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Helpful Information

Announcing! RTV Mold Making is growing up!

Happy New Year Everybody!

Great news! RTV Mold Making has evolved into Raw Material Suppliers

Raw Material Suppliers is an imaginative blend of manufacturers rep, stocking distributor, sourcing and consultant referrals.

We'll have access to more products from more sources than ever. Our Mission is to provide an uninterrupted flow of materials to our customers while delighting them with our service, quality, product selection and technical knowhow.

Raw Material Suppliers will feature RTV Mold Making silicone and add silicone ink, epoxy, mold release, urethane casting resin, adhesives, mold maintenance products, and plastic purging compounds. We want to be more valuable to you than ever before so we are now "sourcing". To source products means we scour the earth with your requests for associated products. We are quite resourceful and will add common products resulting in an ever expanding product line.

RTV Mold Making will be open during the transition then will point to Products are being ported over every day so please check out the new site!

Visit us at and please pardon our dust while we get ready for your formal arrival. Help me shape the company ~ send in your ideas ~ comments ~ wants ~ needs ~ you get it!

Thank you for your continued support!

RTV Steve

RTV Mold Making website and product revamp

RTV Mold Making is doing a complete revamp of its product line and website. We are partially running until about the 1st of the year. Happy Holidays - Merry Christmas - Happy Hanukah - Good Ramadhan and thank you for a fantastic 2010!

RTV Mold Making closed for two weeks

RTV Mold Making will go offline today for a complete revamp. We plan on reopening before 1-1-2011

Thank you

RTV Steve

Sale on 4 pound kits of Magikast Off White

We have another batch of the Off White Magikast OW. We are discounting the kits to $35.00 delivered to your door!

New version of Magikast

The Economy version of Magikast is starting to trickle in! We have 16 small kits of the off white Magikast 180 now available for testing and usage. The new version, when finally available in all packaging, will be at a lower cost that the existing product. Right now it's off white but we may change that after hearing from you. We can make it white like the other if that's what everybody wants. I like to know the difference once the part is made, some don't want to know. The existing product will still be available and we have no intention of discontinuing it - it's a very high quality resin. In today's market we wanted to offer an economy model also! Regular inventory is two weeks away and web pages will be posted soon.

Thank you,

RTV Steve

Magikast Series New Products - OLD PRICE

In about a week we will post new Magikast Series products at our previous prices. We will offer two versions the existing version and a new one we've been working on. If you have an immediate interest or just can't wait contact me and I'll speed it up! More information to follow...

Thank you all for your continued support!

RTV Steve

Magikast Series Price Increase


Due to raw materials cost, plastic container costs and now transpostation costs the Magikast line of products will have a price increase to be effective on 7-5-2010. We are working to keep the cost as low as possible. Thank you for your continued support!

Casting Resin and Moisture Contamination

Hello Everyone,

We have had several instances of moisture contamination in the field recently. Some were caused by just not knowing water will contaminate urethane casting resin. Polyurethanes are moisture sensitive materials. Polymers that are exposed to moisture may form an in-dissolvable skin on the resin surface. The skin can be removed and, if no additional particles are noted in the material, a small amount of resin and hardener can be mixed and cast to ensure that the remaining resin system is usable. However, if the moisture contamination is severe, the polyurethane may become foamy in appearance, indicating that the product can no longer be used to prevent moisture contamination, opened containers of resin and hardener must be resealed carefully. To begin, clean the lip of the container with a rag or paper towel to remove any material residue. Next, spray dry nitrogen into the open container. Finally, replace the lid ensuring a tight seal.

Moisture containing materials, like plaster and wood, should be properly sealed and released before castings are made against them. Otherwise, when the casting resin exotherms (heats up) during the curing process, the heat will draw out the moisture and create surface porosity or bubbles or foaming in the casting. Using sanding sealer, wax and PVC or PVA film barriers is the best way to protect the casting.

Magikast series casting resin are robust against moisture contamination yet still can have the issue from time to time. Moisture, humidity and water are contaminants for urethane casting resin.

For more information go to

February Specials

Hello Everyone!

Check out this months specials:

Magikast 90 10 gallon kit - Normally $357.00 February Special $340.00

Magikast 90 2 gallon kit Normally $95.70 February Special $89.00

Magikast 300 10 gallon kit - Normally $357.00 February Special $340.00

Magikast 300 2 gallon kit Normally $95.70 February Special $89.00

Magikmold 28 Silicone Mold Rubber - Normally $95.00 February Special $89.00

Magikputty PF40 Food Grade Silicone Putty 2 pound kit Normally $77.00 February Special $39.00 (Only 5 available)

Food - Soap - Candle Silicone Mold Making Rubber - 8A Durometer - 4lb kit Normally $75.00 February Special $55.00

See our Hot Useful Links page where you'll see which is a great training site for marketing on the internet and don't forget Free Download How To's for Mold Making at

Until next time...

RTV Steve

Sale of Magikast 90 Original Version

We've been stocking the original version of Magikast 90 for one customer and they over ordered. I have 6 kits for sale that weigh 80 lb each and will go for $327.00 delivered. Only 6 kits so please take advantage right away. It's the original 1:1 fast cast white resin.

Here is one company using the resin to make windmill blades. These are small wind turbines that are only 72" in diameter and install 10 - 30 feet high, pretty low eh? One windmill can power 1/2 to 75% or more of all your power needs. I hear people are getting $5.00 electric bills.

I also discovered this link for anyone who would like to pursue making money on the internet. I really like this company and training.

Until next time...

RTV Steve

Soft Silicone A Winning Combination Of Delicacy, Detail And Durability

The Italian Manufacturer Says That P008 Platinum Cure Silicone Is Just Right For Mold Making Due To It's Considerable Precision And High Dimensional Stability. I say If You're Seriously Interested In Soft Silicone To Make Delicate Parts Then Magikmold P008 Should Be Perfect For You.

A Handy One To One Mix Ratio And Thin In ViscosityThis Silicone Is Splendid To Use. Proven For Food Molds, Soap Molds, Candle And Resin Molds – It's The "Holy Grail" Of Silicone Mold Making. Magikmold P008 Is Almost As Thin As Water Or SAE 60 Anyway... Mix Equal Amounts Of A & B For A Rubber Mold That Is Perfect For Your Most Delicate Pieces. Make Your Fanciest, Finest Detail, Hardest To Mold Parts With Magikmold P008.

Translucent In Color - Cure Zips Along In Two Hours At Room Temperature. Faster With Heat.

Right Now, I'm Inviting You To Try Magikmold P008 While Introductory Pricing Is In Place

Let Me Emphasize That This Is Your Silicone If You Make Food, Soap Or Candle Molds! Soft Enough For Those Delicate Pieces And Will Take A Fingerprint Off Of Glass... Reproduce Fine Detail With Magikmold P008 Package Includes 4 Pounds Total; 2# Of "A" And 2# Of "B".

Free Freight

Magikast Series featuring Micro Sieves


Everybody want's to know how the Magikast Series produces bubble free parts even when using Magikast 90; the fastest of them all. The secrete is Micro Sieves - the cloudy stuff you see on the B side of the material. You see these Micro Sieves scavenge moisture and prevent it from causing bubbles in your part! This makes for a longer lasting material on the shelf too! Shake it up and it stays in suspension all day.

Micro Sieves are just one of the reasons Magikast Series Casting Resin is the best on Earth!

Magikast True 1:1 by volume mix means you never have to weight it. It's easier to use and really tough!

Magikast Series comes in 2 gallon kits, 10 gallon kits and 55 gallon kits

Now available with FREE FREIGHT

How to stain Magikast Resin

A lot of people want to stain Magikast so I went to the experts - those that do it every day - for instructions. The photos shown are Magikast stained by taxidermists and following are the instructions as given to me by the artist. This is the first method being presented as I believe there are more. I'm told acrylic stains will also work... more to follow.

Oil based paint in paste form is recommended. It comes in a tube and one recommended brand is Gamblin Oil Colors

A dab of this paste is added to a bowl and diluted with lacquer thinner. This helps give a bite into the urethane so it sticks better and will not leach off. A nice paint brush was dipped into the mixed slurry and then coated at the base. The artist coated this very heavy, filling all the voids. He then slowly pulled this base towards the antler tines.

He then mixed a second slurry using less oil. (You'll notice that the oil based paint that I attached is expensive. But, you don't use much of it.) This second slurry was lighter in color and was painted over the rest of the cast. It took Terry some time, but eventually the entire rack was coated.

After it dried for an hour or so, he sprayed the entire piece with a clear-laquer based spray, not Krylon. Apparently he had problems with the Krylon hazing over the cast.

I've looked around and there are many oil based paint sources all over the internet. Here are a couple of links Windsor & Newton on eBay and UTRECHT seems like they have great prices

Magikast 300 for Rotational Casting Now Available -True 1:1 by Volume Featuring extremely Low Shrink, Whiter White and Stronger Properties. Magikast 300 Roto Cast Resin

PRODUCT ANNOUNCEMENT!! Magikast 300 for Rotational Casting now available True 1:1 by volume mix means you never have to weight it. It's easier to use and really tough!

The linear shrink rate is an amazingly low .001 - .005 (in./in.)

Magikast 300 is a 1:1 mix white plastic resin that sets in about 5 minutes. Make Hollow Parts that are amazingly strong Magikast 300 produces fine detail and has almost no odor. It is paintable and stainable - it's a very tough resin.

The resin is ideal for Rotational Casting, very strong hollow parts, and parts where a longer pot life is desired. Still great for making architectural parts, figurines, model railroad parts, toys and toy soldiers, fixtures, etc... Magikast 300 is commonly used in the production of small parts for Slot Machine Toppers, any sculpture reproduction, cold cast bronze, furniture hardware, replicas and more.

Magikast 300 comes in 2 gallon kits, 10 gallon kits and 55 gallon kits

Now available with FREE FREIGHT

Improved Magikast 90 Fast Cast Urethane Polymer Liquid Plastic Now Available -True 1:1 by Volume Featuring extremely Low Shrink, Whiter White and Stronger Properties. Magikast 90 Fast Cast Resin

PRODUCT ANNOUNCEMENT!! Magikast 90 one of our finest products is now better. True 1:1 by volume mix means you never have to weight it. It's easier to use and molds will last longer.

The linear shrink rate is an amazingly low .001 - .005 (in./in.)

Magikast 90 is a 1:1 mix white plastic resin that sets in about 90-120 seconds. You can demold most parts in 10-12 minutes. Magikast 90 produces fine detail and has almost no odor. It is paintable and stainable - it stains like wood.

The resin is ideal for making architectural parts, figurines, model railroad parts, toys and toy soldiers, fixtures, etc... Much of industry uses this resin for everything from industrial prototypes to collectibles. Magikast 90 is commonly used in the production of small parts for Slot Machine Toppers, any sculpture reproduction, cold cast bronze, furniture hardware, replicas and more.

Magikast 90 comes in 2 gallon kits, 10 gallon kits and 55 gallon kits

The new version is available now!

Tin? Platinum? I wanted Silicone not Metal

What's all the fuss about Tin Cure vs. Platinum Cure? Does it make a difference to me? It's smart to know the differences because there are reasons to use both. First the similarities are; both are two part rubbers where "A" is mixed with "B" then the end result is a flexible rubber. Both pick up the finest of detail and both cure at room temperature and offer excellent release properties.
The differences begin where Tin aka Condensation Catalyzed Silicone Rubber is easier to use. It will cure over most everything (it's not sensitive to inhibition)! It is safe near sulfur clay (although in very fine area's a sealer is recommended) and safe in most any shop environment indoor or out. Tin Cure silicone is Easy to mix and degas and has very low shrinkage. Many Tin Cure Silicone users do not degass at all and make very fine long lasting molds. Some pour from high up; even standing on a ladder in order to break bubbles while pouring. Typical in use temperature can be as high as 325F. Curing temperature is important but humidity is most important in curing this rubber. If it's 25% or 30% humidity outside and you haven't added moisture to the air a mold could take days to dry. Most cure times stated on data sheets are based on 70% relative humidity.
Platinum aka Addition Catalyzed Silicone Rubber is more precise with virtually no shrink and cure can be accelerated with heat. This silicone can be warmed with heat lamps or put in an oven - it loves the heat. Cure extremely fast with heat. Platinum cure rubber is sensitive to cure inhibition. Surface inhibition means wherever it has touched a contaminated area the silicone will remain tacky. Gross inhibition means the stuff doesn't harden at all - a gooey mess. See your data sheet for a specific list of contamination causes. COLD will cause slow cure... for every 10 degrees below 70F DOUBLE the cure time... really for every 10 degrees below 70F DOUBLE the cure time Platinum Cure silicone should be used when casting low temperature melting alloys like lead and pewter. It will take temperatures of 500F constant and up to 700F or even greater for short times. Platinum used to be considered harder silicone and they do come in harder versions than Tin Cure however technology has advanced and many excellent low durometer Platinum Cure Silicones are available. Magikmold 20 1:1 mix is a great example as is Shin-Etsu KE-1300T with Cat L-3 30 durometer or Cat L-4 40 durometer catalyst. Platinum cure rubbers make the very best molds for CONCRETE Casting. Platinum cure silicone will not shrink in service.

Aqua-Resin® | Non-Toxic Casting, Laminating, and Sculpting Resin now available at


Aqua-Resin® now available at RTV Mold Making

Water based, water cleanup, fire rated, AQUA-RESIN® is an easy to use, opaque, non-toxic composite fabricating resin. Used in casting and molding and is primarily used with fiberglass reinforcement for Indoor and Outdoor Architectural Facades, Themed Environments, Mannequins, Figures, Repair and Restoration, Flame Rated Foam Coating, Tooling, Backup Tooling, Sculpture, Prototype and Product Development.

SAFETY Non-Toxic*
Water-based, water-borne
No irritating fumes
Class "A" fire rating - Laminating resin

Permanent in all interior as well as most exterior applications, it has numerous uses in such diverse fields as scenic design, architecture, sculpture, and prototype and product development.

AQUA-RESIN®'s unique system offers easy to use, water based - water borne, non-toxic, opaque, molding, laminating, and casting materials without the usual health risks or fumes generally associated with conventional or formaldehyde based resin systems.

All Aqua-Resin® coating and laminating products were developed to fill a need, not only for safer materials, but also to provide working properties and versatility not found in other materials.

See the Aqua-Resin® link at