For a mold that will cast 5 or 6 pieces? what is the difference between hydrocal and plaster of Paris. We have shared tips and ideas that you can refer to. You can heat ultracal, but you need to follow heating instructions. Take note that variations in the temperatures of the slurry affect the setting time, so you must keep water and hydrocal at a stable temperature before using. Hydrocal and ultracal are gypsum cement and both have different properties. You can check out the article for useful tips and ideas that you can refer to when working with plaster of Paris. Hydrocal is a bit expensive, but worth the cost, for water-proof, or rugged hands-on scenery. Of course, you want to immediately figure out what causes discoloration Building a house is rock solid. I dont' think that is my approach. When hardened, it will permit removal of molds with "undercuts" whereas plaster of paris will break off detail. This is the plaster that is used for skim coating blue board. Avoid using water that is treated. . You know the jagged parts of, the mold that will stick out. I would be interested in others experience with hydrocal. Hydrocal sets-up to rock-hardness, and in many cases, will support a person leaning on it to reach distant tracks. Let it soak for one to two minutes. It costs me about Cdn$19/bag, and I am on my third already doing hardshell. Hydrocal is my preference for molded outcrops, since it is tough. Smooth out any bubbles that you can find using a skim coat of a watery mixture once it has completely dried. Hydrocal vs. Plaster of Paris 50312 views. Break down hardened plaster on your working space and clean the area using soap and water. Like Jeff, I also userigid closed cell insulation for cast forms. Login, or register today to interact in our online community, comment on articles, receive our newsletter,
The powdered dye is added to the dry plaster to approximate end color of choice. Another advantage is that is can be cleaned up in the sink. With the base foam (carved for hills and valleys) and the Gypsolite, I only use plaster cloth to bridge over open areas or to merge in the foam with rock castings. What is plaster of Paris? In some instances, the glue will float on top of the water. Thanks, Rich. It is easy to do especially when you are working with small batches. a 10 pound box of this hydrocal was I think 10 bucks..so 1 dollar a pound. For life-casting, alginate (seaweed-based gelatin) is used for a (negative) mold, and plaster is used as the positive casting material. Description. Repair your plaster walls with this DAP 25 lbs. Tap the bottom of the mold to help remove bubbles on the mixture. Take note that there is a difference between the setup time and the curing time. It is enough that Jesus died and that he died for me. This is to make sure that the slurry evenly flows across the surface of the mold. It dries very hard, it shrinks very little and the cast is quite durablebut it takes a while to cure fully,so there is plenty of time for arching correctionsif needed before it's a rock. Just my opinionTim. This website is strictly for entertainment purposes. I will fill coffee cans and place in quart size plastic bags. The average time that it takes for ultracal to set is about 25 to 35 minutes. is this normal? They are all used for casting sculptures and making art objects and molds. Is Hydrocal Better than Plaster of Paris? I am happy with the detail.. and this is the best shot I can show you. I am needing to do some landscaping. Decorating is poetry. The high green strength of the hydrocal reduces breakage during the removal process even from the most complicated latex molds. Both materials are used in different applications like making case molds for slip casting, permanent models, and solid castings. I think Plaster is just fine I have used it before in high school for sculpture projects with no problems. . I have bought the real and the woodlandI mixed them and liked the effect. The longer you take to clean your latex mold.. the harder the plaster becomes.. and the harder to clean.. perhaps even damage to the latex mold when trying to remove the 'left-over'plaster bits. Make sure to break up any lumps that form in the mixture using a spoon. Next, add the plaster of Paris to the water to the water by sifting the powder. I am never going back to any plaster or hydrocal product. It takes an iron man to play with a toy iron horse. If you find you like rock face and stone wall castings, you might also look at Bragdon Enterprises. In the video, how to mix and use ultracal is discussed. We have also shared this article that discusses what hydrocal is made of. Now for my last pic.. just a side note.. but someone out there might want to know. Plaster of Paris is not waterproof. discusses the difference between hydrocal and ultracal, Provides long workability as setting expansion is twice that of molding plaster and pottery plaster, Ideal for both hollow and solid casting lamp bases, moldings, general castings, and figurines, Provides a great value to performance ratio, Requires 45 parts water by weight per 100 parts plaster, Has a stark white color which makes it ideal for accepting colorants. What is hydrocal? I prefer Plaster of Paris because it is easier to drill into to plant trees or otherwise modify. Hydrocal molds can be heated at a maximum temperature of 120 F. Hydrocal dries rock hard, so it is hard to modify or carve. 10 replies. I have tried both. As said, try to locate bulk bagged Hydrocal locate a building supplier that specializes in drywall/ plaster products. The Bragdon foam results in a very light casting, but there's more effort involved than with a plaster casting. Is Hydrocal Better than Plaster of Paris? For the retailer and customer it is easy to spin the big Woodland Scenics rack at the LHS and look no further. All casts must be dried as quickly as possible so that they can develop maximum physical properties. You don't need a lot and it takes forever to put down, so it is cheap per hour of fun. Both have pros and cons so you need to make sure that you weigh out your options to make the best choice based on the project that you are working on. Of course this is the backside.. but its to show you how thin. We have shared an in-depth discussion about the topic. There are ways to overcome this most common is spraying the hydrocal with a mist of wet water before staining. Do not worry much because it will eventually combine into the mixture. What are the main features of hydrocal? You can also check out this article that we have shared titled, what is the difference between hydrocal and plaster of Paris? Ultracal can be used in a wide array of applications. For a head cast you will absolutely want hydrocal. So, the jury is still out on the subject for me. In this article, we will discuss the difference between hydrocal and plaster of Paris. But, Jeffrey, would that not make the plaster essentially impossible to paint? USG Hydrocal White Gypsum Cement is designed for solid and hollow casting and is ideal for giftware and lamp base applications. But all three DEFINITELY have their uses. After sifting the powder, do not start mixing yet. What is the difference between hydrocal and plaster of Paris? Make sure to use plain white glue that is widely available at your local craft store. We have found out that hydrocal is stronger than plaster of Paris and can also take a lot of detail. It is ideal that you wait at least a week. Work with the mixture until you have a smooth and consistent mix. Plaster molds can also be used to cast wax, if the mold is well-soaked beforehand. Video Lifecasting Tutorial: Mixing Hydrocal Plaster. I even took pics to see how much detail there was.. and how easy it was to pull Dental plaster out of the mold. Video Casting Hydrocal White into a Plaster Mold. Add cup of white glue into the water. Step 1: Pour 1 cups of lightweight hydrocal slowly into cup of water. Make sure to touch every corner of the mold especially the ones that like to trap air bubbles. The downside of Hydrocal is that it does not carve or take stains/washes very well. Micro Mark has a very attractively priced Hydrocal offering (compared with WS). We have also shared this article that discusses what hydrocal is made of. I have been using the woodland scenics rolls of plaster cloth and styrofoam and newspaperits going well9 bucks for a rollcan I do it cheaper? So far, it is strong. it seems I go to the hobby shopbuy a crap load of stuffand in about 2 hours im out of supplies! What is the difference with Plaste of paris? Always do your own research before making important decisions. You can use various object to obtain many different rock faces.. to obtain.. a curve.. a gradual incline or what ever. This supplier may also carry masonry supplies. Side note: I can even break this casting a bit.. remove certain areas.. it breaks nicely.. and the plaster cloth on the backholds everything together..so I can go back.. add plaster to the areas.. to seal them up.. and I guess its a mild re-glueing with plaster. Adding glue to the mixture can make the plaster of Paris stronger. Hydrostone are commonly used in tooling and high-quality art object application. My latex molds.. are very flexible.. and would suggest always to keep them out of the sun.. or light for that matter.. Do not pour any leftover plaster of Paris down the drain. I have been using Hydrocal to make rocks out of my Woodland Scenic rubber molds, but it gets expensive after a while. You can use white glue, white flour, or Paris powder as a substitute for plaster. You should use ultracal or hydrocal because they are easy to use, they have a quick setting time, they need less supervision, and they are less prone to shrinkage and cracks. You can also check out this article that we have shared titled, how long does it take for hydrocal to cure? Strictly my O/P as some doe paint hydrocal to seal it first. Cycling. This website is strictly for entertainment purposes. Moreover, they are easy to prepare and can be set after just a few minutes. Always do your own research before making important decisions. I use 2 parts plaster of paris to 1 part water. Hydrocal is multi-purpose gypsum cement that is ideal for both hollow and solid casting sculptures, art objects, and molds. Sets fast in 20-30 minutes without shrinking. This material is specially designed for making thin sections. You cannot paste images directly. again about $4 for a bag of woodland scenics ballast what about just some dirt from outside? It is also more convenient that you clean as you go because it makes the process easier. This is an important step in producing hydrocal that with maximum hardness and strength. Like ultracal and other gypsum material, it is used for casting sculptures for crafts, arts, and other projects. It's natural tendency is to suck up stains or washes etc. Plaster of Paris (USG No. On the other hand, hydrocal is a casting plaster that does an excellent job when it comes to holding detail. The first step is measuring. On the other hand, ultracal is a material that is used for making splash-casting molds and models. Aside from that, hydrocal also takes more detail and does not slough off. However I've heard comments that it is to heavy. Besides.. you might have a 'residue' of 'Pam' or God whatever keeping the paint from really adhering to the casting. We had the "pleasuer" of having Jeff Adam of Motrac Models as a club member. Then I use a paint brush.. and paint the plaster into the fine cracks and detail of the mold. They produce less heat as compared to other products. How do you prepare plaster of Paris? Generally speaking though, I use Sculptamold 50/50 with water when I'm doing rock castings. Of course, you want to immediately figure out what causes discoloration Building a house is rock solid. Hence, you will find fewer shrinkage cracks and your molds and castings will look flawless. For casting of any molds Hydrocal can't be beat. There are various waterproofing agents that you can use which effectively seal the porous surface of the plaster. It would do so after priming. It is specially designed for close-tolerance tooling because of its accuracy, hardness, and flexibility. I have many different moldsfrom homemade to WS and others and I have never had any problems using the p.o.p. The fact of the matter is if one were to make identical castings out of both materials the weight difference is not all that much, both weigh a ton! I believe it helps. Good luck. Also called plaster of Paris, this medium has been used since ancient times to cover walls, ornament buildings, and cast sculptures. plaster should always be added to the water, not water to the plater. Mix them until the glue is thoroughly dissolved in water. I did try adding a little color to one batch and was not as happy with the wayit took washes after that. Make sure that the slurry is carefully poured into the deepest area. Tom View my layout photos! As compared to most plasters, hydrocal is stronger. It is soft, even when cured and is not very strong. These are some of the questions that we will talk about in this article. I wanted its superior strength. Take note that hydrocal has a high green strength which allows it to lessen breakage during removal of the casting from the molds. Leaving the shower curtain open or closed has long been a debate for a lot of people. I don't really recommend trying to cut a master for your own use but Making molds of existing origionals is easily done w/ the RTV. Of course, you want to immediately figure out what causes discoloration Building a house is rock solid. The difference between hydrocal and plaster of Paris is that hydrocal is stronger. Once they have set and are fully fried, they have the best strength. I found plaster cloth a lot cheaper at Michaels, the arts and crafts place. Even though your plaster mix has been mixed correctly with no bubbles.. you can and will still get an impartial filling of the cracks and detail. Generally, the crystals form a structure in the plaster that provides it strength. There are three types of plaster which are the plaster of Paris, lime plaster, and cement plaster. Plaster statues are made from a mix of heat-treated gypsum powder and water that hardens when it dries. I have some really nice molds which give great results with Hydrocal. Yes.. that is the weakest part of a mold.. a thin mold approach that I use. It is the perfect choice for making a solid and hollow casting of figurines, general sculptures, and commercial casts. . One of these days I will try using that same mold with Hydrocal for comparison. Oftentimes, you purchase a material thinking that it is what you need, only to find out later on that it is a different one. Edit (added comment) - Also, I believe that Hydrocal is not particularly keen to take paint. So that makes the P-of-P 66 cents a pound and the H-Lite $4.25 a pound. We have shared an in-depth discussion. I hadn't thought of the scouring of the surface to be redone, but I would expect that to be the method. The difference between hydrocal and ultracal is that ultracal is harder and denser. Both can be used in various art and craft projects. Something I learned real quick about painting plaster of paris. You can also check out this article that we have shared that discusses what the difference is between hydrocal and ultracal. Waterproofing plaster of Paris is important especially if you will use it outdoors. Moreover, how long you mix the slurry will affect the setting time. Stop when the powder is almost covering the surface of the water. No. Well this question intrigued me so today I stopped by Michael's Crafts and picked up an 8# bucket of Plaster of Paris @5.29. can I get this stuff in bulk? Plaster that sloughs off can lead to dusting and chipping. After thoroughly mixing the ingredients, you can proceed to the drying. During the process, it is ground up into a powder form and then heated. The dark gray colors were had by using washes as I mentioned and the red & orange tones were done with artist chalks, then sealed with fixative. They are flexible and can be used for various arts and craft projects. I find Hydrocal is better for making rock castings. Find out how to do this by reading the article that we have shared titled, how to make plaster of Paris stronger. The most commonly used plaster among the three is the Plaster of Paris which is also called gypsum plaster. It can also take a lot of details and does not slough off. I'm in agreement with Walace also. The pictures below are of a Hydrocal High Arched PRR prototype stone viaduct that I've been working on the past week or so. For general wall and ceiling repair. Moreover, the maximum temperature that hydrocal casts are safe from calcination is 120 Fahrenheit. Choose a drying room or oven that offers quick and uniform air circulation. To test if the plaster cast can be safely removed from the mold without deforming it, scratch the surface gently using a metal pin or your fingernail. We have also shared this article that discusses what hydrocal is made of. Shake the bubbles out and level of the castings. I've also used Bragdon Foam with a Bragdon mold. Moreover, ultracal is noncombustible. Check out the rest of the article below for more information. Example: I had poured a tunnel portal using the dental plaster. On the other hand, ultracal and hydrocal do not need the same amount of supervision so it is more convenient to work with. Hydrocal is versatile gypsum cement that is used for hollow and solid castings. We have also shared this article that discusses if perfect cast is the same as plaster of Paris. They can harden and cause the pipes to clog. As a result, the ultracal hardens and slowly becomes hot and highly alkaline. I sprayed the molds with wet water before pouring in the plaster. Hydrocal and ultracal sets quickly. Then apply one more coat of plaster.. followed by one big patch of plaster cloth to the mold.. for added strength. When painting the plaster into the mold.. The answer as to whether or not hydrocal is better than plaster of Paris depends on how you plan to use it. If you are using a 100% silicone caulk mold that is newly made, you need to wait for at least 24 hours before you can use it. You can do this by using a gauze bandage, glass fiber, and other suitable materials. Dilute the detergent by spraying the mold with straight tap water. Here and now, unfortunately, ends my journey on Pixabay, what is the difference between hydrocal and plaster of Paris, discusses if perfect cast is the same as plaster of Paris. Sounds to me like you are buying the WS pre-packaged Hydrocal. Mixing ultracal with water produces a chemical reaction. Leaving the shower curtain open or closed has long been a debate for a lot of people. Easy to make, easy to patch, and don't weigh a ton. The castings can set in about 15 to 20 minutes. While hydrocal is easier to work with when it comes to posting casting projects, ultracal is more durable. They are all used for casting sculptures and making art objects and molds. Light and strong. Aside from that, you can easily purchase them at your local hardware store or even online. This will prevent air bubbles and will also create a uniform and smooth surface. In this article, we have discussed hydrocal, what it is, how to use it, and where to use it. It provides a slightly better heat resistance as compared to pottery plaster with higher dry and wet strengths. Paste as plain text instead, USG Hydrocal Brand White Gypsum Cement is a good multi-purpose product for people looking to upgrade from a standard plaster product to one that has a higher degree of hardness and impact resistance. Choosing a material for a specific project that you are working on can sometimes be confusing because of their similarity. Take note that if you do not properly mix ultracal, the chemical reaction happens faster and it can affect the molds that you are making. Hydrocal is stronger than plaster of Paris. Get all the moisture you can see off the mold. Plaster of paris and cement are about the same price, you just have to buy twice as much for twice the price- even this is usually cheaper than going straight for the quality products. I would not be able to breakit up.. its that strong. On the other hand, it is still a plaster that is heavy, dense, and can shatter when dropped. 1. Yeah, Jeffrey, that makes sense. The patching plastic allows a greater set-up time for the hydrocal and permits better control of forming the scenery profile. It demonstrates mixing tips for white hydrocal. Same can happen with hydrocal but it's far less likely to happen or should I say it will take a little more for it to happen then it will with plaster of Paris. This article discusses if hydrocal is stronger than plaster of Paris. Stir the plaster of Paris and water mixture slowly until it forms an even and smooth consistency. UltraCal-30 is just plain old plaster of paris, with some portland cement, usually in a 8:1 ratio, so you can make your own from a trip to the local hardware store. Otherwise, it can result in severe chemical burns and the person may need to undergo surgery to remove the affected skin tissue. You can also check out this article thatdiscusses if plaster of Paris is flammable. This is a quick shot I took of some under-construction scenery, which is mostly just pink foam covered with Gypsolite with embedded brown paint. I'd stick with the Hydrocal if I were you. Bear in mind that when you pour a large amount of slurry directly on the mold, it results in slight densification of the cast. You see the way the spoon is? Ultracal is just plaster of paris (calcium sulfate Hemihydrate) with portland cement and crystalline silica added. Ultracal is a good choice if your work needs accuracy and a good amount of surface hardness. It shows how to cast shydrocal white into a plaster mold with the use of a fiberglass mat. On the other hand, it is not as durable as compared to ultracal. It usually will only lightly tint. What is the difference between Hydrocal and Ultracal? Hmmmm. How do you prepare hydrocal? Step 3: Add Plaster to the Mixture. The bubbles out and level of the water to the hobby shopbuy a crap load of stuffand about. Pleasuer '' of having Jeff Adam of Motrac models as a substitute for plaster casts. Called plaster of Paris, this medium has been used since ancient times to cover,... 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Redone, but you need to follow heating instructions cement that is for! For cast forms remove bubbles on the other hand, ultracal is a material is! 'Ve also used Bragdon foam results in a very light casting, permanent models, and where to use outdoors... Others and i have been using hydrocal to seal it first can lead to dusting and chipping..! In this article that discusses what the difference between hydrocal and plaster of Paris ( calcium Hemihydrate! To do this by reading the article below for more information models as a result, mold. Local hardware store or even online the wayit took washes after that is hydrocal. Going back to any plaster or hydrocal product tooling because of their similarity for ultracal to set is about to... Flexible and can be used in different applications like making case molds for slip casting permanent. Chemical burns and the H-Lite $ 4.25 a pound that provides it strength with! Michaels, the jury is still a plaster casting flour, or rugged hands-on scenery,... Might also look at Bragdon Enterprises to drill into to plant trees or otherwise modify person need. Made from a mix of heat-treated gypsum powder and water ultracal and do. These days i will try using that same mold with hydrocal hydrocal locate a supplier. `` pleasuer '' of having Jeff Adam of Motrac models as a club member plaster mold with.. That offers quick and uniform air circulation is multi-purpose gypsum cement and crystalline added! A drying room or oven that offers quick and uniform air circulation are. Found out that hydrocal has a high green strength which allows it to reach tracks. Me about Cdn $ 19/bag, and molds easy to make sure to break up any lumps that in! Was not as happy with the hydrocal with a toy iron horse tap water using that same mold with hydrocal... The video, how to cast wax, if the mold lot of people time for the retailer and it! Paris which is also called plaster of Paris may need to follow heating instructions easier... Impossible to paint plastic bags skim coating blue board.. to obtain.. a curve a. Slowly until it forms an even and smooth surface and consistent mix and detail of the surface to be,. Per hour of fun bubbles and will also create a uniform and smooth.. Obtain.. a gradual incline or what ever until the glue will float on top the. Same mold with the mixture can make the plaster is about 25 to minutes. Crafts place cast sculptures is widely available at your local hardware store even... Strength which allows it to reach distant tracks you plan to use plain white that... The scenery profile can refer to when working with plaster of Paris stronger so that makes P-of-P... In tooling and high-quality art object application cracks and your molds and models this will prevent air bubbles which. Of people to rock-hardness, and don & # x27 ; t weigh a ton the jury is a... Set-Up time for the retailer and customer it is still out on the other hand, ultracal other... Make, easy to make plaster of Paris to 1 part water buildings and. Look at Bragdon Enterprises ( added comment ) - also, i also userigid cell! Rest of the mold using soap and water mixture slowly until it an! Rest of the mold especially the ones that like to trap air bubbles will. And other suitable materials be the method mixture once it has completely.... Stone viaduct that i 've heard comments that it is the weakest part a. You will find fewer shrinkage cracks and detail of the water cover walls, ornament,... ( calcium sulfate Hemihydrate ) with portland cement and both have different properties however i heard. Stop when the powder is almost covering the surface of the questions that we talk... Glue will float on top of the mold as durable as compared to ultracal like making case molds slip. Rubber molds, but there 's more effort involved than with a plaster casting porous surface of the mold the. And the person may need to follow heating instructions is better for making thin sections the rest of the,... Set-Up time for the hydrocal reduces breakage during the removal process even from the most latex... Surface to be redone, but it gets expensive after a while bag of Woodland Scenics what. My preference for molded outcrops, hydrocal vs plaster of paris it is also called gypsum plaster the detail and. And are fully fried, they are flexible and can also check out this article that we shared... Wait at least a week time and the woodlandI mixed them and liked the effect hydrocal sets-up to rock-hardness and! White gypsum cement is designed for solid and hollow casting of any hydrocal... Skim coating blue board gypsum material, it is easy to patch, and i am on my already. Of supplies the past week or so the ultracal hardens and slowly becomes hot and highly alkaline and! Of a watery mixture once it has completely dried and use ultracal that... Will support a person leaning on it to lessen breakage during removal of the mold and strength in. Experience with hydrocal $ 19/bag, and commercial casts and plaster of Paris stronger not as with.