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7

Prying with a narrow screwdriver is a good start. It appears in the photo that you have a bit of a start at the near edge of the top. This particular seal is a throw-away and you can indeed stab it. Something stronger than a pointed stick should do well enough. A small blade philips screwdriver tapped in then bent outward will distort the top sufficiently ...


7

As I recall there are grades of microcrystalline wax available in different hardnesses and melting temperatures, so do try others. I have always used a moldable base to support detailed work. Pitch mixed with Plaster of Paris is the old reliable method. This can be softened with a propane torch, the work pressed in, and upon cooling - you have firm support ...


6

Disclaimer: I have no first-hand experience with industrial resins (like boat resin), but I used craft resin (like crystal epoxy resin) several times. There are 2 aspects to keep in mind when choosing your resin: The properties of the resin Your own health Material properties For pouring and encasing objects in resin, you usually want a crystal clear ...


5

Lego is ABS, which can have a range of melting points melts up to 200°C*. We should consider the lower end of the range just in case, which is often quoted as 105°C. Your resin shouldn't get that hot but you could test (a similar volume in a mould made of scrap, with one brick inside if you're really worried). Generally, slower epoxies are cooler, and large ...


4

Most household pans work fine for melting lead. Make sure they are thick enough, don't have plastic parts, and don't have Teflon or similar coatings (Teflon and lead share their melting points, apparently). It's best to use a metal handle (I've used those aluminum camping pan grippers in the past, which are very practical, but I only melted relatively small ...


4

The miniature sealed inside implies you want clear resin so you can see the miniature (not a secret miniature that someone would take your word is in there). For this requirement, there really isn't a material you can use to dilute the resin. If the resin could be opaque, you could use a small amount of resin as a binder for a lot of cheap, solid filler. ...


4

There is no other easily available alloy than Copper based ones that are gold colored. Brass is the most readily available that will have a gold color. There is also a very wide variety of bronzes that will let you choose a precise color. But Copper alloys are maybe not the best option have here. It is very heavy. There is a wide variety of option to get ...


4

Maybe you could use epoxy resin instead of metal. It's not exactly cheap and you'd have to do some research as to which resin is best suited for your purpose (or suited at all), but there are tons of YouTube videos of how to design tables with epoxy. The coloration could be a problem because depending on the pigment it won't look like metal at all, even if ...


4

Is this to make a pattern for investment casting? If so, any wax or plastic (with no filler like Fiberglass) can be used. When I worked in the industry they made patterns of paraffin wax and used beeswax blend for attachments. As I remember, they mostly used soldering irons for shaping. The molds were burned out at 1700°F; this may be different in the ...


4

I've used a food grade silicone in the past that has the consistency of pudding. It is rather soft and very weak and would not hold up in the example you provide. I have used a more expensive silicone, also food grade that requires substantial mixing to get good results, often requiring vacuum degassing for smooth surfaces. In your example, I expect that ...


3

I actually did this six months ago, and the shape that I cast is still solid, virtually indestructible and mold-free, so I am speaking from experience here. The instructions I wrote down here for making milk paint are very similar, but with a few notable differences. It is very important that you work in a hygienic and sterile environment, which means ...


3

If you're using a two-part pourable silicone, you can make a mold of the item with a reusable gelatin-glycerin mold material you can make at home. There are a lot of variations on the formula resulting in different characteristics. The material, itself, is also molded into special effects prosthetics instead of using latex rubber. To investigate the ...


3

I agree with #torjek that a separator (mold-release) spray or liquid would make it possible to caste a silicone object with silicone as the mold making material. The benefit of getting good at this technique is that you could then caste replacement silicone earplugs using the mold which you just made out of silicone. If you need more protection for your ...


3

You should not handle toner powder at all without a high quality filter mask and potentially safety glasses. Loose toner is a health risk for the respiratory system due to it's particle size. It's not toxic, but some studies compare it's effects to the fine dust of diesel exhaust or even asbestos. You should at least expect an irritation or even inflammation ...


3

There are various common solvents, like mineral spirits, that will thin silicone. However, the solvent becomes part of the volume. Once the silicone cures, the solvent will leach out and evaporate, and the casting will shrink by the volume of solvent added. This is sometimes done on purpose to make a finished item that's smaller than the mold. However, ...


3

There are still a couple of ambiguities in the description, so I'll try to cover a few variations on what you've described, including a possible alternate approach. Resin casting as the "finished" item The question describes the objective of making a small box, similar to a ring box, that will be lined internally. The scenario I'll describe in ...


3

The terminology varies from "industry" to "industry" but the concepts are the same. I watched years ago a video teaching creation of molds from fiberglass cloth. The original was called a plug, the mold was created from the plug and the part was created from the mold. In jewelry casting, the concept is the same, but the words are ...


3

I would suggest charcoal and no flux. Keep molten time to a minimum. Charcoal is used on molten lead for long periods to reduce oxidation. For many copper alloys , hydrogen absorption is a problem ; it evolves during freezing causing porosity. I read in ASM Metals Handbook that molten silver may absorbs oxygen causing porosity. Charcoal should provide some ...


3

Casting foam inlays isn't all that different from creating a silicone mold, except the mold is mostly pressure-sealed; the foam creates a lot of pressure, so the mold needs to be strong enough to handle it. The foam is related to Gorilla Glue, so it takes meticulous prep and plenty of mold release everywhere if you want to be able to take the mold apart ...


3

There are other resins (mostly 2 part epoxy resins) that can be food safe. Can be means that : It has to say "food safe" on the packaging, and You have to measure the components and mix them very pecisely. 2 Component resins bring all the chemicals needed to harden, only they are seperated in the 2 components. The components themselves are ...


3

You can find many epoxies and some other resins that are certified food safe. Casting resins are often used for items that will be in contact with the body or food. The US and EU (and I assume other countries), have standards for certifying the materials as safe for these purposes. There are actually several parts to the answer. Certain kinds of plastics ...


3

Use a clear two part epoxy resin to fill the gouges. You can get one with a short drying time (5 minute epoxy) at most hardware stores or even the dollar store. Ensure if its a two part mold, not to put the parts together while its drying or they will stick together. Apply the glue in a ventilated area.


3

A hair dryer is actually a bad way to deal with bubbles. It blows too much air, too little heat, and can blow dust onto the resin. Start by minimizing bubbles There are many techniques to minimize bubbles in the first place. That would really be a good subject for a separate question, so I won't get into that tangent here. But that's the first step --...


2

There are ovens made to be opened when hot and there are ovens not made to be opened when hot. From what you mention what the manual says, yours can not be opened when hot. As there are different parts that go wrong at strong heat loss or getting the full blast of the oven heat, it is impossible to predict what your oven can handle and whether you can adjust ...


2

By "cast," think they are trying to say mold. The beginning technology would be silica sand with a binder. Silica is common beige beach or "play" sand; the binder could be water (damp sand), but will have no strength when it dries. I am thinking something like white wood glue diluted with water. Or, look up "how to make a simple sand ...


2

It depends: What is your mold material ? I expect any type of glass would fuse to any ceramic mold materials I am familiar with ( mostly alumina). And many glasses get soft and bendable at 1500 F , but that is nowhere near liquid which will be 2200+ F. How hot can you get your melting furnace? High alloy stainless ( 310 = 25 Cr : 20 Ni) melts "low" and ...


2

Dampening is actually more complicated than what you're asking. It isn't simply a matter of using a material that dampens vibration. It's a function of the frequency you want to dampen. You will dampen some frequencies, but amplify others, and can get resonance that's more problematic than having no damper at all. If the dampers will be supporting weight, ...


2

It looks to me as though the marks you are seeing are resulting from your resin shrinking from the inside out (hottest part first) as it cures, while the resin on the outside (the coolest part) is still somewhat liquid, thus pulling away from the mold and leaving marks due to places where it has still adhered to the mold versus where it has pulled away. So ...


2

For a gold color , with no coating, you are limited to copper alloys. They come in a wide color range from red bronzes to silver "German silver".


2

The reactions you noticed are quite certainly not the silicone, but the by-product/reaction-starter of the hardening silicone, an acid. This acid can usually just escape as vapor and is what makes the acidic smell after using silicone. There are different versions of home construction silicone, that use different chemical pathways for hardening and therefore ...


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