Congratulations on your purchase of our soft Flex&Bake™

Flex & Bake ™ Platinum is a flexible yet strong, high quality food contact safe silicone that is ideal for chocolate casting, working with sugar and baking.

We want your mold making experience to be trouble free and have included this document to help you get a good start. To see mixing/pouring photos please visit our:

Flex & Bake ™ Fast Facts

Mixing Ratio

10 parts Base to 1 part Catalyst by weight. (100 gm base/ 10 gm catalyst)

Mixing

Stir catalyst before mixing. Mix base and catalyst together until the color becomes uniform violet and then mix for two more minutes. Be sure to scrape sides and bottom of mixing bucket to ensure catalyst activates all material.

Pouring

Flex & Bake™ will not cure against all surfaces. Use only Klean Klay if sculpting a clay model. If you are not sure if it will cure against your model, make a test cure or call us.

Curing

Flex & Bake™ will take 24-36 hours to cure. Cold working areas will slow down the cure; hot working areas will accelerate the cure. After silicone has cured and is removed from the model, bake in an oven at 400°F for 6 hours and then wash with soap and water before use. Or, you can run the new molds through two consecutive cycles in your dishwasher (industrial style is ok).

Cleaning

Use warm soapy water and a soft sponge to clean your finished molds. Do not store molds wet (dry in oven) and do not store your molds wrapped in plastic wrap.

Storage

Store all of your molds flat. Molds might become lighter in color after time. This does not affect the integrity of the mold. Place parchment paper between molds when storing in contact with other silicone molds. Flex & Bake™ silicone may bond with other types of silicone if left in contact for a long time.

General Safety and Handling information

Safety

1. Always wear gloves, goggles, and an apron when working with mold making materials.
2. Do not use or store mold making materials in areas where food is stored or prepared. (Using a mold in the kitchen is not the same as making a mold in the kitchen).
3. Keep all mold making materials away from and out of the reach of children.
4. Need more information? Please contact us at Joy@ChicagoMoldSchool.com or call 708-660-9707.

Clean up

If the silicone is spilled, wipe it up with a paper towel then use Goop to clean the surface area. Goop Hand Cleaner is a safe (citrus based) and inexpensive solvent for removing silicone and is available at most hardware stores.

Preparing a work surface

Keep your tables clean by putting a layer of plastic wrap on the table top followed by a layer of butcher’s paper. Work clean, work smart.

Mixing containers

Use only dedicated mixing containers when working with mold making materials. Do not use spatulas or mixing buckets that will be returned to the kitchen. To clean out a mixing bucket, simply let the residual mold making material cure overnight (drips and all). The silicone will not stick to the bucket and will peel easily off the bucket the next day. Helpful Hint: Remember not to let silicone cure on the spatula tip. Wipe off spatulas after use. Most spatulas are silicone and the mold making material will bond to it.

Storage

Store all mold making materials out of reach of children and away from food sources. Keep the containers clean and do not allow them to freeze. Flex & Bake™ has a shelf life of 12 months. Material used after this time is likely to still work; however it should not be used for food contact applications.

Food Grade Status

Flex & Bake™ is a food contact safe silicone when it has been properly mixed, post cured and washed before use. You are responsible for these activities and are also responsible for the food ingredients that are put into the molds. Return to Top

How to use the Safety ID tag

A Safety ID tag (included with Starter Kits only) is used to emboss important user information into the outer edge of your silicone mold. The tag can only be used when .5 inch or of more silicone will be poured into the mold box.

1. Clip the tag onto the interior of your mold box. The embossed words should face towards your model.
2. Do not let the tag touch the model.
3. Make sure the tag rests 1/8 inch above the surface of the work board. It should not touch the work board.
4. Pour the silicone into the mold box and allow it to cure. Remove the tag when de-molding.

How to Mix your Flex & Bake™ Silicone

1. To mix silicone, weigh out the estimated amount of Base you will need into a clean plastic container.
2. Add 10% Catalyst (by weight) to the Base and mix it together.Sample formula: 100 grams Base + 10 grams Catalyst YOU MUST STIR THE CATALYST BEFORE USE.
3. Continue mixing slowly (do not whip) until the silicone takes on a uniform color and there are no visible streaks of unmixed Base. Be sure to scrape down the sides and bottom of the mixing bucket with your spatula. If mixing a large amount of silicone, empty the first mixed amount of silicone into a second clean bucket. (This is called turning the mix). Use a spatula and scrape empty the first bucket into the second and continue to mix the silicone thoroughly for another two minutes. Turning the mix helps eliminate unmixed material trapped along the sidewalls or bottom of the bucket.

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How to Pour your Flex & Bake™ Silicone

1. Hold the bucket of silicone about 18-24 inches above the mold box. Pour the silicone into the mold box in a slow and steady stream. (Pour directly on the model). Pouring in a thin stream (1/8 inch thick or less) is called ‘needling’ and it helps prevent air bubbles from getting into the mold.It works like this: After mixing the silicone, you will notice a lot of air bubbles in the mix. However, if you pour slowly and from high above the model, the silicone stretches into a thin stream. As the silicone stretches, the air bubbles are also stretched causing them to burst before they reach the mold box. Using this simple pouring technique reduces the air bubbles by at least 80%.
2. Pouring directly on the model is preferable because the downward pressure of the liquid silicone helps keep the model stationary. If you were to pour all the silicone into a corner of the mold box and let it flow across the mold box, the weight and pressure of the silicone might push the model loose from the work board. (Think of the silicone as a thick wall of lava pushing its way across a street. Anything in its way will be pushed along with it).
3. Pour only enough silicone to cover 1/8 inch above the highest point of your model. Pouring more than this is a waste of material and will make your mold too thick. If your mold is too thick, it will be less flexible. If your mold is less flexible, it is likely to break a chocolate casting when you try to flex it out of the mold.
4. Helpful Hint: Always have a second mold box ready to receive extra silicone. If you do not have a box ready, put the liquid silicone in the freezer to delay curing while you prepare a second mold box. Putting the liquid silicone in the freezer will buy you about 15-20 minutes.
5. Allow the mold to cure undisturbed (on a level surface) for 24 hours.

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Making your Flex & Bake™ mold Food-Contact Safe

In order for Flex & Bake™ to achieve its food contact safe status, it must be properly cured. There are two good ways to do this. The easiest method is to put your molds in a dishwasher and run it through two consecutive cycles. The second is to heat your mold in a 400° F oven (without food) for 6 hours. (Make sure to take your mold off the work board and remove the model before putting it in the oven). After the mold has post (heat) cured, wash it thoroughly with soap and water. Dish soap and a soft sponge will work nicely.

How to store your mold

Do not store Flex & Bake™ molds in contact with other types of silicone molds as they may bond to them over time. Store all of your molds flat with the detail facing up (covered with parchment paper). Molds stored in an irregular pile will warp and can retain a bent shape. Keeping the detail surface covered with parchment paper helps prevent dust or other debris from settling inside of the surface of the mold. Remember; always wash your molds before use, especially after they have been in storage for a long period of time.

Flex & Bake™ FAQ’s

Can I bake with my Flex & Bake™ mold?

Yes. Flex & Bake™ silicone is rated for continuous use in high temperature environments. The safe temperature range for continuous use is 400° F/232&deg C. Flex & Bake™ can handle temperatures up to 450° F as long as the exposure to heat is not longer than 30 minutes. Do not use Flex & Bake™ in a hybrid microwave/convection oven as the temperatures exceed safe use levels. Over time, Flex & Bake™ may lighten in color. This has no effect on the integrity of the material. Return to Top

Will Flex & Bake™ bond to my model?

The following reference lists are intended to offer a quick glance at what will and won’t work with Flex & Bake™. If you have any doubts, do a test cure on your models surface before mixing up a large batch. (It is better to take the time to do a test than to waste silicone and loose a model). Flex & Bake™ WILL BOND to these surfaces.

1. Itself (cured or uncured).
2. Other silicone surfaces (like mixing spatulas, Silpats, Flexipan molds etc.)
3. Fibrous material, such as cloth, carpet, hair or fur.
4. Hand made/pressed papers and textured wallpapers.
5. Freshly spray-painted surfaces.
6. Porous surfaces like tree bark.
7. Most types of foam.
8. Your valuable antique frame or artifact. (Don’t mold valuable things. It is too risky).
9. Delicate piece of jewelry. (Don’t pour liquid silicone on real jewelry. It will seep beneath the mountings).
10. Loose weave materials like baskets and wicker.
11. Do not use Flex & Bake™ for body casting!

Flex & Bake™ WILL NOT BOND to these surfaces. It is not necessary to use release agent when molding them.

1. Klean Klay
2. Clean metal objects
3. Stone
4. Wood (like Pine and Poplar and other smooth surfaced, non-glue filled)
5. Hydrocal
6. Most types of wax
7. Plastic and resin objects.
8. Glass and crystal
9. Plexi-glass
10. Glazed ceramic objects (dishes, tiles etc.)
11. Unglazed ceramic objects (bisque ware)
12. Cement (smooth)
13. Leather (not waxed)
14. PVC pipe
15. Vinyl backed textured wallpaper

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How do I seal the surface of a model so Flex & Bake™ will not stick to it?

A light coating of Vaseline will usually do the trick. Use a heat gun to help liquefy the Vaseline onto the model. Liquefying Vaseline helps it to soak into a porous surface. Always wipe off excess Vaseline; too much Vaseline will inhibit the cure. If you can see the Vaseline, there is too much on the surface. Remember, porous objects like paper can soak up a lot of Vaseline and inhibit the cure; be careful not to use too much. Helpful Hint: Many companies will encourage you to buy aerosol based spray releases. I do not recommend using them unless you have a spray booth. Atomizing the release agents only mean they are easier to get into your lungs and eyes. Spray releases can be nasty.

Will I have difficulties with Flex & Bake™ curing against certain materials?

Platinum cured silicones can fail to cure against some surfaces. Some people do not like to work with Platinum’s because of this problem. However, if you know the material’s properties, you can successfully pull a mold from it provided it has been properly cleaned and sealed. (The following list outlines the most common materials people have trouble with when working with Platinum cured silicones. This list assumes a sealer has not been applied to the surface).

1. Flex & Bake™ WILL NOT CURE against a surface which has had liquid tin cured silicone poured onto it.Example: You have a small picture frame that you poured non-food safe tin-cured silicone onto to make a mold. Later, if you want to make a food safe mold of the frame and pour Flex & Bake™ on top of the same model, the Tin residue (which you cannot see) will inhibit the cure of Flex & Bake™. Your mold will be a useless gummy mess. Do not mix Tins with Platinum./
2. Flex & Bake™ WILL NOT CURE against vinyl strips or vinyl sheets.The chemicals in most vinyl materials will inhibit the cure of Flex & Bake™. (This does not include vinyl-backed wallpaper, which molds very nicely)
3. Flex & Bake™ WILL NOT CURE against sulfur based modeling clay.Oil based clays like Roma Plastilina have sulfur in it. Sulfur inhibits the cure of silicone (both Tin and Platinum). If the clay has a strong, stinky odor, do not use it.
4. Flex & Bake™ WILL NOT CURE against some waxes on fruits and vegetables.This is usually not a problem, but we have seen the material inhibit against the surface of waxed pears.
5. Flex & Bake™ WILL NOT CURE against Super Glue.If you use super glue to attach your model to a work board, make sure none has squished out the sides. If super glue is left exposed to Flex & Bake™, it will inhibit the cure in those areas.
6. Flex & Bake™ WILL NOT CURE against certain types of leaves and wood.Leaves and wood are organic materials. Trees produce a wide range of chemicals (saps and oils), some of which will inhibit the cure. It is best to make a small test cure before molding leaves and wood.
7. Flex & Bake™ WILL NOT CURE against engineered wood with melamine (dark brown stuff).Many types of wood from the hardware store have different types of glue in them. (Particle board and press board are half glue and half wood chip). The smooth dark sheets of melamine are tempting to use as work boards or for model making, but the glue in the wood can inhibit the cure. Pine, poplar and plywood will mold well.

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Helpful Hints for molding a variety of materials

If you are about to make a mold from a material you have not worked with before, take a few minutes of your time to peruse these molding tips:

Paper

Almost any type of textured paper can be molded with Flex & Bake™. However, the paper will stick to the silicone and can only be removed by casting liquid resin into the mold repeatedly. This in turn makes the mold non-food contact safe and you must then make a master mold and pour a new food safe production mold. (Time consuming work indeed…) It is much easier to mold vinyl based textured wallpapers, which does not stick to Flex & Bake™.

Wood

Some types of wood contain glue or sap that can inhibit the cure of Flex & Bake™. Make sure to do a test cure first. When molding heavily textured surfaces like bark, expect the silicone to bond to the wood. (Think of tree bark like Velcro, lots of hooks and texture for liquid silicone to flow into). Remember, wood floats. Make sure your model is securely attached to your work board.

Glass

Molding on glass will duplicate the material’s smooth surface and make a wonderfully shiny mold. A shiny model = a shiny mold = a shiny casting. BE CAREFUL, because glass can fracture unexpectedly during unmolding or when you are pressing it onto your work board. This would be a serious hand injury which would send you to the hospital.

Plastic Toys and similar objects

Flex & Bake™ will cure against most machine made toys. The trick is to realize that toys are assembled from many individual components. Trying to mold an entire doll might not be the best idea. Consider molding the arms, legs and head separately as the original manufacturer did. They did it for a reason. They also copyrighted their doll for a reason. Make sure your use of the toy falls under ‘fair use’ such as educational purposes. Remember, plastic floats. Fill it with clay or hydrocal and make sure it is securely attached to your work board. Warning: Some plastic dolls from ‘dollar stores’ are made of cheap plastic containing chemicals that will inhibit your silicone. Sounds funny, but brand name dolls seldom have this problem.

Antiques

Antiques are tricky. Your beautiful gold frame might make a great mold, but it would be a shame to see all the gold leaf peel off in the mold. Or, perhaps worse, to see the silicone seep into every crack and crevice in the frame, never to be removed again. Been there, done that. Antiques are delicate. If you value it and would miss it, don’t mold it.

Body Casting

Flex & Bake™ is not for skin contact. If you want to cast from the body, use Alginate, especially for making molds of hands and faces.

Things That Float

Having a model bob up through liquid silicone is a real drag. Make sure your model is securely attached to the work board. If you cannot get it to stick to the work board, pour a small amount (thin skin) of Flex & Bake™ over your model and let it cure overnight. The next day, the cured material will look like it has shrink-wrapped your model onto the work board. Now you are ready to pour more silicone over your model. Helpful Hint: If you are molding a large ball-like object, pour the mold in several stages, otherwise it will float up even if you ‘glazed’ it to the work board with a thin layer of silicone. It takes more than a thin layer to hold down a highly buoyant model. Be patient with the process. Do not rush it. It will be an expensive lesson.

Clay

Flex & Bake™ does not adhere to most oil based clays, but it can stick temporarily. Save yourself the time and frustration of scrubbing oil clay out of a mold by putting some release on the clay before molding it. A light coating of Vaseline on the clay will do the trick. Which do you prefer, an hour of scrapping out your mold or an extra 5 minutes of putting Vaseline on the clay before molding? FYI, Flex & Bake™ will not stick to water based clay.

I want to make a clay sculpture. What type of clay should I use?

We have found Klean Klay to be the best. It is sold in some hobby stores or can be purchased in our store. Return to Top

What is the difference between Platinum-Cured silicone and Tin-Cured silicone?

Chemical differences aside, Platinum cured silicone is a more durable material. Platinum molds should last 3-5 years or longer, whereas tin-cured molds last about a year. The general rule of thumb is: the softer the mold, the shorter the life. As tin-cured molds cure, they give off alcohol and water. This causes the mold to shrink over time. We use a lot of tin-cured silicone in our shop, but we do not expect it to last a long time. Old tin molds lose their elasticity and become fragile and tear like firm tofu. Helpful Hint: Save your old molds for recycling. Ground up silicone, or ‘regrind’, can be mixed into a new batch of silicone. (Use only platinum regrind with platinum silicone). For regulatory reasons, we do not use regrind in molds that are for food use.

How long will my silicone mold last?

Silicone molds are not indestructible. In fact, they are delicate tools that need to be properly cared for. The longevity of a silicone mold varies. For example, a soft silicone mold used for casting chocolate will last longer than the same mold used for casting Isomalt. Why? When pouring Isomalt into a finely detailed silicone mold, the Isomalt will flow into every detail and when the Isomalt cools, it shrinks slightly. This means that the Isomalt shrinks into the small details of the mold. When removing hard Isomalt from the mold, the rigid Isomalt acts like Velcro onto the detail of the mold. It can ‘grab’ onto the delicate silicone and can stretch and tear it upon removal. Over time, detailed molds loose their detail because of this type of tearing. Always de-mold your castings carefully to avoid stressing or tearing the mold. It is the nature of the beast. To avoid this, many commercially available molds are smooth and rounded. Remember, silicone molds can help you make amazing things, but they are delicate. Take care of them. Good luck with your project and please keep in touch with us. If you would like more mold making instruction, please visit our website for information about our 3 day, hands on workshops. We hope to hear from you! -Mold Making Team Return to Top