There are various waterproofing agents that you can use which effectively seal the porous surface of the plaster. I tried use of colors mixed in the Hydrocal, and found that enough color to make any appreciable difference weakened the mixture after set-up, and any lesser amount resulted in pastel, not colored, rocks. Paste as plain text instead, You can heat ultracal, but you need to follow heating instructions. Shake the bubbles out and level of the castings. Because it is a multi-purpose material, it can be used in arts, crafts, and construction. Hydrostone and hydrocal are both gypsum products. 10 replies. 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. Real rock ballast is much better. So many choices but so little time. I will use that in the future. Hydrocal is waterproof. Use a mixing container that can fit the amount of mixture that you will make. What is the difference between Hydrocal and Ultracal? It provides a slightly better heat resistance as compared to pottery plaster with higher dry and wet strengths. Hydrocal doesn't take paint easily. Regardless you are making a cast or a mold for your art project, we will discuss two of the common materials that you can use which are hydrocal and plaster of Paris. All casts must be dried as quickly as possible so that they can develop maximum physical properties. The first thing that you need to do is to prepare the mix. Thank you for reading! The plaster of paris has a grittier finish to it, losing some of the detail of the mold. Pasted as rich text. Step 2: Weight the hydrocal and water at the required use consistency for each mix. Step 1: Use portable water between 70 to 100 degrees Fahrenheit. Of course, you want to immediately figure out what causes discoloration Building a house is rock solid. This website is strictly for entertainment purposes. As an Amazon Associate, we earn from qualifying purchases. Note: Your post will require moderator approval before it will be visible. I had to chisel some off the sides to remove the cast. Yes.. that is the weakest part of a mold.. a thin mold approach that I use. Many just use plaster of Paris and some even make polishing tools from a disk of plywood. I know this.. What is hydrocal? manage your account online and more! Others are a mix of production offerings and ones created by myself or club members. Most drywall muds are designed to shrink up more than platers or hydrocal type products. We hope to inspire you. Adding either Plaster of Paris or Hyrdocal to make a smooth surface should not be a problem, I have done it both ways lots of times. plaster should always be added to the water, not water to the plater. In this article, we will have an in-depth discussion about hydrocal. If this is the only foam you have at your disposal, you can line the form with packing tape. It is specially designed for close-tolerance tooling because of its accuracy, hardness, and flexibility. Like plaster, hydrocal is easy to use so it is a great option for making crafts and DIY projects. There are three types of plaster which are the plaster of Paris, lime plaster, and cement plaster. After thoroughly mixing the ingredients, you can proceed to the drying. I agree with A. Wallace on the superiority of hydrocal if you are looking for strength and clean castings Has anyone tried using drywall 'mud' in place of Hydrocal or plaster of paris? The pictures below are of a Hydrocal High Arched PRR prototype stone viaduct that I've been working on the past week or so. This will keep the product from absorbing moisture and affecting the overall mixing, and curing of the plaster over time. You can also check out this article that we have shared that discusses what hydrocal is made of. You might be washing the dishes when all of a sudden brown water comes out of the faucet and makes you wonder what causes it. The first step is measuring. Hydrocal molds can be heated at a maximum temperature of 120 F. link to Why is My Well Water Brown All of a Sudden? Avoid pouring all the powder into the water. A true friend will not bail you out of jailhe will be sitting next to you saying "that was friggin awesome dude!" To help you get started, we will discuss the differences between both materials below. So that makes the P-of-P 66 cents a pound and the H-Lite $4.25 a pound. Moreover, hydrocal is color white and has a setting expansion that is twice that of a molding plaster. While we strive to provide quality information, we cannot guarantee its accuracy. Thank you for reading! A higher drying temperature can be used without any difficulty using substantial free water in the mold. The castings can set in about 15 to 20 minutes. I tint mine with mortar dye, but if I decided to alter it in some way, would the shellac or varathane, whatever, not preclude painting over it..or will acrylics "take"? I picked it up off the floor.. looked for chips.. cracks.. nothing. There is a product called hydrocal light where the disparity may be truly noticeable. For life-casting, alginate (seaweed-based gelatin) is used for a (negative) mold, and plaster is used as the positive casting material. As said, try to locate bulk bagged Hydrocal locate a building supplier that specializes in drywall/ plaster products. We hope that the information that we have shared has helped you weigh out your options regarding the best material that you can use for your project. I watched him cut masters for many of his pieces and how he dammed and poured RTV for the molds. What is the difference between hydrocal and plaster of Paris? Always do your own research before making important decisions. What is plaster of Paris? I would be interested in others experience with hydrocal. I use 2 parts plaster of paris to 1 part water. Plaster statues are made from a mix of heat-treated gypsum powder and water that hardens when it dries. Product Details. I use "concrete patch" at the head of the stairs, where one tends to handle the ledge roughly. Hydrocal and ultracal sets quickly. TimModeling the NYCis there any other? But all three DEFINITELY have their uses. It's a slower method and takes longer to set up, but I like the results. Besides it has been used for years by model rail roaders, so my therey is if it aint broke dont fix it..Oh and plaster problems with bugs. Never had them in colorado. Login, or register today to interact in our online community, comment on articles, receive our newsletter, If you want the cast to be completely cured before you remove it from the mold, wait until it feels dry and warm. In the video, the process of casting in plaster from a waste mold is discussed. Let us learn more about this below. We have shared tips and ideas about the topic that you can refer to. We have shared information that can help you eliminate mold in your home. Like Jeff, I also userigid closed cell insulation for cast forms. They are flexible and can be used for various arts and craft projects. Decorating is poetry. On the other hand, the Bragdon castings can be heated with a hair dryer and they will become flexible again, which is nice for fitting around irregular contours. How Long Does it Take for Hydrocal to Cure? The difference between hydrocal and ultracal is that ultracal is harder and denser. This is another material that you can use as an alternative for plaster of Paris. has a longer working time so in my dry environment, it works better for covering plaster cloth. Both are plaster but have their differences. I usually 'paint' the basic Hydrocal 'hard shell' with Plaster of Paris, then use my rock stains. M. Many of the castings on our layout are his. You can also check out this article that we have shared that discusses if hydrocal is stronger than plaster of Paris. As compared to plastic, plaster can easily break especially if it is dropped. However, there are instances wherein you do not want the plaster to completely dry out before it is removed from the mold. Wearing gloves is also recommended. Generally, the maximum temperature at Ultracal molds can be heated safely is 120 Fahrenheit. My latex molds.. are very flexible.. and would suggest always to keep them out of the sun.. or light for that matter.. 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. The last step is drying. I truly believe that all you have to do is 'wet' your mold down. Always do your own research before making important decisions. I hadn't thought of the scouring of the surface to be redone, but I would expect that to be the method. If you find you like rock face and stone wall castings, you might also look at Bragdon Enterprises. This just take 10 seconds to clean. Is Hydrocal stronger than plaster of Paris? Hydrocal and ultracal are easy to use. so you must keep water and hydrocal at a stable temperature before using. You need to cover the work area using newspapers. For rocks and structures for a slot layout though regular plaster is probably OK. Save. 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 that we have shared that discusses the difference between hydrocal and ultracal. Step 5: Pour the slurry carefully into the deepest area so that it evenly flows across the surface of the mold. Hydrocal and plaster of Paris are two of the common materials used in casting, molding, and crafts, but is there a difference between the two? Dilute the detergent by spraying the mold with straight tap water. I am needing to do some landscaping. Grinding is a cave mans job, even the most simple tools will do. Make sure that the hydrocal is fully dispersed in the water before mixing. Let us learn more about this below. I cut my teeth using p.o.p. It might be Scenic Express. Moreover, you cannot use plaster of Paris to make miniature pieces. manage your account online and more. This is a basic mixing method that you can use regardless you are making plaster for mold or casting with plaster. Plaster of Paris is easier to work with in the mixing, carving, and the painting. I would still use real ballast. 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. The most commonly used plaster among the three is the Plaster of Paris which is also called gypsum plaster. Then really dry it. If you are wondering how hydrocal is used to create casts, you can check out the video below for the process. The reason for this is that the chemicals in the water can create unwanted reactions when it is mixed with the plaster. You see the way the spoon is? Get all the moisture you can see off the mold. This gave very nice results, too. Way stronger. You can do this by using a gauze bandage, glass fiber, and other suitable materials. When it comes to demolding the cast, you need to wait a couple of hours before you demold. It would do so after priming. I did try adding a little color to one batch and was not as happy with the wayit took washes after that. Tough geometry! Also called plaster of Paris, this medium has been used since ancient times to cover walls, ornament buildings, and cast sculptures. I'm also a hydrocal fan for plaster casting. Hydrocal White is versatile gypsum cement that is an excellent choice for making solid and hollow castings. Hydrocal has a very white color. Now, I use premixed drywall mud, over foam for the base, but still useplaster of paris for rock castings. So far, it is strong. Usually this is a lot cheaper than buying it in the Woodland Scenics format. There's also a Hydrocal rock face casting (WS mold) in there for good measure. When painting the plaster into the mold.. Then I apply small cloth strips over the 'high' area's of the mold. Moreover, the maximum temperature that hydrocal casts are safe from calcination is 120 Fahrenheit. I have used plaster of Paris for table and back castings for 25 years. Ballast - Most of the Woodland Scenics ballast appears to be crushed walnut shells(or something close). Moreover, dust particles from ultracal can cause skin, nose, eye, or throat irritation. It is made for thin sections and is also more durable so there is minimal breakage during mold removal. When coloring either Hydrocal or Plaster of Paris it's actually best NOT to paint it but rather stain it. To remedy this, you can seal the plaster of Paris. Hydrocal and plaster of Paris are both made for crafting and other applications, but they clearly have their differences. When hardened, it will permit removal of molds with "undercuts" whereas plaster of paris will break off detail. Check out the article below to find out what the difference is between the two materials. Your previous content has been restored. You can keep the surface of the casteasy to scrape by lining with cellophane and filling with sand while it cures over the course of several days. my photos. We use cookies to ensure that we give you the best experience on our website. Posted 11 May 2017 - 09:42 AM. I think Plaster is just fine I have used it before in high school for sculpture projects with no problems. I skim-coat my construction-foam base and hills with this, and it gets rid of the flats and gives me a nice rough earth-like finish. Avoid mixing vigorously because it can cause air bubbles to form. Description. What Can I Use Instead of Plaster of Paris? For a more in-depth discussion about this topic, you can check out this article that we have shared titled, what is hydrocal? Plaster of Paris is a gypsum plaster that quickly sets. We have also shared this article that discusses what hydrocal is made of. I wanted its superior strength. It is the perfect choice for making a solid and hollow casting of figurines, general sculptures, and commercial casts. Add cup of white glue into the water. Generally speaking though, I use Sculptamold 50/50 with water when I'm doing rock castings. As a result, the ultracal hardens and slowly becomes hot and highly alkaline. It is also an extremely wear-resistant material. "CLANK" was the sound, a high pitch clank. Back in my hardshell days, I used tri-fold paper towels (10 bucks for a case, and I still haven'temptied the case), and patching plaster ($7 for a 20 pound bag, enough for a 10 x 20 layout). The difference between hydrocal and ultracal is that ultracal is harder and denser. I use less plaster.. pour a thinner mold.. and is light.. but strong. We have also shared this article titled, what is the difference between hydrocal and plaster of Paris? It is true that Hydrocal requires priming before painting, but it is excellent for places that get a lot of hands-on use and for water proof base for rivers. bulk sand? Hydrocal vs Light weight Hydrocal vs Plaster of Paris and Ballast. You can also check out this article that we have shared titled, what is the difference between hydrocal and plaster of Paris? You might be washing the dishes when all of a sudden brown water comes out of the faucet and makes you wonder what causes it. The difference between hydrocal and plaster of Paris is that hydrocal is stronger. Continue adding the powder while frequently tapping the sides of the container. They Being old is when you didn't loose it, it's that you just can't remember where you put it. Should You Leave Your Shower Curtain Open or Closed? On the other hand, it is still a plaster that is heavy, dense, and can shatter when dropped. Mabye in more humid climates though. You can also check out this article that we have shared titled, how long does it take for hydrocal to cure? They soak up moisture, float, and even grow mold in some enviroments. Moreover, they are easy to prepare and can be set after just a few minutes. Sets fast in 20-30 minutes without shrinking. Left it sitting on the edge of my work table. Moreover, when making plaster casting, make sure that you use pure water. Hydrocal dries rock hard, so it is hard to modify or carve. Each step is important to make sure that the hydrocal will work properly. What has taken place.. you have removed the 'dryness' or 'surface tension' that is keeping the plaster from really getting in. Of course, you want to immediately figure out what causes discoloration Building a house is rock solid. When heated, the calcium sulfate loses some of its water content. Plaster molds can also be used to cast wax, if the mold is well-soaked beforehand. You can check out this article that we have written titled, how to make homemade plaster for more tips and information. We will discuss these differences below as well as which of the two is stronger. Trains. If you want the best product for pre coloring the plaster, use "Powered" Masonry Dyes. Well mix your plaster exactly like this. Plaster of Paris is an ideal material to use for craft and sculpture projects. Hydrocal is stronger than plaster of Paris. The ratio is vital because it will affect the physical properties of the final cast piece. If you are making mother and outer molds, it is best that you avoid using ultracal. After I was done.. Pour 1 cup of water into the mixing bowl. BUT. (there's that but again), make sure it's the slower setting type. Posted by willy6 on Tuesday, April 20, 2010 11:43 PM I have tried both. For more information about this topic, you can check out this article titled, what is hydrocal? While we strive to provide quality information, we cannot guarantee its accuracy. In this article, we will discuss the difference between hydrocal and plaster of Paris. Aside from that, it also takes a lot more detail. If you want to speed up the drying time, you can add a small amount of pure gypsum into the mix. Thicker batches will set faster and can be used for direct application to semi-hardened or bond hardened castings or for fill-in scenery. Ultracal is specially designed for strength and casting detail. But in short using the hyrdrocal/dental plaster. Strictly my O/P as some doe paint hydrocal to seal it first. It also has a darker color than the plaster I use, so I figured it could affect the final outcome of the colors of washes I planned on using on my rockwork. Plaster of Paris is not waterproof. In this article, we have discussed hydrocal, what it is, how to use it, and where to use it. how about ballast? After it becomes partially dehydrated, it turns into calcium sulfate hemihydrate. You have reached the end of this article that discusses if hydrocal is stronger than plaster of Paris. Well, the thing fell off the table and landed on the tile floor. For my club we could never afford using those WS packages. | Guide for Beginners. All these castings are pre colored. These are some of the questions that we will discuss in this article. 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. Hydrocal is a bit expensive, but worth the cost, for water-proof, or rugged hands-on scenery. I find I have no air bubbles.. and can apply a thicker coat afterwards. Aside from that, they are also durable and lightweight. you get far greater detail then you would by painting. I hadn't noticed the problem Don Z mentioned, but for certain types of rock it might be a problem. We have shared tips and ideas that you can refer to. I already had a two pound carton of Woodland Scenics Hydrocal Lite at $8.49. I believe these are offered commercialy now. Now for my last pic.. just a side note.. but someone out there might want to know. You need to achieve a nice thick soupy consistency. Hydrocal is mainly composed of plaster of Paris and a small amount of Portland cement. There are ways to overcome this most common is spraying the hydrocal with a mist of wet water before staining. You might be washing the dishes when all of a sudden brown water comes out of the faucet and makes you wonder what causes it. When working on anything of any size plaster of paris will flake and or brake off at the edges. You can use this product to cast rocks or make your castings. If you are thinking about using either two for your craft or building project, but do not know which one to choose, you can check out this article below for helpful tips and information. Hydrocal and ultracal have high performance. It took me less than 10 minutes to find one in my area and I bought a case for about $30.