BK-A SERIES · PLATINUM-CURE SILICONE

Choose the Right BK-A Silicone for Your Mould

One professional two-part silicone range, available in Shore A5 and Shore A15 with 1 kg, 8 kg and 40 kg kit options.

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  • 1:1Mix ratio by weight
  • 30±5 minWorking time at 23°C
  • 4±1 hCure time at 23°C
Clear platinum-cure silicone being prepared for a controlled mould pour
BK-A Series supports professional mould making with grade and pack-size options reviewed for each application.

CHOOSE YOUR GRADE

Soft flexibility or stronger support

Both grades use the same 1:1 mix ratio by weight. Select the hardness that fits the mould geometry and demoulding requirement.

BK-A05Shore A5

Extra soft and highly flexible

Higher elongation and a softer cured rubber for flexible moulds, deep undercuts and complex demoulding.

Tear strength
10 N/mm
Tensile strength
2.5 MPa
Elongation
680%
BK-A15Shore A15

More support and tear strength

A firmer cured rubber with higher tear strength for general moulds, larger moulds and applications requiring more structural support.

Tear strength
15 N/mm
Tensile strength
2.0 MPa
Elongation
500%

AVAILABLE PACK SIZES

Three kits, each with equal Parts A and B

1 kg Kit0.5 kg Part A + 0.5 kg Part B
8 kg Kit4 kg Part A + 4 kg Part B
40 kg Kit20 kg Part A + 20 kg Part B
Mix ratio1:1 by weight
Working time30±5 min
Cure time4±1 h at 23°C
Shelf life12 months
Storage15–25°C, unopened

MOULD-MAKING APPLICATIONS

Designed for detailed casting workflows

  • Wax casting
  • Resin casting
  • Gypsum and plaster
  • Concrete casting
  • Architectural details
  • Rapid prototyping

Compatibility depends on the substrate, additives and process. Always run a small test cure before production.

AVAILABLE BK-A CONFIGURATIONS

Review the six standard grade and pack-size combinations

Current availability, pricing, shipping and suitability are confirmed before order.

  • 1 kg KitShore A5
  • 1 kg KitShore A15
  • 8 kg KitShore A5
  • 8 kg KitShore A15
  • 40 kg KitShore A5
  • 40 kg KitShore A15
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CUSTOM COLOUR

Custom Pigment Paste

Review the custom-colour workflow and colour-matching service for your selected silicone and application.

Explore Custom Silicone Colours →

FAQ

BK-A Series questions

How do I choose between BK-A05 and BK-A15?

Choose BK-A05 when you need a very soft, highly flexible mould for complex demoulding. Choose BK-A15 when the mould needs more support and higher tear strength. Test the selected grade in the intended process before production.

Must Parts A and B be mixed at 1:1?

Yes. Measure Part A and Part B accurately at 1:1 by weight, then mix thoroughly.

Can I vacuum degas the mixed silicone?

Yes. Vacuum degassing is recommended for deep cavities, fine detail or high surface-finish requirements. Allow enough container volume for the material to expand under vacuum.

What can inhibit platinum silicone curing?

Sulphur-containing clay, latex gloves, tin-cure silicone residue, amines, some epoxy curing agents and uncured or unsealed SLA/LCD/DLP resin prints can inhibit curing. Keep tools and surfaces clean and run a small test cure.

Can the silicone colour be customised?

Custom pigment paste and colour-matching support are available for review. Confirm compatibility and colour requirements before production.

What is included in the 1 kg, 8 kg and 40 kg kits?

The 1 kg kit contains 0.5 kg each of Parts A and B; the 8 kg kit contains 4 kg each; the 40 kg kit contains 20 kg each.

NEED HELP CHOOSING?

Tell us about the mould, casting material and required quantity.

We will review the application before confirming suitability, current availability, shipping or project-specific terms.

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