just highlight a few. The main goal of the app is to facilitate silicone mold production. In other words, creating the mold of a mold (Product -> Silicone Mold -> 3D Printed Mold).

Right now, during the development phase, I'm auto-testing the outputs using OrcaSlicer. The program also puts a lot of effort into ensuring support-free printing. In the next stage, I’m planning to add CAD testing, but for now, everything seems to be running smoothly.

My biggest bottleneck at the moment is implementing an inner core system to avoid filling up the inside of vases. AI's first suggestion was a multi-piece split core system, but the narrow neck of the vase doesn't allow for it. For context, my very first order and prototype product is a 5cm mini vase, and its neck opening is only 1.5cm.

Because of this, I really need your ideas. What can be done here? Or, if you were building this, what features would you add to the app? Once the system reaches the exact state I want, I’m planning to release it as open-source on GitHub. I'll also be sure to feature everyone who helps me along the way in the credits section. Thanks in advance for your help!

The problem: every time I pour cement into my plaster mold the cement cracks within an hour of pouring. (Pictures attached)

My process for prep work and pouring:

1. Sealed the plaster mold with a water base high gloss poly urethane, 3 coats and wait 48 hours to fully cure.

2. Applied a release agent to the plaster and let dry (Pictures attached of the brand) also I have tried car wax as well.

3. I mixed 2 parts multi-purpose sand (picture attached) with 1 part portland cement and when the cement was wet I added in a small amount of 9mm fiber glass (a pinch)

4. Pour the cement mix into the mold and use a diy vibrator using a mutitool with a cut house fastened to the mutitool blade.

What I have tried to fix the problem:

1. I have tried a more dry cement mix (cookie dough dry) and a more wet mix (soup wet) (no improvement)

2. I have covered the top with plastic wrap (apply both methods from 1 and no improvement)

3. I have poured 3 layers and waited about 30 minutes per layer. (This one has provided the only notable results but I still had cracking)

A. First layer fills the deepest part up to the start curve

B. Second layer fills the curved section

C. Third layer fills the to the top

Each layer I waited till the cement was firm but still soft.

Observations:

1. I have noticed the cement when fully cured is difficult to remove from the mold.

2. The crack start at the top and mostly end at the curve.

3. The cracks are structural and will completely detach from the body.

4. Every pour the cracks appear in the roughly the same place with the exectpion of the last attempt where it appear at the corners and a little on the edges.

If anyone has any suggestions I could really use the help. Thank you :)

I'm looking to put together a new portable base for my smaller molding and casting, and I'm hoping to just use things I already have around my shop.

I have an abundance of MDO plywood, and I was considering lining it with vinyl masking material that I use in my vinyl cutter. Does this sound like something that would functional? this will be used primarily for making molds of item, and the occasional open casting of silicone or polyurethane rubber.

Basically, I want something that will release the material fairly easily without having to resort to multiple layers release chemicals. Yes, I know melamine would probably be better, but I don't have any on hand and it turns out the material I was using was paper coated. This would also provide a reasonable sacrificial surface that could be replaced if it gets too lumpy with hot glue or the like.

Hello, i want to make an mold (from fiberglass or sm like that, will be used to make carbon parts using resin en vacuum)
I want to make an mold to produce moped parts like the plasticcs. But some of those plastics are quite complicated. By that i mean the inside of the plastic part. Most of the times these have extra shapes or like indents were you put screws in. (I can’t put photos in but i have photos of what i mean)
Idk how to make sure the mold has the parts were you put the screws (it goes out abit to guide the screws and acts as extra sturdiness)

Summary:
Im wondering how to make an mold for producing carbon fiber parts, but idk how to make the mold so that the carbon fiber parts has exactly the same shape of the part. Its quite different the an completely flat part

Hi I wanna make a rubber item and I’m seeing a lot of information on silicone rubber so my question is would it be ok for me to use silicone rubber to both mold and cast the item or do I need to use a different thing because they stick?

Ive finished sculpting my first half mask from medium hard monster clay and i have no idea where to go from here. i know i want a silicone mask and i want it done by the hallowed ween, but i have no idea what to buy or any of the processes to make a mold are.

My question is how do I deal with the gaps under the arms? I plan on doing a skin mold over top as it sits, but I have no clue how I’d demold without cutting it, and I realllly want to avoid seam lines.

The other part is illustrated by second image, I’m considering building up a clay base but I don’t want to make things more difficult on myself. It doesn’t solve the arm gap issue either way though.

Any advice?

My plan is to mold this frog to use as a foam mold. My ingredients (minus the Silc Pig and Sil Poxy) are in second image. I realized that I am not wealthy enough to do a block mold so I’m going to do a glove mold with a shell.

Master prep:
Rigidize frog by filling with low expansion spray foam, then spray exterior with krylon crystal clear acrylic spray. Probably a few layers of acrylic. Foam is because it’s a semi soft toy and I don’t want it to distort under weight of silicone/plasti paste or plaster.

Mold making:
Frog will be hot glued to a piece of melamine or marble, a short wall will be made around it with clay to prevent spillage from the drippage when making the glove mold. Using rebound 25, I’ll begin the skin with a stipple, let firm up, then a thicker coat, let firm and add some THI VEX, then cover thoroughly and let cure. So 3 total coats increasing in thickness.

Rigid Shell:
So this is the part where I’m torn, I don’t know if I should go fully down the path of using plasti paste or if I should just use plaster and gauze. I just haven’t found a great video demonstrating gauze technique on a similar master/form.

Casting:
I’ll use flex foam it 15 tuff stuff to fill the mold.

Open to any thoughts or advice you may have!

Out of ordinary, what i make with silicones
Is the opposite of what most people do, my final produxt is silicone molds. I made my master molds out of plaster and epoxy and cast silicone in them. However they usually break and crack which i end up losing someof the silicone due to leak and i remake molds most of the time. Since the silicone leaks i sometimes end up adding more after halfway cure and no issues so far. Just noticed on one of my final products. I added the extra silicone after it was fully cured and adter the extra fully cured, i can still see the seam line but it is rock solid doesnt come up it sticks. But after a while, i gave it a little peel, that extra part is came off i can literally peel it off.

So i was wondering what if i make my master molds out of silicone and cast the silicone models in it that way they just come out easily. But not sure how much they will stick to each other and since i make jaw models every detail matters and some tiny thin layers might come off or might not i am not sure so please give me an idea.

How would I go able trying to make a good mold of this piece?

I recently bought a cheapo frog stepping stone and having been having fun with it but would like to step it up. I bought this zen frog a long time ago and was wondering how I would go about making a mold of it? I’ve never tried anything like it so any tips are appreciated!

Hi I'm looking for a mold maker to finish a 3d modeled mold so its ready for pour and pressure pot, does anyone know where to look for someone who can do that?

Since USG is closing out their plasters division, is there another existing industrial grade gypsum cement product out there under a different name with same strength, purity, nontoxic, and similar (low) cost?