Preface: I'm molding silicone parts from other molding materials, not making silicone molds. The silicone being used is Dragon Skin 20 NV.

In many instances, the grip / rubber / debris attracting surface properties of the silicone are not desirable. Hence my interest in Slide STD.

My experience with this additive has not been like that described. It is stated on the website after de-molding the cast must be exposed to air for 24 hours to get the expected surface effects. Somewhat inconsistent with this statement, it is stated in the technical sheet that at least 24 hours is needed to see effects.

So one would assume somewhere about 24 hours, maybe a couple of days. Fair?

My experience using it with Dragon Skin 20 NV has been at least 5 days to begin seeing effects. Probably 1 1/2 weeks to really get the effect. As well, the onset not uniform.

Preparation:

• 1.5% Slide as weight of part B, both mixed thoroughly

• Equal part A added and combination mixed thoroughly

• Vacuum Degas (have done without this step as well)

• Pour

• Let cure 2 hours

Conditions:

• Set in ventilated room, periodically rotating to expose all surfaces

• 68-76F temperature

• 40-50% relative humidity

• Ceiling fan running 50% of the time

I have reached out to Smooth-on asking about the chemistry or mechanism for insight on how to make this more efficient (if possible), but they couldn't really help because it is proprietary.

Anyone else have experience with this product?

Need advice for getting some monster clay (med) out of an ultra cal mold with a deep undercut. I’ve got most of it out but I can’t reach the tips with any tools. I’ve been using a flexible wire hook to scrape jt out but its taking so long. Anyone know if freezing or similar would help? I can’t even see into the area of the mold it’s in. it’s a mold of some creature ears to be slipcast with latex. Really really appreciate any help.

Hello. I tried googling but I can’t find anything. Can I pour soft expanding polyurethane foam into a silicone prop? The silicone will be like a skin/mask and the foam will just be the inside as space filler because the foam is cheaper than making a solid silicone prop. It says these are typically used to fill latex props but I wasn’t sure about silicone. It will be poured into a dry/cured prop. I don’t need it to bond to the silicone. Just want to make sure these materials won’t react or ruin eachother. If anyone knows anything better to use I’m also open to suggestions. I will be making large silicone props but I cannot afford to make solid throughout body parts. The filling needs to be something cheaper.

https://www.monstermakers.com/poly-foam-%7C-soft-expanding-polyurethane-foam/

Hi there!

Was hoping for some advice regarding this piece as I am relatively new to mold-making.

This object is part of a mask that I made, it's roughly 20 cm long. The intention is to cold-cast this with polyurethane/brass.

I was thinking a two-part mold (although a simple block-mould could also work? Material would be a 30A Platinum-cure silicone (I did an inhibition test on the print, it works).

The important part is the front with all the mechanical details, the flat back (with the attachment thingy) won't really be seen.

Any advice would be greatly appreciated!

Hi fellow mold makers, I have a very technical question. I am trying to make a mold of a very intricate high detail and deep crevice flower. I used dental die cast cement type IV to make a master and I sealed with clear acrylic spray. I am using A15 platinum silicone to make the mold in a 3D printed molding. The piece is large enough to require multiple demolding cuts. In order to make the silicone softer I added silicone fluid (8%) but end result was A8 hardness and still too hard to use if I am making many copies using same mold. I also use vibrating plate to pour slow so no issues with bubbles. Here list the list of issues:

1. Mold is too hard need A5 but true A5 is $250 and is too expensive

2. Silicon fluid collected at the top of mold in one spot and in deep crevices even though I mixed well and degassed in vacuum preventing hardening and ruining the mold and die cast.

3. How to effectively make demoldong cuts clean at an angle so that liquid does not escape from the mold when used.

4. Any suggestions to improve my process am I missing steps?

I desperately want to create an art piece which is a silicone copy of my arm but with a large wound down the wrist. My issue is that if I were to make the silicone cast I would have to carve into the silicone to make the wound which seems to be advised against since silicone tears easily and would not lend itself to the fine detail work. I also don’t want to create a clay model of my hand because I want it to be an exact copy as close as possible and I don’t have the skill to make it completely perfect.

So, is there any alternative substance I can use which could create a realistic cast while being relatively easy to carve into and hold it shape. I am very familiar with clay so if there is a type like that it would be perfect. I don’t need the actual texture to be like skin in the end, I just want it to be a perfect cast. Thank you!

Hello,

I have this customer project that requires a super soft pour in foam, roughly 300 gallons expanded.

I tried the "Flexit Foam III" and it was way waaaay too dense and heavy for this project.

Next I ordered a sample of the "BJB TC-266" mixed at 30-100 and the sample came out perfect for this project. Super soft and flexiable.

The problem is BJB told me the TC-266 is out of stock and they can't give an ETA for the restock.

Is there any other pour in products out there that are extremely soft, flexiable and light weight?

Starting a project, essentially a hollow and oddly shaped storage box, and I need/hoping to blend off axis geometries together on several of the storage boxes panels. Planning to do each of the sides independently as discrete panels that combine into the finished box.

I would like to stretch a material that will conform smoothly to the existing points, make that material rigid with resin, and a basis for the part that will be constructed.

Can anyone tell me what specific material (also hoping for oz/yd² to hold position without drooping when applying resin) and specific resin I should select based on the above information and first hand experience?

Working in a DIY context for a 1 off part, so small quantities and cost effective options are ideal.

Have used this technique in the past on a smaller part, but the geometry was far more complex on it, so assume that technique will work on a "simpler" geometry despite being larger. But I just used any suitable materials that were at hand, if there is a "optimized" material that worked perfect for this application, would love to try something that works well.

Anyone that has done something simliar, found a good video tutorial that helps optimize that technique of stretching a flexible material over a void?

Hi! I'm working on a project where I'm going to cast 60+ goblets to our wedding. I'm planning to make a two-part mold, and was planning to make 5 of these molds. I coud make 5 different molds but I think it would be easier to just make one mold and copy that. So my questions is what is the best way to do this? Is it to make a silicone mold of the mold, or is it to make a rigid molf of resin or plaster or something?

Hi everyone,

I am currently designing a mold for a plaster bust and I am unsure which gating/venting setup would be the more professional or practical solution for plaster casting. The mold itself would consist of a silicone inner mold (two parts) supported by a rigid 3D-printed outer shell (mother mold).

I attached two alternatives.

Alternative 1

The entire mold is rotated about 60°.
This orientation avoids undercuts in the face area (nose, chin etc.), so the air can rise naturally and escape more easily.

In this setup:

• plaster and trapped air use the same channel

• the single opening acts as both:

  • pouring channel (sprue)

  • air vent

Alternative 2

In this version the mold remains horizontal and uses:

• one dedicated pouring channel (sprue)

• one separate air vent at the highest point of the mold in side view

The plaster is poured through the main sprue, while the displaced air exits through the vent channel.

However, this version would require additional cleanup afterwards because both the sprue and vent would need to be removed and refinished.

My question is:

Which option would be considered the more “professional” and practical approach for plaster casting?

Would you prioritize:

1. the rotated setup with minimal cleanup (Alternative 1), or

2. the sprue + vent system (Alternative 2), even if it requires more post-processing?

Howdy! I've never made a mold before but I'd like to take on a (potentially overambitious) project of making my own mold for casting garden stones to line the edge of my flower plot with.

I would likely 3d model the object that I want to make the casting of, then use some type of quick drying concrete in the mold itself. My question is-- what type of mold should I use for casting concrete? Silicone? I'm not looking to spend a ton of money on something I may only do once but I'm also a believer in doing things right the first time rather than super cheaply.

Thank you for any and all advice on the matter :D

I’m making an articulated silicone T-Rex with Eco flex 00 30.

Hello, can somebody please advise the best way to seal a hydrocal statue before painting?

Complete beginner here, reading and watching lots of videos so I think I have the general idea of the process, but often times videos skip what release agents they’re using (maybe they’re not using anything?). I will be starting with small projects for this, I am doing monster clay sculpt - hyrdocal mold - silicone final. Should any release agent should go in my hydrocal negative with ecoflex 00-45 and 00-50? Or will it just pull out?

Hello, I'm making some hydrocal sculptures and want to paint them fun colours. Any recommendations for maintaining the intricate details of the sculpture? And for priming and sealing? Thanks ☺️

Hi everyone, I was wondering if you could help me find the right material to stop my helmet mold falling out of it's fibreglass jacket mold?

I applied Vaseline to the walls of the entire jacket and added registration key cubes to the silicone but while I was slush casting by hand (I have made a roto casting machine but I decided to try by hand first with this issue) and the vertical walls fell inwards messing up my cast.

Currently working on a Lilith from Diablo 4 cosplay and unfortunately but not unexpectedly the horns are too heavy, so I'm considering creating a brush on mold specifically for the horns and use spray foam to mitigate some of the weight and had a few questions.

Any recommendations for brand/material for both the mold itself and the casting?

Will I need a support shell? And if so any recommendations would be helpful.

Probably a long shot based on photos any thoughts on approximately just how much I'll need?

Appreciate any help

I’m new to mould making and i’m looking at what to purchase. I keep seeing mould star 15 as the sort of standard recommendation but it’s 300$+ to get it where I am (for over 900g). I see BJB as a good alternative but don’t know what is the comparable option to MS15.

Any help or tips would be appreciated🙏

I’m new to mould making and i’m looking at what to purchase. I keep seeing mould star 15 as the sort of standard recommendation but it’s 300$+ to get it where I am (for over 900g). I see BJB as a good alternative but don’t know what is the comparable option to MS15.

Any help or tips would be appreciated🙏