How do I use Clear Casting Resin?


Developed for the purpose of encapsulation or suspension of an object or objects in a desired thickness of transparent, glass like resin, this is generally applied in stages of no more than 15mm-20mm thick segments. Clear casting resin has been engineered so that each time the resin cures it leaves a tacky surface for the next layer to be applied. This tacky surface is only present on the surface exposed to the air; it remains sticky for around 5 - 7 days post cure.


When the encapsulation is complete a sheet of acrylic or ‘plexi-glass’, from 2mm in thickness can be laid on top of the final cast, this use of acrylic sheet has a dual purpose. It flattens the inherent ocean-like rippling surface of the cured resin, giving a flat and more professional finish, it also creates a barrier between the resins inherently tacky surface and its user with a more durable, tack-free surface.

Remember clear casting resin is polyester and all polyester resins need a MEKP catalyst, or equivalent, at a ratio of 0.75g to 4 grams for every 100 grams of resin, depending on the size and volume of the casting. Always check with your technician which percentage is best for you.


For example, when casting a large object enclosed in a split mould we will only use the minimum amount of catalyst required for curing (0.5 - 0.75 %) this way, as the resin shrinks, as all polyesters do at a rate of around 2%, it will minimise distortion and the usual rivulets of resin which may form on the surface of a casting. These rivulets form as a direct result of the resin shrinking too early or too quickly in mid-cure and it pulls away from the sides of the mould, much like the effect you see if you touch wet paint and it leaves behind a rippled surface as you pull your finger away.


Similar products such as clear polyurethane resins and crystal clear wax are also     

available on request.




 

Clear Casting Resin

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Health and Safety


When working with these resin’s we must always wear protective gloves and goggles, long  but not baggy, sleeves are advisable especially if you have sensitive skin.

The use of an adequately ventilated working area (like our workshop) is essential. If you are using any polyester for a prolonged period or using a particularly large amount, then the additional protection of a respirator, to protect yourself from the fumes is advised. The fumes can make you feel light headed and a little nauseous if you are over exposed to them.

   

   

Clear resin casting + with white pigment

   

Painting/layering with clear resin pigments

Clear resin, wicker and wood shavings

   

Gold/silver leaf and resin lighting

Encapsulation Tips


Best results are achieved by using a clear acrylic tray with a separate piece that fits inside the tray with room to spare, this will act as the top cover. Once you have finished your  resin encapsulation in the tray, mix enough resin to cover the surface in a thin 1mm layer. Using the top cover that fits inside the tray, lay one end onto the wet resin surface and slowly lower the other end. This will chase all the bubbles from under the top cover.


Once fully cured, after a day or so the sides of the tray may be cut off using a band-saw, and sanded flat using a disc sander. Encapsulations can also be cut into any shape or sliced up like a loaf of bread! All sanded surfaces can be finished and polished following the instructions below.


Remember: any material can be encapsulated (sealed in a resin block) so long as it is dry! So any food that is freeze dried or naturally dried, dried flowers, rice, pasta, even dried mud, gravel, sand, fabrics, silk screen prints, even layers of acrylic paint and marker pens will work. Organic materials that will rot (including animal produce) are not suitable for encapsulations.


The key point to remember here is that polyester resin hates water and anything that contains moisture.



Price is around £8.00 per kilo




Finishing / Polishing


To flatten off and polish the surface of cured resin to a glass like shine is a relatively simple process. Begin by rubbing your object down first with at least three grades of wet and dry sandpaper, starting with a 180 or 240 grit depending on your initial surface quality. Continue working through the grades in ascending order, such as 320, 400, 600, 800, etc. Deep scratch marks show up white and will not polish out, they must be sanded out by progressing through your grades of wet & dry paper. When the surface of your object looks like frosted glass with a satin texture it is ready for buffing!


You will need to ask me to demonstrate how to achieve the best finish for your product if you choose to use it.

 Shredded paper soaked in clear casting resin
         ‘Bubble wrap’ clear resin castings
    Encapsulated silk print
   Encapsulating metal wire
 Tinted lens-like lighting