H-5800-0051-01-A

Data sheet: silicone rubber VTV 750

Data sheet: silicone rubber VTV 750

Description

Features

Suitable for

Cured properties

Colour

Transparency

Catalyst

Shore hardness

Tensile strength

Elongation at break

Tear strength

Coefficient of expansion

Processing information

Viscosity (at 25 °C)

Specific gravity (at 25 °C)

Mix ratio A:B (by weight)

Curing time

At 23 °C

At 60 °C

At 80 °C

CAT 740 /

750

-

40 A

-

6.5 N/mm 2

350 %

17 N/mm 2

2.7 × 10 -4 mm/mm/K

Medium viscosity, platinum catalysed, RTV-2

Chemical and heat resistant

Vacuum casting / wax casting, pottery cases

High tear strength, rigid

Colourless

Translucent

CAT VM20 CAT VM30

-

-

-

20 A

-

30 A

-

-

CAT VM2* Test / ISO standard where applicable

868

-

-

40 A

R 527

900 %

-

2.7 × 10 -4 mm/mm/K

520 %

-

2.7 × 10 -4 mm/mm/K

-

-

2.7 × 10 -4 mm/mm/K

R 527

34

BS 847

Part A

Part B

Part A

Part B

At 25 °C

At 40 °C

At 60 °C

90000 cPs

-

1.09

1.00

100:10

24 hr

8 hr to 12 hr

3 hr to 6 hr

120 min

0.1 %

90000 cPs

-

1.09

1.00

100:10

-

30 hr to 36 hr

10 hr

100 min

0.1 %

90000 cPs

-

1.09

1.00

100:10

3 days

15 hr to 20 hr

5 hr to 6 h

100 min

0.1 %

90000 cPs

-

1.09

1.00

See below*

See below*

See below*

0.1 %

Pot life (100 g at 25 °C)

Typical shrinkage

1

2

3

4

CAT VM1 (accelerator)

Curing time and pot life can be halved by adding 1 % VM1 to normal catalyst CAT 750. Add VM1 just before mixing.

*CAT VM2 (long pot life)

Mix ratio A:B:C (by weight) Pot life (100 g) Curing time

Mix VTV 750 CAT 750 CAT VM2 At 25 °C At 40 °C At 60 °C At 25 °C At 40 °C At 60 °C

100

100

100

100

10

7

3

0

0

3

7

10

120 min

180 min

280 min

480 min

26 min

40 min

60 min

90 min

15 min

20 min

25 min

35 min

24 hr

36 hr

48 hr

96 hr

10 hr to 12 hr 3 hr to 6 hr

20 hr to 25 hr 10 hr to 12 hr

35 hr to 40 hr 15 hr to 20 hr

50 hr to 60 hr 25 hr to 30 hr

The information in this data sheet is provided for general guidance only and must not be relied upon as a definitive statement of the product’s properties or suitability. Renishaw will not be liable for the consequences of any decision by you to use the product and you must conduct your own testing to determine whether or not the product is suitable for your needs.

Renishaw plc

Whitebridge Way

Whitebridge Park, Stone

Staffordshire ST15 8LQ

United Kingdom

T +44 (0) 1785 815651

F +44 (0) 1785 812115

E [email protected] www.renishaw.com/additive

Handling procedure

Mixing procedure

• Weigh the silicone and catalyst to the ratio indicated overleaf.

• Combine the two components and blend well, scraping the sides and bottom of the container to ensure that there are no unmixed pockets of material.

• Start the vacuum process to extract all excess air out of the mixed silicone. This usually takes around 10 min to 15 min.

• Ensure that enough volume remains in the container to accommodate the action of the material as the air is extracted from the mix. Silicone rubber may expand up to 7 times its original volume in the process of air extraction under vacuum.

• Pour the mixed material into the mould frame in a slow steady stream and allow to flow freely around and over the model.

Special notes

• It is recommended to use a Renishaw vacuum mixer for this work.

• It is important that a clean dry container and mixing paddle is used to avoid adding dirt or contaminants to the mix.

• If a Renishaw vacuum mixer is not available then the mixed material should be left in the container and placed into a Renishaw vacuum casting machine.

• Cure of the mixed silicone material may be inhibited by amines or products with a high sulfur content such as latex rubber.

• Patch testing is advisable prior to use to avoid inhibition.

Product information

Secondary degassing is recommended once pouring of the mould is completed. This is to eliminate voids around or under the model if air has been trapped while pouring. It is important to ensure that the whole degassing process is carried out well within the working time of the mixed silicone.

Please follow the correct procedure for use of your vacuum casting system, as set out in its operating instructions.

Always follow the instructions in the Product

Safety Data Sheets and always work in accordance with the safety instructions of the materials manufacturer. Safety Data Sheets can be found at www.renishaw.com.

Wear suitable respiratory protection, safety gloves and safety goggles during the entire filling procedure in accordance with the

Product Safety Data Sheets.

©2012 Renishaw plc. All rights reserved.

Renishaw reserves the right to change specifications without notice

RENISHAW® and the probe emblem used in the RENISHAW logo are registered trademarks of Renishaw plc in the UK and other countries.

apply innovation is a trademark of Renishaw plc.

H-5800-0051-01-A

Issued 1112 Part no. H-5800-0051-01-A